2024-03-30T02:19:26Zhttps://repositori.udl.cat/server/oai/requestoai:repositori.udl.cat:10459.1/478292021-08-30T15:04:29Zcom_10459.1_238com_10459.1_2col_10459.1_309col_10459.1_49291
Oró Prim, Eduard
Barreneche Güerisoli, Camila
Farid, Mohammed M.
Cabeza, Luisa F.
2015-02-03T10:47:42Z
2013
https://doi.org/10.1016/j.renene.2013.01.043
019203
0960-1481
http://hdl.handle.net/10459.1/47829
Storage and transport of temperature sensitive products have become an important issue worldwide. The
enhancement of thermal performance of cold application is under investigation and implementing
thermal energy storage (TES) systems by using phase change materials (PCM) is one of the solutions to
better storage. Hence, the selection of the suitable PCM for each specific application is an important
matter. In this paper, a TES system using PCM for low temperature applications such as commercial
freezers is studied. A set of PCM formulations based on ammonium chloride e water binary system were
tested and analyzed to provide information useful for the selection of PCM with regards to their melting
range, latent heat, stability under cycling, and cost. Thermal cycling was conducted to determine the
thermal reliability of the PCM and the thermal properties were determined using differential scanning
calorimetry (DSC) analysis.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2013
Cold storage
Low temperature
Phase change materials
Experimental study on the selection of phase change materials for low temperature applications
article
oai:repositori.udl.cat:10459.1/577632017-06-01T12:18:41Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_44504oai:repositori.udl.cat:10459.1/478602021-08-30T14:56:39Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Oró Prim, Eduard
Gil, Antoni
Gracia Cuesta, Alvaro de
Boer, Dieter
Cabeza, Luisa F.
2015-02-04T11:14:54Z
2012
https://doi.org/10.1016/j.renene.2012.01.008
017533
0960-1481
http://hdl.handle.net/10459.1/47860
The present work compares the environmental impact of three different thermal energy storage (TES)
systems for solar power plants. A Life Cycle Assessment (LCA) for these systems is developed: sensible
heat storage both in solid (high temperature concrete) and liquid (molten salts) thermal storage media,
and latent heat storage which uses phase change material (PCM). The aim of this paper is to analyze if the
energy savings related to the stored energy of the different systems are enough to balance the environmental
impact produced during the manufacturing and operation phase of each storage system. Some
hypothetical scenarios are studied using LCA methodology to point out the differences between each TES
system.
The system based on solid media, due to his simplicity, shows the lowest environmental impact per
kWh stored of all three systems compared. In addition, the liquid media (molten salts) shows the highest
impact per kWh stored because it needs more material and complex equipment.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2012
LCA
PCM
Thermal energy storage
Comparative life cycle assessment of thermal energy storage systems for solar power plants
article
oai:repositori.udl.cat:10459.1/584002018-09-05T10:15:34Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291col_10459.1_44504
Gasia, Jaume
Miró, Laia
Cabeza, Luisa F.
2016-11-07T09:55:10Z
2018-07-01T22:23:05Z
2016
https://doi.org/10.1016/j.rser.2016.03.019
024078
1364-0321
http://hdl.handle.net/10459.1/58400
This review is focused on the study of the requirement of high thermal conductivity of thermal energy storage (TES) materials and the techniques used to enhance it as this is one of the main obstacles to achieve full deployment of TES systems. Numerical and experimental studies involving different thermal conductivity enhancement techniques at high temperature (>150 °C) are reviewed and classified. This article complements Part 1, which reviews the different requirements that TES materials and systems should consider for being used for high temperature purposes and the approaches to satisfy them. The enhancements identified for this temperature range are the addition of extended surfaces like fins or heat pipes and the combination of highly conductive materials with TES material like graphite or metal foam composites and nanomaterials. Moreover the techniques presented are classified and discussed taking into account their research evolution in terms of maturity and publications.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd, (c) Elsevier, 2016
Thermal energy storage
High temperature
Thermal enhancement techniques
Thermal conductivity
Materials and system requirements of high temperature thermal energy storage systems: A review. Part 2: thermal conductivity enhancement techniques
article
oai:repositori.udl.cat:10459.1/4652972024-03-21T09:33:46Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Prieto, Cristina
Tagle-Salazar, Pablo D.
Patiño-Rodríguez, David
Schallenberg-Rodriguez, Julieta
Lyons, Padraig
Cabeza, Luisa F.
2024-03-12T08:13:55Z
2024-03-12T08:13:55Z
2024
https://doi.org/10.1016/j.est.2024.111203
034077
2352-152X
https://repositori.udl.cat/handle/10459.1/465297
Energy storage is acknowledged a key technology to meet the challenges posed by the energy transition. Shortterm grid-connected storage, based on Li-Ion batteries, is becoming commonplace but seasonal energy storage at grid-scale will be needed for deep decarbonisation of the electrical power system. Pumped hydropower is considered to be the only mature technology for such applications, but this paper demonstrates that two-tanks molten salts systems, that are used today in commercial concentrating solar power (CSP) plants, can also be considered a mature technology that can be used at large scale for seasonal energy storage. This was established by evaluating the annual heat losses of molten salts tanks using validated models of these systems. The results show that the heat losses in a very well insulated molten salts tanks are around 1 K/day, which would result in good economic performance of the power block even if storage was required for up to months.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Cristina Prieto et al, 2024
Seasonal energy storage
Two-tanks molten salts system
Performance
Heat losses
Use of molten salts tanks for seasonal thermal energy storage for high penetration of renewable energies in the grid
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/649922022-10-14T20:04:31Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Navarro Farré, Lidia
Solé, Aran
Martín, Marc
Barreneche Güerisoli, Camila
Olivieri, Lorenzo
Tenorio, José Antonio
Cabeza, Luisa F.
2018-10-29T07:21:49Z
2020-10-23T22:23:06Z
2018
https://doi.org/10.1016/j.enbuild.2018.10.005
027533
0378-7788
http://hdl.handle.net/10459.1/64992
Nowadays, there is an increasing interest in more efficient building materials and new technologies to accomplish the objectives defined by energy policies. The combination of energy efficient building designs and integration of renewable energies makes the use of thermal energy storage (TES) necessary. Within this context, the improvement of building envelopes by the use of phase change materials (PCM) has been widely studied. The PCM selection should fulfil the requirements of the specific application. In this study, a benchmarking of PCM available in the market was performed to undertake a material selection for a specific building application. The incorporation of PCM into a radiant wall technology present several requirements with especial interest on long-term thermal stability. A complete laboratory-scale characterization has been carried out considering the following properties: temperature of phase change, specific heat capacity, thermal conductivity, and stability.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd (c) Elsevier, 2018
Thermal energy storage (TES)
Phase change materials (PCM)
Buildings
Material selection
Benchmarking
Benchmarking of useful phase change materials for a building application
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/572462021-08-30T14:56:38Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291col_10459.1_44504
Serrano, Susana
Barreneche Güerisoli, Camila
Fernández Renna, Ana Inés
Farid, Mohammed M.
Cabeza, Luisa F.
2016-06-21T08:45:41Z
2015
https://doi.org/10.1016/j.enbuild.2014.10.015
021644
0378-7788
http://hdl.handle.net/10459.1/57246
Gypsum board containing a shape-stabilized PCM either as a sheet or as pellets is thermo-physically
characterized. The main objective is to elucidate which is the most efficient way to introduce the PCM
into gypsum boards by measuring the thermal transmittance, effective thermal conductivity, total heat
accumulated, and the average heat capacity. At their light it can be concluded that a gypsum board
containing 25% PCM is more thermally insulating than the gypsum without PCM, and the average heat
capacity of the samples containing sheet-PCM and pellets-PCM are higher than the gypsum by itself due
to the latent heat effect, being 41% and 33% respectively.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2015
Phase change materials (PCM)
Thermal energy storage (TES)
Fatty-ester
Gypsum
Composite gypsum containing fatty-ester PCM to be used as constructive system: Thermophysical characterization of two shape-stabilized formulations
article
oai:repositori.udl.cat:10459.1/843802024-03-20T14:54:26Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Boquera, Laura
Castro Chicot, José Ramón
Pisello, Anna Laura
Fabiani, Claudia
D'Alessandro, Antonella
Ubertini, Filippo
Cabeza, Luisa F.
2022-11-28T07:48:03Z
2022-11-28T07:48:03Z
2022-11-09
https://doi.org/10.1016/j.est.2022.106039
032787
2352-152X
http://hdl.handle.net/10459.1/84380
Future perspectives to improve the energy efficiency of concentrating solar power (CSP) plants are focused on increasing temperatures above 600 ◦C. Among the different components of a CSP plant, the thermal energy storage (TES) medium must withstand high operating temperatures. Concrete was identified as an exciting candidate for its mechanical and thermal properties, needing further experimental research about this specific application. A fundamental concrete element is the cement binder, bringing cohesion to the composite components. As a requisite, the cement needs to be heat-resistant, and calcium aluminate cement (CAC) suits this demand. This cement is characterised by curing temperature-driven crystallisation changes, triggering an alteration of material properties. Considering that at 60 ◦C, the metastable hexagonal crystallisation is converted into a stable cubic crystallisation, seven curing cases were proposed in this study. After the curing process, thermo-mechanical properties of calcium aluminate cement paste were tested before and after thermal cycles from 290 ◦C to 650 ◦C. The results showed that, despite thermal cycling, the immediate hydration at 60 ◦C results in a higher thermal conductivity and compressive strength than standard curing at 20 ◦C.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Laura Boquera et al., 2022
Cement paste
Calcium aluminate cement conversion
Curing procedure
Curing temperature
High temperature
Thermal energy storage
Effect of the curing process on the thermomechanical properties of calcium aluminate cement paste under thermal cycling at high temperatures for thermal energy storage applications
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/713152022-10-20T17:03:36Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Abokersh, Mohamed Hany
Norouzi, Masoud
Boer, Dieter
Cabeza, Luisa F.
Gasa, Gemma
Prieto, Cristina
Jiménez, Laureano
Vallès Rasquera, J. Manel
2021-05-26T09:02:04Z
2021
https://doi.org/10.1016/j.renene.2021.04.136
031326
0960-1481
http://hdl.handle.net/10459.1/71315
The circular economy can be promoted as a solution to support the sustainability market position of renewable energy systems. To design a circular and sustainable system, a structured approach is needed. The present study develops a methodology framework for sustainable circular system design (SCSD), aiming to assess thermal energy storage (TES) technologies from a sustainable perspective. To this end, a composite indicator, namely, environmental sustainability and circularity indicator (ESC) is provided. This indicator combines the environmental impacts of the TES system via the conduction of a life cycle assessment and its circulatory performance using the product-level material circularity indicator (MCI). The developed methodology is applied to a case study of high-temperature TES using molten salts as a part of a concentrated solar power plant. The SCSD embraces the analysis for the most relevant processes through proposing different ecological scenarios including, increasing the recycling rates (Modest Scenario), increasing the reuse rates (Medium Scenario), and a combination of both (Optimistic scenario). The circularity analysis showed that for the Modest, Medium and optimistic scenarios, the MCI moves from 20.6% for the current situation to 30.3%, 38.6%, and 46.4%, respectively. Accordingly, the optimistic scenario showed the most environmentally sustainable and circular scenario with ESC of 7.89%, whereas the Modest and Medium scenarios exhibited ESCs of 1.20% and 2.16%, respectively. A major obstacle for substantial improvement of the circulatory and ESC is the high share of unrecyclable molten salts in the system and therefore, any effort to improve the circulatory and the environmental benefits of this system can be reached by using more environmentally friendly alternative materials. The study concludes that the integration of reusing and recycling at the initial design should be sought in order to achieve a more environmentally sustainable and circular outcome.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd (c) M. Abokersh et al, 2021
Life cycle assessment (LCA)
Circular economy
Material circularity index
Thermal energy storage (TES)
Concentrated solar power
Sustainability
A framework for sustainable evaluation of thermal energy storage in circular economy
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/661812019-04-12T00:06:54Zcom_10459.1_243com_10459.1_2com_10459.1_238col_10459.1_3332col_10459.1_309
Bradineras, F. Javier
Castro Chicot, José Ramón
Iglesias Rodríguez, José María
Martorell, Ingrid
Nogués Aymamí, Miquel
Roca Enrich, Joan
2019-04-11T08:06:25Z
2019-04-11T08:06:25Z
2012
2385-6203
http://hdl.handle.net/10459.1/66181
Actualmente, para abordar el cálculo estructural en la Universitat de Lleida existe
software de uso profesional. Los dos grandes inconvenientes para aplicarlo como herramienta de
docencia son, su alto coste económico y el hecho de que no facilita el aprendizaje del alumnado,
puesto que únicamente permite obtener los resultados finales del cálculo, sin posibilidad de
estudiar cuáles han sido los pasos realizados ni los valores de cálculo intermedios.
La Universitat de Lleida, ha promovido la elaboración de un software de cálculo
estructural aplicando el método matricial de la rigidez, para que el estudiante, de forma
autodidacta, sea capaz de generar sus propios ejemplos y validar, tanto las soluciones finales
como los resultados intermedios. De esta forma el estudiante podrá conocer los puntos críticos
donde los errores son más habituales y será capaz de resolverlos de forma autónoma.
Nowadays, professional software exist to allow structural calculation learning in the
University of Lleida. There are two main drawbacks for its application as a teaching tool: its high
cost and the inability for showing intermediate values of calculation; therefore, students are not
able to check intermediate steps. The University of Lleida has promoted the development of an structural analysis software
applying the matrix stiffness method. The target is to achieve students being able to generate
their own examples and validate both, the final solutions and the intermediate results, in a selflearning
way. That procedure allows to find out the critical items where errors are commonly
made, in order that students are able to fix them by themselves.
spa
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Martorell, et al., 2012
Autoaprendizaje
Cálculo matricial
Estructuras
Software para la mejora del aprendizaje del cálculo estructural en ingeniería y arquitectura.Programa Barras V-2.0, Universitat de Lleida
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/478832022-10-17T19:07:06Zcom_10459.1_238com_10459.1_2col_10459.1_309col_10459.1_49291
Gil, Antoni
Oró Prim, Eduard
Miró, Laia
Peiró Bell-lloch, Gerard
Ruiz-Pardo, Álvaro
Salmerón, José Manuel
Cabeza, Luisa F.
2015-02-09T08:03:19Z
2014
https://doi.org/10.1016/j.ijrefrig.2013.05.013
019651
0140-7007
http://hdl.handle.net/10459.1/47883
This present paper is focused on the study of high temperature thermal energy storage
(TES) using phase change materials (PCM) to be applied on cooling and refrigeration systems
by solar cooling. Thus, a pilot plant with a working temperature range between 150
and 200 C was designed and built at the University of Lleida (Spain). Hydroquinone was
selected for the specific application from different PCM candidates as the most suitable
material after a literature review and a differential scanning calorimetry (DSC) analysis.
This PCM has a phase change temperature range between 166 C and 173 C and a melting
enthalpy of 225 kJ kg 1. Two storage configurations were evaluated using the same PCM to
have preliminary results before the final storage tank design. From the pilot plant results
and experience, a 5 Tn PCM storage tank was designed and built to work in a real solar
cooling installation in Seville (Spain).
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2013
Solar energy
Cooling
Thermal storage
Experimental analysis of hydroquinone used as phase change material (PCM) to be applied in solar cooling refrigeration
article
oai:repositori.udl.cat:10459.1/589202019-04-29T13:55:33Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Zsembinszki, Gabriel
Gracia Cuesta, Alvaro de
Moreno Argilés, Pere
Rovira, Ricard
González, Miguel Ángel
Cabeza, Luisa F.
2017-01-10T08:29:06Z
2019-03-25T23:24:24Z
2017
https://doi.org/10.1016/j.applthermaleng.2016.12.059
025110
1359-4311
http://hdl.handle.net/10459.1/58920
The extended use of cooling and refrigeration systems in industrial, building and transport sectors may have a negative impact on the climate change and ozone depletion. Thus, important aspects related to these systems, such as refrigerant charge level, malfunction, or refrigerant leakage, must be taken into account. In this sense, the study of refrigeration system performance under different conditions can be very useful. In this paper, a novel methodology for modelling a simple compression refrigeration system is described. Starting from three input parameters, i.e. the ambient air temperature, the cold room air temperature, and the degree of superheating, a calculation algorithm based on iterative loops is used in the model to determine the operating point of the system. An experimental set-up consisting of a walk-in freezer unit was used for the development and validation of the model. The model is system dependent, i.e. empirical correlations must be derived for determining some of the features of system components. The numerical results are in good agreement with the experiment, therefore the model can be a reliable tool for the detection of a system malfunction.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd, (c) Elsevier, 2017
Numerical simulation
Compression refrigeration system
Experimental validation
A novel numerical methodology for modelling simple vapour compression refrigeration system
article
oai:repositori.udl.cat:10459.1/477622021-08-30T15:04:35Zcom_10459.1_238com_10459.1_2col_10459.1_309
Martorell, Ingrid
Medrano Martorell, Marc
Solé Cutrona, Cristian
Vila Rubio, María Nieves
Cabeza, Luisa F.
2015-01-28T09:46:26Z
2009
https://doi.org/10.1080/03601270802708434
022365
0360-1277
http://hdl.handle.net/10459.1/47762
With the increasing number of older people in the world and their interest
in education, universities play an important role in providing effective
learning methodologies. This paper presents a new instructional
methodology implementing inquiry-based learning (IBL) in two courses
focused on alternative energies in the Program for Older People at the
University of Lleida (UdL) in Spain. The instructional methodology is
evaluated and results are discussed after two years of studies. The
instructional methodology presented in this paper helped students to build and reinforce scientific skills and knowledge construction. This
work may have potential relevance to other instructors involved in adult
education.
eng
info:eu-repo/semantics/restrictedAccess
(c) Taylor & Francis, 2009
Inquiry-Based Learning for Older People at a University in Spain
article
oai:repositori.udl.cat:10459.1/648782018-10-17T00:23:32Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_44504
Weber, Gundula
Cabeza, Luisa F.
Zsembinszki, Gabriel
Chiu, Justin
2018-10-16T07:48:37Z
2018-10-16T07:48:37Z
2017
https://doi.org/10.18178/ijlt.3.3.189-193
027018
2377-2891
2377-2905
http://hdl.handle.net/10459.1/64878
Innovative Pathways to Thermal Energy Storage (INPATH- TES) is to create a network of academia, research institutes and small and medium enterprises that are cooperating in defining an innovative programme and in its deployment to implement a unique joint PhD programme on Thermal Energy Storage (TES) technologies. For the development of the PhD program the presence of a wide range of stakeholders ensures the inclusion of knowledge, experiences and needs. The PhD uses the possibility of competence & skills driven learning outcomes to educate future students. Through the carefully designed Intended Learning Outcomes (ILOs) and Achieved Learning Outcomes (ALOs), following the EIT pedagogical methodology, learners will receive knowledge up to the necessary specific level. The future role of teachers will change and will include the design of overarching ILOs, the assembling of knowledge material and ALOs and moderate peer discussions. Main challenges were identified through the approval of the joint PhD programme by each of the participating countries due to the structure, doctoral training and the access to a PhD programme. Nevertheless the final result of such a network will lead to a qualification of professionals in these technologies for European Research and Industrial Institutions.
eng
info:eu-repo/semantics/openAccess
(c) International Journal of Learning and Teaching, 2017
Pathways to a European PhD for Thermal Energy Storage
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/588192022-10-06T16:43:18Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291col_10459.1_44504
Pérez Luque, Gabriel
Coma Arpón, Julià
Sol i Felip, Salvador
Cabeza, Luisa F.
2016-12-15T09:37:17Z
2019-02-01T23:27:53Z
2017
https://doi.org/10.1016/j.apenergy.2016.11.055
025086
0306-2619
http://hdl.handle.net/10459.1/58819
To “green” building envelopes is currently one of the most promising ways to provide energy savings in buildings and to contribute to the urban heat island effect mitigation. The shadow effect supplied by plants is the most significant parameter for this purpose. One way to characterize the potential shadow effect of greenery is to calculate the facade foliar density by means of the leaf area index (LAI). As LAI is commonly used in horizontal crops, their use in vertical greenery systems (VGS) has generated dispersion and uncertainty in previous studies both in terms of methodologies and results obtained. In addition, a lack of data relating to the influence of the facade orientation in the final contribution of vertical greenery to the energy savings has been observed in previous studies.
This study aims at establishing a common and easy way to measure LAI and to lick it to the energy savings provided by VGS. Moreover, the energy savings achieved as well as the influence of facade orientation on the final thermal behaviour of two different VGS, a double-skin green facade and a green wall, was studied.
From the results, it can be stated that the most simple and quick procedure to measure LAI in order to characterize the foliar density of VGS is the indirect method based on the amount of light transmitted through the green screen. From the experimental tests interesting energy savings were obtained (up to 34% for Boston Ivy pant specie with a LAI of 3.5–4, during summer period under Mediterranean continental climate). Moreover, the dependence on facade orientation was confirmed with representative contribution over the whole energy savings from East and West orientation.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd, (c) Elsevier, 2017
Vertical greenery systems (VGS)
Green facades
Energy savings
Buildings
Leaf area index (LAI)
Shadow effect
Green facade for energy savings in buildings: The influence of leaf area index and facade orientation on the shadow effect
article
oai:repositori.udl.cat:10459.1/583822019-02-01T10:05:45Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Ruiz-Cabañas, F. Javier
Jové, Aleix
Prieto, Cristina
Madina, Virginia
Fernández Renna, Ana Inés
Cabeza, Luisa F.
2016-11-04T09:52:57Z
2019-01-31T23:21:47Z
2017
https://doi.org/10.1016/j.solmat.2016.10.010
024830
0927-0248
http://hdl.handle.net/10459.1/58382
Phase change materials (PCM) is one of the most interesting solutions to be used in thermal energy storage (TES) systems for direct steam generation (DSG) thermosolar facilities. Properties such as high energy density and energy storing/delivery at constant temperature bring PCM based systems in excellent candidates for DSG facility storage units. Accordingly, LiOH-KOH peritectic mixture, with a melting point of 315 °C and an enthalpy change of 535 kJ/kg, has been reported as attractive solution for the saturated storage module in DSG plants. A steam-PCM heat exchanger is the critical component to carry out the thermal transference between both substances. Although materials selection to be applied for steam applications is well known, lack of knowledge is detected in the field of high temperature hydroxides corrosion. Therefore, three metallic materials, A516 Gr70 carbon steel, A316L stainless steel and Inconel 625 Ni-base alloy, have been evaluated to determine their corrosion performance after hydroxides exposure. While A516 Gr70 was discarded for this application due to high corrosion rates, A316L and Inconel 625 displayed good corrosion resistance after 2640 h. Finally, A316L stainless steel was selected as potential candidate for the construction of the steam-PCM heat exchanger considering cost and thermal efficiency optimization.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd, (c) Elsevier B.V., 2016
Corrosion
Solar energy
Direct steam generation (DSG)
Thermal energy storage (TES)
Phase change material (PCM)
Hydroxides
Materials selection of steam-phase change material (PCM) heat exchanger for thermal energy storage systems in direct steam generation facilities
article
oai:repositori.udl.cat:10459.1/478212017-03-10T13:02:04Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Pérez Luque, Gabriel
Coma Arpón, Julià
Solé Cutrona, Cristian
Castell, Albert
Cabeza, Luisa F.
2015-02-03T09:45:04Z
2012
https://doi.org/10.1016/j.egypro.2012.11.054
018905
1876-6102
http://hdl.handle.net/10459.1/47821
This study is another step of a long-term work in order to study the thermal behaviour of extensive green roofs in dry
Mediterranean Continental climate. In this paper there are two main goals. On one hand, the possibility of using
rubber crumbs as a drainage layer in green roofs, substituting the porous stone materials used in some commercial
solutions is studied. On the other hand, new data concerning the use of green roofs as passive system for energy
savings in dry Mediterranean Continental climate is provided. First results correspond to summer 2011, when the roof
was just planted and the irrigation system installed. The vegetation cover in those days was about 20% of the roof
surface. With an internal set-point of 24 °C first results show an improvement in energy consumption with respect to
the reference cubicle. New data will be recorded during 2012 when the vegetation has developed and it is expected
better results than in 2011.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/3.0/es/
cc-by-nc-nd (c) Gabriel Pérez Luque et al., 2012
Green roof
drainage lyer
rubber crumbs
Green roofs as passive system for energy savings when using rubber crumbs as drainage layer
article
oai:repositori.udl.cat:10459.1/842802022-11-22T00:06:39Zcom_10459.1_238com_10459.1_2col_10459.1_309col_10459.1_49291
Martorell, Ingrid
Camarasa, Jaume
Vilà Miró, Roger
Solé Cutrona, Cristian
Castell, Albert
2022-11-21T09:56:08Z
2022-11-21T09:56:08Z
2022-11-08
https://doi.org/10.3390/en15228340
032812
1996-1073
http://hdl.handle.net/10459.1/84280
Polyethylene has widely been used in radiative cooling applications because of high transmittance values in the atmospheric window. However, it presents optical and mechanical degradation when exposed to environmental conditions and must be replaced every few months. This paper aims to find an alternative to polyethylene to be used in a unique device, the Radiative Collector and Emitter (RCE), that combines solar collection and night-time radiative cooling. The aging evolution analysis of five cheap and market available plastic films (two low density polyethylene, one high density polyethylene, one polypropylene, and one fluorinated ethylene propylene) exposed to environmental conditions was performed. FT-IR spectra and mechanical traction tests were performed before and after 90 days of exposure to the environment. Results confirm that polyethylene undergoes a degradation process both when it is covered by a glass and when it is uncovered. However, it maintains high average transmittance values in the atmospheric window. Polypropylene has average transmittance values slightly lower than polyethylene, but its aging behaviour is better since no oxidative processes are detected when the material is covered with glass. For all this, PP-35 is an interesting candidate for night-time radiative cooling wind-shields.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Martorell, Ingrid et al., 2022
Night-time radiative cooling
Wind-shield
Plastic films
Transmittance
Mechanical tests
Aging
Aging study of plastics to be used as Radiative cooling wind-shields for night-time radiative cooling - Polypropylene as an alternative to polyethylene.
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/478312021-08-30T14:56:39Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941
Gil, Antoni
Oró Prim, Eduard
Castell, Albert
Cabeza, Luisa F.
2015-02-03T11:06:07Z
2013
https://doi.org/10.1016/j.applthermaleng.2013.02.016
019254
1359-4311
http://hdl.handle.net/10459.1/47831
Thermal energy storage (TES) systems are growing to a relevant role in solar cooling applications. Hence,
high energy density is a desirable property of the TES system. Phase change materials (PCM) helps to
increase this characteristic. A high temperature pilot plant able to test different types of TES systems and
materials was designed and built at the University of Lleida (Spain). This pilot plant is composed mainly
of three parts: heating system, cooling system, and different storage tanks. Two identical storage tanks
based on the shell-and-tubes heat exchanger, one of them including 196 squared fins in the bundle of the
tubes and the other without, were experimentally tested. Hydroquinone was selected as the storage
material, having a latent heat of 205 kJ/kg and a phase change temperature between 168 and 173 C. The
aim of this paper is to test experimentally, and compare the average effectiveness of the TES systems
analyzed using PCM for solar cooling and refrigeration applications. It was found out that for the same
tank configurations (shell-and-tubes) even changing drastically the dimensions of the tank or the
number and the diameter of the tubes, the average effectiveness curve proposed in the literature fits well
with the results showed here.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2013
TES systems
Phase change materials
High temperature
Experimental analysis of the effectiveness of a high temperature thermal storage tank for solar cooling applications
article
oai:repositori.udl.cat:10459.1/695742023-02-02T14:03:09Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Prabhakar, Mohit
Saffari Tabalvandani, Mohammad
Gracia Cuesta, Alvaro de
Cabeza, Luisa F.
2020-09-30T10:40:15Z
2022-09-17T22:09:10Z
2020
https://doi.org/10.1016/j.enbuild.2020.110483
030481
0378-7788
http://hdl.handle.net/10459.1/69574
In recent years, the building sector has been responsible for continuous increase in energy consumption in the world. Space heating and cooling accounts for 34% of this energy consumption in buildings. In this context, using thermal energy storage (TES) can reduce energy consumption for space air conditioning. The use of phase change materials (PCM) as latent heat thermal energy storage (LHTES) system in the building envelope has been of great interest for passive cooling applications due to the high energy storage capacity of this technology. However, in order to utilize the full potential of a PCM, it needs to be fully charged at each cycle. Ventilation during the night is an effective method which can be used in PCMenhanced office buildings with the aim of charging the PCM every required cycle. In the present study, PCM melting temperature of office building in various climate conditions was optimized using a simulation-based optimization and coupled with free cooling operation. Ventilation control strategies were used to improve the cooling energy performance of the PCM enhanced building integrated into envelopes. It was found that charging PCM with night ventilation, especially when using some specific control strategies of natural ventilation operated by external windows opening results in considerable cooling energy savings. The study was conducted for 15 different cities around the world. It was found that, in hot arid conditions, PCM passive cooling system was ineffective. Although, the energy savings were improved by coupling PCM and natural ventilation in these climate conditions. But the benefits were more or less similar to using natural ventilation only. On the other hand, in temperate condition, the effectiveness of PCM was increased from 3.32% to 25.62% by coupling a PCM passive system with night ventilation. It was further improved to 40% when using PCM with temperature-controlled ventilation. Moreover, it can be said that smart control of ventilation can lead to considerable energy savings.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd (c) Elsevier, 2020
PCM
Natural ventilation
Optimization
Passive cooling system
Improving the energy efficiency of passive PCM system using controlled natural ventilation
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/478172021-08-30T14:56:39Zcom_10459.1_238com_10459.1_2col_10459.1_309col_10459.1_49291
Oró Prim, Eduard
Chiu, Justin
Martin, Viktoria
Cabeza, Luisa F.
2015-02-03T08:42:28Z
2013
https://doi.org/10.1016/j.applthermaleng.2012.07.020
018054
1359-4311
http://hdl.handle.net/10459.1/47817
This paper presents, compares and validates two different mathematical models of packed bed storage
with PCM, more specifically the heat transfer during charge of the PCM. The first numerical model is
a continuous model based on the Brinkman equation and the second numerical model treats the PCM
capsules as individual particles (energy equation model). Using the Brinkman model the flow field inside
the porous media and the heat transfer mechanisms present in the packed bed systems can be described.
On the other hand, using the energy equation model the temperature gradient inside the PCM capsules
can be analysed. Both models are validated with experimental data generated by the authors. The
experimental set up consists mainly of a cylindrical storage tank with a capacity of 3.73 L full of
spherically encapsulated PCM. The PCM used has a storage capacity of 175 kJ/kg between 2e13 C. The
results from the energy equation model show a basic understanding of cold charging. Moreover, three
different Nu correlations found in the literature were analysed and compared. All of them showed the
same temperature profile of the PCM capsules; hence any of them could be used in future models. The
comparison between both mathematical models indicated that free convection is not as important as
forced convection in the studied case.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2012
Phase change material
Packed bed
Numerical simulation
Comparative study of different numerical models of packed bed thermal energy storage systems
article
oai:repositori.udl.cat:10459.1/477532023-01-27T19:56:16Zcom_10459.1_238com_10459.1_2col_10459.1_309col_10459.1_49291
Mazman, Muhsin
Cabeza, Luisa F.
Mehling, Harald
Nogués Aymamí, Miquel
Evliya, Hunay
Paksoy, Halime Ö.
2015-01-28T09:36:57Z
2009
https://doi.org/10.1016/j.renene.2008.10.016
013293
0960-1481
http://hdl.handle.net/10459.1/47753
Thermal energy storage systems which keep warm and cold water separated by means of gravitational
stratification have been found to be attractive in low and medium temperature thermal storage applications
due to their simplicity and low cost. This effect is known as thermal stratification, and has been
studied experimentally thoughtfully. This system stores sensible heat in water for short term applications.
Adding PCM (phase change material) modules at the top of the water tank would give the system
a higher storage density and compensate heat loss in the top layer because of the latent heat of PCM.
Tests were performed under real operating conditions in a complete solar heating system that was
constructed at the University of Lleida, Spain. In this work, new PCM-graphite compounds with optimized
thermal properties were used, such as 80:20 weight percent ratio mixtures of paraffin and stearic
acid (PS), paraffin and palmitic acid (PP), and stearic acid and myristic acid (SM). The solar domestic hot
water (SDHW) tank used in the experiments had a 150 L water capacity. Three modules with a cylindrical
geometry with an outer diameter of 0.176 m and a height of 0.315 m were used. In the cooling experiments,
the average tank water temperature dropped below the PCM melting temperature range in about
6–12 h. During reheating experiments, the PCM could increase the temperature of 14–36 L of water at the
upper part of the SDHW tank by 3–4 C. This effect took place in 10–15 min. It can be concluded that PS
gave the best results for thermal performance enhancement of the SDHW tank (74% efficiency).
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2008
Phase change material
Solar energy
Domestic hot water
Utilization of phase change materials in solar domestic hot water systems
article
oai:repositori.udl.cat:10459.1/478412021-08-30T15:04:30Zcom_10459.1_238com_10459.1_2col_10459.1_309col_10459.1_49291
Cabeza, Luisa F.
Barreneche Güerisoli, Camila
Miró, Laia
Morera Prat, Josep M.
Bartolí, Esther
Fernández Renna, Ana Inés
2015-02-03T11:58:38Z
2013
https://doi.org/10.1016/j.rser.2013.03.017
019272
1364-0321
http://hdl.handle.net/10459.1/47841
This paper presents a review of the literature on low carbon and low embodied energy materials in buildings. Embodied energy is defined and discussed vs. operating energy of buildings and its growing importance due to the implementation of the Energy Building Performance Directive (EBPD) in Europeas example. The difficulty of measuring embodied energy and the difficulty in comparing published data are highlighted, showing an example of proposed new methodology found in the literature. Relationship between embodied energy and embodied CO2 or CO2 footprint is defined. Different materials defined in
the literature as low carbon materials are referred, such as cement and concrete, wood, bricks, rammed earth and sandstone. The review shows the research efforts found in the literature to develop new materials with less embodied energy. Finally, the effect of material substitution in the embodied energy of a building is reviewed in the literature.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2013
Low energy materials
Low carbon materials
Embodied energy
Low carbon and low embodied energy materials in buildings: A review
article
oai:repositori.udl.cat:10459.1/477432021-08-30T15:04:35Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941
Zalba, Belén
Marín, José M.
Cabeza, Luisa F.
Mehling, Harald
2015-01-28T09:26:43Z
2003
https://doi.org/10.1016/S1359-4311(02)00192-8
001693
1359-4311
http://hdl.handle.net/10459.1/47743
Thermal energy storage in general, and phase change materials (PCMs) in particular, have been a main
topic in research for the last 20 years, but although the information is quantitatively enormous, it is also
spread widely in the literature, and difficult to find. In this work, a review has been carried out of the history
of thermal energy storage with solid–liquid phase change. Three aspects have been the focus of this review:
materials, heat transfer and applications. The paper contains listed over 150 materials used in research as
PCMs, and about 45 commercially available PCMs. The paper lists over 230 references.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier Science, 2003
phase change materials
latent thermal energy storage
Heat transfer
Review on thermal energy storage with phase change: materials, heat transfer analysis and applications
article
oai:repositori.udl.cat:10459.1/478372022-10-17T19:24:42Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Pérez Luque, Gabriel
Rincón, Lídia
González, J. M.
Cabeza, Luisa F.
2015-02-03T11:29:13Z
2011
https://doi.org/10.1016/j.enconman.2010.11.008
016140
0196-8904
http://hdl.handle.net/10459.1/47837
In order to obtain data on the behaviour of green facades in buildings as a passive system for energy savings
in dry Mediterranean Continental climate a long-term work has been performed. This paper presents
the first results of two actions developed during 2009. First, the growth of four different climbing plants
as well as their ability to provide shadow was studied. Second, monitoring for a year of a real green facade
was carried out. The results confirmed the great capacity of green facades to produce shade, reducing the
heat on the facade wall of the building. It was also verified that a microclimate between the wall of the
building and the green curtain are created, characterized by slightly lower temperatures and higher relative
humidity. This means that the green screen acts as a wind barrier and confirms the evapotranspiration
effect of the plants. On the other hand, these results did not allow withdrawing conclusions about
the insulation effect of green facades.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2010
Green facades
Passive energy system
Experimental work
Behaviour of green facades in Mediterranean Continental climate
article
oai:repositori.udl.cat:10459.1/711992021-04-30T00:20:40Zcom_10459.1_238com_10459.1_2col_10459.1_309
Navarro Diarte, Alejandra
Puig, Rita
Kiliç, Eylem
Penavayre, Sophie
Fullana i Palmer, Pere
2021-04-29T10:24:25Z
2021-04-29T10:24:25Z
2017-01
https://doi.org/10.1016/j.jclepro.2016.11.124
027757
0959-6526
http://hdl.handle.net/10459.1/71199
Environmental sustainability in the wine sector has become a priority, as a result of both the growing interest in environmental issues and the consumer's demand for more information regarding the environmental impact of the products they purchase. In this context, the use of carbon footprint as an indicator to assess and report the environmental burdens associated with wine production has gained a role of primary interest. The present study has the aim of improving the wine sector's sustainability by providing inventory data on wine production systems from a total of 18 wineries located in major wine-producing regions in Spain and the South of France. The main novelty of this paper is: the corporate carbon footprint approach, the greater number of wineries studied, the diversity of location of those wineries, the detail of data presented and the identification of the best reference flow for vineyards. Data was statistically analysed. Vineyard consumptions are usually related to the area of cultivation. However, although 1 ha of vineyard or 1 kg of harvested grape could both be considered good reference flows for vineyard processes, this study shows a greater standard deviation of average data calculated per ha rather than per kg. Impact results show a major contribution of the winery phase to the corporate carbon footprint (73%), mainly due to glass production for bottling (45.6% contribution) and electricity consumption (9.2%). In the vineyard phase, contribution comes mainly from diesel production and combustion due to field works (11.3%) and the use of phytosanitary products (6.0%). The results revealed that with the establishment of best practices and with optimized resource consumption, the corporate carbon footprint values can be reduced by almost 25%. The comparative results presented can be used as a reference that will enable wineries to compare their impacts to the average, to identify in which aspects they are within the average and which aspects they are outside the average and whether these aspects are significant to their carbon footprint. This may encourage wineries to adopt measures for Eco-innovation through carbon emission reduction.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd, (c) Elsevier, 2017
Corporate carbon footprint
Eco-innovation
Vineyard
Winery
Wine industry's environmental performance
Inventory data
Eco-innovation and benchmarking of carbon footprint data for vineyards and wineries in Spain and France
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/585192022-10-10T17:02:27Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291col_10459.1_44504
Jacob, Rhys
Belusko, Martin
Fernández Renna, Ana Inés
Cabeza, Luisa F.
Saman, Wasim
Bruno, Frank
2016-11-16T08:34:22Z
2018-10-15T22:26:49Z
2016
https://doi.org/10.1016/j.apenergy.2016.08.027
024725
0306-2619
http://hdl.handle.net/10459.1/58519
The intermittency of renewable energy systems remains one of the major hurdles preventing a large scale uptake of these technologies and concentrated solar power (CSP) systems are no different. However, CSP has the benefit of being able to store excess heat using thermal energy storage (TES). For the uptake of CSP with TES it must be demonstrated that the technology is both economically as well as environmentally feasible. This paper aims to investigate the economic and environmental impact of several TES options that are available for CSP systems. The investigated systems include an encapsulated phase change material (PCM) system, a coil-in-tank PCM system and a liquid sodium TES system. The economic impact in the current study refers to the capital cost (CAPEX) of each system including the tank, storage material, encapsulation cost (if applicable) and allowances for construction and engineering. The environmental impact of each system is accounted by calculating the embodied energy of each of the system components. Each storage system will be required to store a comparable amount of energy so that reliable conclusions can be drawn. The results from this analysis conclude that the encapsulated PCM (EPCM) and coil-in-tank system represent an embodied energy of roughly one third of the corresponding state-of-the-art two-tank molten salt system.
Furthermore, the EPCM and coil-in-tank systems result in CAPEX reductions of 50% and 25% over the current state-of-the-art two-tank molten salt system. The liquid sodium system was found to result in higher embodied energy and CAPEX than any previously studied TES system. Finally, the advantages and disadvantages of each system was discussed and compared to previous literature.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd, (c) Elsevier, 2016
Embodied energy
Environmental impact
High temperature thermal energy storage (TES) systems
Concentrated solar power (CSP) systems
Phase change materials (PCMs)
Embodied energy and cost of high temperature thermal energy storage systems for use with concentrated solar power plants
article
oai:repositori.udl.cat:10459.1/583842018-02-05T13:55:57Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_44504
Ushak, Svetlana
Gutiérrez, Andrea
Galazutdinova, Yana
Barreneche Güerisoli, Camila
Cabeza, Luisa F.
Grágeda, Mario
2016-11-04T10:13:01Z
2017-09-30T22:23:25Z
2016
https://doi.org/10.1002/er.3542
024295
0363-907X
http://hdl.handle.net/10459.1/58384
Brines coming from salted lakes such as that at the Atacama desert in Chile produce by-products or wastes which today are stored in the nearby from the production areas. Bischofite is one of those by-products, and therefore, its composition may vary from batch to batch. Because bischofite has been identified as a good candidate to be used as phase change material (PCM) for latent heat thermal energy storage, the influence of the variation of bischofite composite with its main impurities in this potential used needs to be evaluated. The main impurities of bischofite are the cations sodium, potassium and lithium and the anions chloride and sulfate. The results of this investigation established that the presence of KCl and NaCl in bischofite (up to 5 wt%) does not affect its use as PCM, because its melting enthalpy and temperature do not vary significantly. It is interesting that small contents of LiCl in bischofite do not change significantly its melting enthalpy but decrease the melting temperature. Such change may enable the usage of this material as PCM in other applications at lower temperatures.
eng
info:eu-repo/semantics/openAccess
(c) John Wiley & Sons, 2016
Thermal energy storage
Latent heat
Phase change material
Non-metallic industry
Valorization of by-product
Influence of alkaline chlorides on thermal energy storage properties of bischofite
article
oai:repositori.udl.cat:10459.1/683192020-03-25T00:20:38Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291col_10459.1_44504
Zsembinszki, Gabriel
Fernández, Ángel G.
Cabeza, Luisa F.
2020-03-24T10:34:26Z
2020-03-24T10:34:26Z
2020
https://doi.org/10.3390/app10062116
029893
2076-3417
http://hdl.handle.net/10459.1/68319
The implementation of thermal energy storage systems using phase change materials to support the integration of renewable energies is a key element that allows reducing the energy consumption in buildings by increasing self-consumption and system efficiency. The selection of the most suitable phase change material is an important part of the successful implementation of the thermal energy storage system. The aim of this paper is to present the methodology used to assess the suitability of potential phase change materials to be used in two innovative energy storage systems, one of them being mainly intended to provide cooling, while the other provides heating and domestic hot water to residential buildings. The selection methodology relies on a qualitative decision matrix, which uses some common features of phase change materials to assign an overall score to each material that should allow comparing the different options. Experimental characterization of the best candidates was also performed to help in making a final decision. The results indicate some of the most suitable candidates for both systems, with RT4 being the most promising commercial phase change material for the system designed to provide cooling, while for the system designed to provide heating and domestic hot water, the most promising candidate is RT64HC, another commercial product.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Gabriel Zsembinszki et al., 2020
Thermal energy storage (TES)
Phase change material (PCM)
Heating and cooling
Material selection
Selection methodology
Selection of the appropriate phase change material for two innovative compact energy storage systems in residential buildings
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/574402021-08-30T14:56:40Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941
Gebreslassie, Berhane Hagos
Medrano Martorell, Marc
Boer, Dieter
2016-07-12T08:45:31Z
2010
https://doi.org/10.1016/j.renene.2010.01.009
014709
0960-1481
http://hdl.handle.net/10459.1/57440
An exergy analysis, which only considers the unavoidable exergy destruction, is conducted for single,
double, triple and half effect Water–Lithium bromide absorption cycles. Thus, the obtained performances
represent the maximum achievable performance under the given operation conditions.
The coefficient of performance (COP), the exergetic efficiencies and the exergy destruction rates are
determined and the effect of the heat source temperature is evaluated. As expected, the COP increases
significantly from double lift to triple effect cycles. The exergetic efficiency varies less among the
different configurations. In all cycles the effect of the heat source temperature on the exergy destruction
rates is similar for the same type of components, while the quantitative contributions depend on cycle
type and flow configuration. Largest exergy destruction occurs in the absorbers and generators, especially
at higher heat source temperatures.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier Ltd., 2010
Absorption cycle
Water–Lithium bromide
Exergy analysis
Double effect
Exergy analysis of multi-effect water–LiBr absorption systems: From half to triple effect
article
oai:repositori.udl.cat:10459.1/4631782023-04-13T03:00:29Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56946
Rubies, Elena
Bitriá, Ricard
Clotet Bellmunt, Eduard
Palacín Roca, Jordi
2023-04-12T11:20:57Z
2023-04-12T11:20:57Z
2023
https://doi.org/10.3390/app13063971
2076-3417
https://repositori.udl.cat/handle/10459.1/463178
This work proposes an Internet-of-Things (IoT) device for remote elevator control. The new contribution of this proposal to the state-of-the-art is that it can convert a manually operated elevator into a remote controlled elevator without requiring any intrusive manipulation or wiring connection in the elevator. This IoT device has been designed as an add-on non-contact tool which is placed over the original elevator button panel, using servomotors to press the original buttons. This design allows its fast deployment as a remote control tool that increases elevator accessibility through the use of messages, a webpage or a QR code. Some application examples of this proposal are non-contact use of elevators in pandemic conditions, and the unsupervised use of elevators by autonomous cleaning or delivery mobile robots. The experimental evaluation of the IoT device in real operational conditions has validated its non-contact control features.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Elena Rubies et al., 2023
Attribution 4.0 International
Elevator
Lift
Internet-of-Things;
Non-contact
Non-intrusive
Wireless control
Non-Contact and Non-Intrusive Add-on IoT Device for Wireless Remote Elevator Control
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/647332022-10-10T17:24:23Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Zsembinszki, Gabriel
Solé, Aran
Barreneche Güerisoli, Camila
Prieto, Cristina
Fernández Renna, Ana Inés
Cabeza, Luisa F.
2018-09-19T11:35:29Z
2018-09-19T11:35:29Z
2018
https://doi.org/10.3390/en11092358
027330
1996-1073
http://hdl.handle.net/10459.1/64733
The aim of this study is to perform a review of the state-of-the-art of the reactors available in the literature, which are used for solid-gas reactions or thermal decomposition processes around 1000 ºC that could be further implemented for thermochemical energy storage in CSP (concentrated solar power) plants, specifically for SPT (solar power tower) technology. Both direct and indirect systems can be implemented, with direct and closed systems being the most studied ones. Among direct and closed systems, the most used configuration is the stacked bed reactor, with the fixed bed reactor being the most frequent option. Out of all of the reactors studied, almost 70% are used for solid-gas chemical reactions. Few data are available regarding solar efficiency in most of the processes, and the available information indicates relatively low values. Chemical reaction efficiencies show better values, especially in the case of a fluidized bed reactor for solid-gas chemical reactions, and fixed bed and rotary reactors for thermal decompositions.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Zsembinszki, Gabriel et al., 2018
High temperature
Concentrated solar power (CSP)
Thermochemical energy storage (TCM)
Solid–gas reactors
Review
Review of Reactors with Potential Use in Thermochemical Energy Storage in Concentrated Solar Power Plants
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/585772017-03-10T13:31:52Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Pérez Luque, Gabriel
Vila, Anna
Solé Cutrona, Cristian
Coma Arpón, Julià
Castell, Albert
Cabeza, Luisa F.
2016-11-18T10:54:48Z
2016-11-18T10:54:48Z
2015
https://doi.org/10.1007/s12053-015-9329-3
022335
1570-646X
http://hdl.handle.net/10459.1/58577
Green infrastructure for buildings, such as extensive green roofs, can improve the urban environment. Previous experimental studies confirm the benefits of these systems from different approaches: energy, hydraulics, materials, etc. But, it is necessary to obtain data about its behaviour in real cases, where conditions could be very heterogeneous: different surface finish, low vegetation cover in first years, lack of maintenance, etc. In this article, different aspects about this topic are discussed. Moreover, the results of monitoring a real extensive green roof during the first year after plantation in order to study the thermal behaviour are presented. In these conditions of low plant cover (10 %), the main conclusions refer to the substrate, which although it preserves cool near the base roof, it heated and cooled very quickly. This fact confirms that the substrate limited thermal mass effect, due basically to its composition and small thickness. The material composition and the thickness of the substrate should be studied in depth because it can affect the thermal performance of the roof.
eng
info:eu-repo/semantics/openAccess
(c) Springer Science+Business Media Dordrecht, 2015
Green infrastructure
Extensive green roof
Ecological roof
Passive energy system
Thermal behaviour
Building
The thermal behaviour of extensive green roofs under low plant coverage conditions
article
oai:repositori.udl.cat:10459.1/831752022-10-04T16:42:00Zcom_10459.1_238com_10459.1_2col_10459.1_309col_10459.1_49291
Vérez, David
Borri, Emiliano
Cabeza, Luisa F.
2022-04-28T10:44:32Z
2022-04-28T10:44:32Z
2022
https://doi.org/10.3390/en15093047
032400
1996-1073
http://hdl.handle.net/10459.1/83175
According to the Intergovernmental Panel on Climate Change (IPCC) 5th Assessment report, energy-efficient appliances can reduce global electricity consumption even though there is an expected increase in the number and ownership of appliances. The International Energy Agency (IEA) expects a high increase in energy efficiency in traditional appliances (refrigerators, washing machines, television, etc.), and in the number of new appliances installed (also called plug loads). The bibliometric study of publications related to energy-efficient appliances carried out in this paper shows that research on this topic is growing in developed regions (North America and Europe) and even more in some developing regions (Asia Pacific) with a high emphasis on China and India. The results indicate that, in general, policies are always implemented before the core of publications on the topic, with time spans ranging from 3 to 30 years. However, the trend seems to be changing with publications related to new appliances where the core research happens shortly after or in parallel to the establishment of policies.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Vérez, David et al., 2022
Energy efficiency
Appliance
Climate change
Policies
Label
Bibliometric analysis
Trends in research on energy efficiency in appliances and correlations with energy policies
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/702482023-05-23T10:26:25Zcom_10459.1_238com_10459.1_2com_10459.1_72344col_10459.1_309col_10459.1_72345
Ollé i Otero, Lluís
Baquero Armans, Grau
Solé Ferrer, Maria Mercè
Cuadros Domènech, Rosa
Bacardit i Dalmases, Anna
2021-01-18T11:53:46Z
2021-01-18T11:53:46Z
2016-08
https://doi.org/10.1016/j.jclepro.2016.04.134
027566
0959-6526
http://hdl.handle.net/10459.1/70248
Today, the first stages of the finishing processes of buffed cattle hides or full loose grain–known as impregnation–are largely carried out with acrylic resins and penetrating agents (typically, a mixture of surfactants and solvents). This application aims to strengthen the partially buffed grain layer bound to the rest of the dermis. To that end, a composition of emulsified acrylic resins is used, as
well as a penetrating agent – usually isopropyl alcohol –, and water. The process examined consists in the application of acrylic polymers in an aqueous emulsion that, because of their structure, size, and properties no longer require the use of the isopropyl alcohol contained in the penetrating
agents. The use of this alcohol causes adverse effects on the health of workers that are exposed to emanations of isopropanol vapors (irritant to eyes, respiratory tract, and skin) in the work environment. Effects from prolonged exposition and inhalation may lead to headaches, dizziness, drowsiness, nausea and, ultimately, to unconsciousness. By using the new polymers developed in this work, the negative environmental effects of the finishing process can be minimized. At the same time, the use of these highly carboxylate resins avoid the exposure to isopropyl alcohol, which is
harmful to the health. In addition, the volatile organic compounds (VOC) are reduced without compromising the appearance, performance and fashion requirements that are expected in the final product.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd, (c) Elsevier, 2016
Carboxylate resin
Impregnation
Isopropyl alcohol
Leather finishing
Application of highly carboxylate resins in aqueous emulsion for leather coating avoiding the use of isopropyl alcohol
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/478862022-11-15T14:41:01Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Cabeza, Luisa F.
Rincón, Lídia
Vilariño, Virginia
Pérez Luque, Gabriel
Castell, Albert
2015-02-09T08:05:42Z
2014
https://doi.org/10.1016/j.rser.2013.08.037
020013
1364-0321
http://hdl.handle.net/10459.1/47886
This review summarizes and organizes the literature on life cycle assessment (LCA), life cycle energy analysis (LCEA) and life cycle cost analysis (LCCA) studies carried out for environmental evaluation of
buildings and building related industry and sector (including construction products, construction systems, buildings, and civil engineering constructions). The review shows that most LCA and LCEA are carried out in what is shown as “exemplary buildings”, that is, buildings that have been designed and constructed as low energy buildings, but there are very few studies on “traditional buildings”, that is, buildings such as
those mostly found in our cities. Similarly, most studies are carried out in urban areas, while rural areas are not well represented in the literature. Finally, studies are not equally distributed around the world.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2013
Life Cycle Assessment
Life cycle energy analysis
Life cycle cost analysis
Life cycle assessment (LCA) and life cycle energy analysis (LCEA) of buildings and the building sector: A review
article
oai:repositori.udl.cat:10459.1/711662022-10-20T16:57:55Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Maldonado, José Miguel
Vérez, David
Gracia Cuesta, Alvaro de
Cabeza, Luisa F.
2021-04-27T11:21:50Z
2021
https://doi.org/10.1016/j.applthermaleng.2021.116974
031244
1359-4311
http://hdl.handle.net/10459.1/71166
This paper experimentally evaluates the implementation of heat pipes in latent heat thermal energy storage systems. The well-known performance of heat pipes as a heat transfer technology makes them great candidates to be used as heat exchangers. However, previous studies compared their efficacy against solid metal rods, where heat pipes clearly succeeded. Therefore, the objective of this study is to experimentally evaluate the advantages of using heat pipes instead of a common shell and tubes system, during charging processes. In particular, five latent heat thermal energy storage systems were tested. One based on the shell and tubes, and the remaining four based on heat pipes. The experiments were conducted at constant heat transfer fluid temperature and flow rate, and the results were analysed from the temperature, heat transfer, and visual point of view. The results show that in heat pipes systems the phase change material melts homogeneously through all the storage container. However, the shell and tubes tank performed the charging process in 25 min while the fastest heat pipe one took 40 min for it. On the other hand, in the shell and tubes configuration melt from the heat transfer fluid inlet towards the outlet. Moreover, systems with more heat pipe surface inside the heat transfer fluid collector rovided higher power rates. Comparing the best and the worst heat pipe storage tanks during the first 30 min, the heat transfer rate increased over 40%. But the storing material low conductivity cushioned those high heat transfer rates.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Maldonado et al., 2021
Latent heat thermal energy storage (LHTES)
Phase change material (PCM)
Heat pipes
Heat exchanger
Experimental analysis
Comparative study between heat pipe and shell-and-tube thermal energy storage
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/479122021-08-30T15:04:30Zcom_10459.1_238com_10459.1_2col_10459.1_309col_10459.1_49291
Medrano Martorell, Marc
Castell, Albert
Fontanals, Gerard
Castellón, Cecilia
Cabeza, Luisa F.
2015-02-10T13:11:52Z
2008
https://doi.org/10.1016/j.applthermaleng.2007.12.019
011677
1359-4311
http://hdl.handle.net/10459.1/47912
A new research university building with a useful area of about 3000 m2 has recently been constructed in Lleida (Spain) as an example
of a sustainable energy efficient institutional building. The building is provided with passive measures in the envelope as well as a wide
variety of active measures in the installed energy systems. Non-conventional energy systems such as solar photovoltaic arrays, thermal
collectors, an internal combustion engine cogeneration, and an absorption chiller are in place. The standard systems, namely two 320 kW
condensation boilers and a 419 kW compression chiller, are also included in the building for back-up and for comparison purposes. To
assess the potential energy, economic and CO2 savings of the building a simplified model is developed and the main results discussed. For
nominal electricity and gas average prices about 11.5 k€ of savings are achieved. This represents energy cost reductions of 35–58%, a
payback period of 20 years and about 56 tons per year of saved CO2 emissions. The presence of the absorption chiller is found essential
to maximize buildings economic and CO2 emissions savings. This work also includes parametric studies for natural gas and electricity
prices as well as results for other possible combinations with only one or several of the installed systems in operation.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2008
Institutional building
Trigeneration
Economic analysis
Economics and climate change emissions analysis of a bioclimatic institutional building with trigeneration and solar support
article
oai:repositori.udl.cat:10459.1/493522023-01-27T14:57:23Zcom_10459.1_56965com_10459.1_2com_10459.1_243com_10459.1_238com_10459.1_49298col_10459.1_57707col_10459.1_3332col_10459.1_309col_10459.1_49299col_10459.1_49291
Rosell Polo, Joan Ramon
Llorens Calveras, Jordi
Sanz Cortiella, Ricardo
Arnó Satorra, Jaume
Ribes Dasi, Manuel
Masip Vilalta, Joan
Escolà i Agustí, Alexandre
Camp, Ferran
Solanelles Batlle, Francesc
Gràcia, Felip
Gil Moya, Emilio
Val, Luis
Planas de Martí, Santiago
Palacín Roca, Jordi
2016-01-20T12:07:22Z
2016-01-20T12:07:22Z
2009
https://doi.org/10.1016/j.agrformet.2009.04.008
013542
0168-1923
http://hdl.handle.net/10459.1/49352
In recent years, LIDAR (light detection and ranging) sensors have been widely used to measure environmental parameters such as the structural characteristics of trees, crops and forests. Knowledge of the structural characteristics of plants has a high scientific value due to their influence in many biophysical processes including, photosynthesis, growth, CO2-sequestration and evapotranspiration, playing a key role in the exchange of matter and energy between plants and the atmosphere, and affecting terrestrial, above-ground, carbon storage. In this work, we report the use of a 2D LIDAR scanner in agriculture to obtain three-dimensional (3D) structural characteristics of plants. LIDAR allows fast, non-destructive measurement of the 3D structure of vegetation (geometry, size, height, cross-section, etc.). LIDAR provides a 3D cloud of points, which is easily visualized with Computer Aided Design software. Three-dimensional, high density data are uniquely valuable for the qualitative and quantitative study of the geometric parameters of plants. Results are demonstrated in fruit and citrus orchards and vineyards, leading to the conclusion that the LIDAR system is able to measure the geometric characteristics of plants with sufficient precision for most agriculture applications. The developed system made it possible to obtain 3D digitalized images of crops, from which a large amount of plant information – such as height, width, volume, leaf area index and leaf area density – could be obtained. There was a great degree of concordance between the physical dimensions, shape and global appearance of the 3D digital plant structure and the real plants, revealing the coherence of the 3D tree model obtained from the developed system with respect to the real structure. For some selected trees, the correlation coefficient obtained between manually measured volumes and those obtained from the 3D LIDAR models was as high as 0.976.
eng
info:eu-repo/semantics/openAccess
(c) Elsevier, 2009
Terrestrial LIDAR
Laser measurements
3D Plant structure
Tree volume
Obtaining the three-dimensional structure of tree orchards from remote 2D terrestrial LIDAR scanning
article
oai:repositori.udl.cat:10459.1/685292022-12-21T09:41:40Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Cabeza, Luisa F.
Chàfer, Marta
2020-05-04T07:45:08Z
2022-04-15T22:08:53Z
2020
https://doi.org/10.1016/j.enbuild.2020.110009
029966
0378-7788
http://hdl.handle.net/10459.1/68529
A systematic review of the technological options and strategies to achieve zero energy buildings was carried out to establish today state-of-the-art knowledge base and to present key design and performance factors that define those technologies with the final aim of contributing to climate change mitigation options of buildings. All relevant literature published from January 2013 to August 2019 was critically as- sessed. A total of 14,895 papers were identified and 220 reviews were evaluated as first literature source; this literature showed that the published information is diverse and not organized, therefore climates and building typologies is not possible solely through published information. Collected evidence shows that with appropriate design, buildings can contribute to climate change mitigation decreasing the embodied energy in the materials used in their construction and decreasing the energy demand and use during their operation phase.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd (c) Elsevier, 2020
Buildings
Zero energy buildings
Climate change mitigation
Technological options
Technological options and strategies towards zero energy buildings contributing to climate change mitigation: A systematic review
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/645872022-09-28T20:34:36Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Olivieri, Lorenzo
Tenorio, José Antonio
Revuelta Crespo, David
Navarro Farré, Lidia
Cabeza, Luisa F.
2018-07-04T10:26:06Z
2020-06-15T22:09:31Z
2018
https://doi.org/10.1016/j.conbuildmat.2018.06.013
027179
0950-0618
http://hdl.handle.net/10459.1/64587
This work presents an experimental research on the thermal properties of novel cementitious mortars incorporating microencapsulated Phase Change Materials intended to be used as the innermost layer in a precast radiant building component actively controlled by an integrated hydronic system. The characterization was developed in two steps: the first one focused on the effects of different fine aggregates and admixtures for a fixed PCM content and the second one on the effect of changing the amount of PCM. Results show that using silica aggregates and antifoaming admixture outperform the other options, producing mortars with statistically significant higher thermal conductivities, diffusivities and effusivities. Besides, increasing the amount of PCM significantly reduces conductivity and diffusivity, but the effusivity is practically invariant. This suggests that the mortar design has to be defined by predominantly focusing on diffusivity, in order to achieve appropriate heat penetration rates and activation times for an efficient system operation.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/es
cc-by-nc-nd (c) Elsevier, 2018
Phase Change Material
Thermal energy storage
Thermal diffusivity
Thermal effusivity
Cementitious mortar
Developing a PCM-enhanced mortar for thermally active precast walls
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/477872021-08-30T15:04:30Zcom_10459.1_238com_10459.1_2col_10459.1_309col_10459.1_49291
Castell, Albert
Martorell, Ingrid
Medrano Martorell, Marc
Pérez Luque, Gabriel
Cabeza, Luisa F.
2015-02-02T10:46:50Z
2010
https://doi.org/10.1016/j.enbuild.2009.10.022
014379
0378-7788
http://hdl.handle.net/10459.1/47787
This work presents the results of an experimental set-up to test phase change materials with two typical
construction materials (conventional and alveolar brick) for Mediterranean construction in real
conditions. Several cubicles were constructed and their thermal performance throughout the time was
measured. For each construction material, macroencapsulated PCM is added in one cubicle (RT-27 and
SP-25 A8). The cubicles have a domestic heat pump as a cooling system and the energy consumption is
registered to determine the energy savings achieved. The free-floating experiments show that the PCM
can reduce the peak temperatures up to 1 8C and smooth out the daily fluctuations. Moreover, in summer
2008 the electrical energy consumption was reduced in the PCM cubicles about 15%. These energy
savings resulted in a reduction of the CO2 emissions about 1–1.5 kg/year/m2.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2009
PCM
Buildings
Energy savings
Experimental study of using PCM in brick constructive solutions for passive cooling
article
oai:repositori.udl.cat:10459.1/477892022-10-17T19:25:06Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Castellón, Cecilia
Medrano Martorell, Marc
Roca Enrich, Joan
Cabeza, Luisa F.
Navarro, Maria E.
Fernández Renna, Ana Inés
Lázaro, Ana
Zalba, Belén
2015-02-02T10:53:50Z
2010
https://doi.org/10.1016/j.renene.2010.03.030
015180
0960-1481
http://hdl.handle.net/10459.1/47789
Sandwich panels are a good option as building materials, as they offer excellent characteristics in
a modular system. The goal of this study was to demonstrate the feasibility of using the microencapsulated
PCM (Micronal BASF) in sandwich panels to increase their thermal inertia and to reduce
the energy demand of the final buildings. In this paper, to manufacture the sandwich panel with
microencapsulated PCM three different methods were tested. In case 1, the PCM was added mixing the
microencapsulated PCM with one of the components of the polyurethane. In the other two cases, the
PCM was added either a step before (case 2) or a step after (case 3) to the addition of the polyurethane
to the metal sheets. The results show that in case 1 the effect of PCM was overlapped by a possible
increase in thermal conductivity, but an increase of thermal inertia was found in case 3. In case 2,
different results were obtained due to the poor distribution of the PCM. Some samples showed the
effect of the PCM (higher thermal inertia), and other samples results were similar to the conventional
sandwich panel. In both cases (2 and 3), it is required to industrialize the process to improve
the results.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2010
Sandwich panel
Phase change material
Thermal energy storage
Effect of microencapsulated phase change material in sandwich panels
article
oai:repositori.udl.cat:10459.1/734452023-09-13T14:02:21Zcom_10459.1_238com_10459.1_2com_10459.1_72344col_10459.1_309col_10459.1_72345
Conde Mateos, Mireia
Combalia Cendra, Felip
Baquero Armans, Grau
Ollé i Otero, Lluís
Bacardit i Dalmases, Anna
2022-03-29T07:13:05Z
2022-03-29T07:13:05Z
2022
https://doi.org/10.1016/j.clet.2022.100425
032050
2666-7908
http://hdl.handle.net/10459.1/73445
The use of vegetable tannins is a bio-based alternative to chrome tanning. The most used vegetable extracts are Mimosa and Quebracho. To improve the sustainability of the tanning process, a chemically unmodified pine bark could be used as a natural source of tannins. The present study was aimed to evaluate the environmental impact of the use of pine bark powder to obtain vegetable leather through a life cycle assessment. Specifically, the life cycle impact evaluation was performed for both: i) pine bark powder tannin and the atomized mimosa extract production as raw material; and ii) the production process of a tanned leather with pine bark tannin versus a tanned leather with mimosa extract. An eco-friendly and cleaner production method for obtaining pine bark powder was developed. This new production method allows to obtain a reduction in 83% in the 'climate change' impact category. However, when this tannin is applied to obtain a tanned leather, the tanning process shows an increase in all studied impact categories compared with the use of the atomized mimosa extract.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd (c) Mireia Conde et al., 2022
Life cycle impact assessment
Global warming potential
Pine bark
Mimosa tannin
Vegetable tanning
Exploring the feasibility of substituting mimosa tannin for pine bark powder. A LCA perspective
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/477452021-08-30T15:04:35Zcom_10459.1_238com_10459.1_2col_10459.1_309
Cabeza, Luisa F.
Taylor, M. M.
DiMaio, G. L.
Brown, E. M.
Marmer, W. N.
Carrió, R.
Celma Serra, Pedro
Cot Gores, Jaume
2015-01-28T09:28:41Z
1998
https://doi.org/10.1016/S0956-053X(98)00032-4
004331
0956-053X
http://hdl.handle.net/10459.1/47745
Hides come to the tanner as a by-product of the meat industry. The tanning process, in turn, generates much greater quantities of by-products and wastes than leather. One ton of wet salted hides yields only 200 kg of leather but over 600 kg of solid waste, or by- product if a market can be found. In the United States, nearly 60,000 metric tons of chromium-containing solid waste, i.e. chrome shavings, are generated by the leather industry each year, and approximately ten times this amount is generated worldwide. Land application for the disposal of chromium-containing tannery and other leather wastes has been widely practiced during most of the twentieth century, but fewer landfill sites can be found every day and the cost of transportation and disposal increases. Historically, these materials were used in the production of fertilizer or composite boards, but while once the company producing and marketing fertilizer or boards would pay for the waste and its transportation, nowadays, the tanner has to pay for such things. Over several years, we have demonstrated that it is possible to isolate protein products (gelatin and collagen hydrolysate) from chrome shavings by using an alkaline protease under mild conditions. The objective of the present work was to perform pilot plant trials to isolate protein products from chrome shavings, treat and purify the remaining chrome cake and tan hides with the recovered chromium. Because of the high nitrogen content, the isolated collagen hydrolysate has potential use as a fertilizer and in animal feed additives. The gelatin has potential use in cosmetics, adhesives, printing, photography, microencapsulation, films or even as an additive in finishing products for the leather industry.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier Science, 2003
Processing of leather waste: pilot scale studies on chrome shavings. Isolation of potentially valuable protein products and chromium
article
oai:repositori.udl.cat:10459.1/664672021-08-27T14:37:30Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941
Petrichenko, Ksenia
Ürge-Vorsatz, Diana
Cabeza, Luisa F.
2019-06-19T11:15:15Z
2021-06-11T22:30:03Z
2019
https://doi.org/10.1016/j.enbuild.2019.06.024
028669
0378-7788
http://hdl.handle.net/10459.1/66467
With the Paris Agreement coming into force, global efforts will need to maximize opportunities through energy efficiency and renewable energy generation. Zero energy/carbon initiatives are mushrooming worldwide, but it has not been fully understood which building types in which climates and under which conditions can potentially be built to net zero energy standards. In order to inform these efforts, a new model was developed to estimate the technical potential for building¿integrated solar energy (BISE, the name of the model) generation in a high resolution regional, climate and building typology breakdown., The BISE model also evaluates the opportunities for potential net zero energy buildings based on the BISE findigns, combining these with the findings of two global low-energy building models. The BISE model has a very high resolution in terms of geographic regions, climate types, building types and vin- tages. Moreover, the model combines methods for bottom-up energy modeling and geospatial analysis. The thermal building energy demand estimation is based on the 3CSEP-HEB model and the plug load scenarios are based on the BUENAS model. Results are wide, due to intrinsic limitationso of the model detailed in the paper, but it is shown that there is a substantial potential for building-integrated solar energy generation in all world regions, and that the Deep Efficiency Scenario allows significantly more building types to meet net zero energy levels by 2050 in contrast to a scenario when only moderate energy efficiency improvements are implemented.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd (c) Elsevier, 2019
Solar energy
Potentials
Energy efficiency
Net zero energy buildings
Modeling
Geospatial analysis
Modeling global and regional potentials for building-integrated solar energy generation
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/665092022-09-27T20:30:20Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Prieto, Cristina
Rodríguez-Sánchez, Alfonso
Ruiz-Cabañas, F. Javier
Cabeza, Luisa F.
2019-07-02T10:19:36Z
2019-07-02T10:19:36Z
2019
https://doi.org/10.3390/en12122340
028680
1996-1073
http://hdl.handle.net/10459.1/66509
Parabolic trough collector (PTC) technology is currently the most mature solar technology, which has led to the accumulation of relevant operational experience. The overall performance and efficiency of these plants depends on several components, and the heat transfer fluid (HTF) is one of the most important ones. Using molten salts as HTFs has the advantage of being able to work at higher temperatures, but it also has the disadvantage of the potential freezing of the HTF in pipes and components. This paper models and evaluates two methods of freeze recovery, which is needed for this HTF system design: Heat tracing in pipes and components, and impedance melting in the solar field. The model is used to compare the parasitic consumption in three molten salts mixtures, namely Solar Salt, HiTec, and HiTec XL, and the feasibility of this system in a freezing event. After the investigation of each of these subsystems, it was concluded that freeze recovery for a molten salt plant is possible.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0
cc-by (c) Prieto, Cristina et al., 2019
Parabolic trough collector
Molten salt
Freeze recovery
Heat tracing
Impedance melting
Feasibility Study of Freeze Recovery Options in Parabolic Trough Collector Plants Working with Molten Salt as Heat Transfer Fluid
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/710722021-04-21T00:18:39Zcom_10459.1_238com_10459.1_2col_10459.1_309
Riba Ruiz, Jordi-Roger
Canals, Trini
Cantero Gómez, M. Rosa
2021-04-20T09:13:48Z
2021-04-20T09:13:48Z
2012-04
https://doi.org/10.1109/TIM.2011.2173048
027861
0018-9456
http://hdl.handle.net/10459.1/71072
Recycled paper is extensively used worldwide. In the last decades, its market has expanded considerably. The increasing use of recycled paper in papermaking has led to the production of paper containing several types of impurities. Consequently, wastepaper mills are forced to implement quality control schemes for evaluating the incoming wastepaper stock, thus guarantying the specifications of the final product. The main objective of this work is to present a fast and reliable system for identifying different paper types. Therefore, undesirable paper types can be refused, improving the performance of the paper machine and the final quality of the paper manufactured. For this purpose, two fast techniques, i.e., Fourier transform midinfrared (FTIR) and reflectance near infrared (NIR), were applied to acquire the infrared spectra of the paper samples. Next, four processing multivariate methods, i.e., principal component analysis, canonical variate analysis (CVA), extended CVA (ECVA), and support vector machines (SVMs), were employed in the feature-extraction or dimension-reduction stage. Afterward, the k nearest neighbor ( k NN) algorithm was used in the classification phase. Experimental results show the usefulness of the proposed methodology and the potential of both FTIR and NIR spectroscopic methods. Using the FTIR spectrum in association with SVM and k NN, the system achieved a maximum classification accuracy of 100%, whereas using the NIR spectrum in association with ECVA or SVM and k NN, the system achieved a maximum classification accuracy of 96.4%.
eng
info:eu-repo/semantics/openAccess
(c) IEEE, 2012
Infrared spectroscopy
Multivariate methods
Paper finish
Process control
Quality improvement
Comparative study of multivariate methods to identify paper finishes ssing infrared spectroscopy
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/477692017-05-10T09:49:58Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291col_10459.1_44504
Cabeza, Luisa F.
Gutiérrez, Andrea
Barreneche Güerisoli, Camila
Ushak, Svetlana
Fernández, Ángel G.
Fernández Renna, Ana Inés
Grágeda, Mario
2015-01-29T09:36:19Z
2017-02-01T23:51:52Z
2015
https://doi.org/10.1016/j.rser.2014.10.096
021783
1364-0321
http://hdl.handle.net/10459.1/47769
Lithium, mainly used in electrical energy storage, has also been studied in thermal energy storage. It is recognized as a"critical material" and is produced from minerals and from brines. Chile is one of the biggest producers, here from brine and with lower costs than in other countries. With sensible heat storage, in solar power plants lithium is seen as a way to improve the properties of molten salts used today. The low melting point in these ternary salts with lithium, represent a considerable reduction in the maintenance and operational costs associated with current solar technology, demonstrating that the fluids showed, are potential candidates for thermal energy storage (TES) in concentrated solar plants (CSP) plants. Many materials have been studied and proposed to be used as phase change materials (PCM). Between the multiple materials studied to be used in PCM, lithium materials and mixtures are listed as potential PCM for building applications and for high temperature applications. In thermochemical energy storage, lithium compounds have been used mainly in chemical heat pumps, following their use in absorption cooling.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd, (c) Elsevier, 2015
Lithium in thermal energy storage: a state-of-the-art review
oai:repositori.udl.cat:10459.1/577662023-12-05T08:55:56Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291col_10459.1_44504
Marín, Paula E.
Saffari Tabalvandani, Mohammad
Gracia Cuesta, Alvaro de
Zhu, Xibingyan
Farid, Mohammed M.
Cabeza, Luisa F.
Ushak, Svetlana
2016-09-02T10:16:15Z
2018-10-01T22:18:48Z
2016
https://doi.org/10.1016/j.enbuild.2016.08.007
024585
0378-7788
http://hdl.handle.net/10459.1/57766
Relocatable, transportable or off-site constructed lightweight buildings typically undergo sharp indoor temperature fluctuations in the heating and cooling seasons due to the lack of sufficient thermal mass in their envelopes, resulting in high energy consumption to provide the zone with comfort temperature. The application of phase change materials has been suggested as a promising solution to control the indoor thermal condition in buildings. This work is an attempt to support the application of PCM technology in lightweight relocatable buildings as a passive alternative to save energy under different weather conditions. The numerical results highlighted the potential of using PCM-enhanced gypsum boards in lightweight buildings to increase the energy performance during both heating and cooling seasons in arid and warm temperate main climate areas.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd (c) Elsevier, 2016
Thermal energy storage (TES)
Phase change material (PCM)
Passive heating and cooling
Simulation
Energy savings due to the use of PCM for relocatable lightweight buildings passive heating and cooling in different weather conditions
article
oai:repositori.udl.cat:10459.1/487242021-08-30T15:04:35Zcom_10459.1_238com_10459.1_2col_10459.1_309
Rojo, Naiara
Prenafeta-Boldú, Francesc Xavier
Illa i Alibés, Josep
Gallastegui, Gorka
Guivernau, Miriam
Elías, Ana
Barona, Astrid
2015-09-17T13:57:17Z
2015-04-14
https://doi.org/10.1016/j.ces.2015.03.062
023026
0009-2509
http://hdl.handle.net/10459.1/48724
Black slag from an electric arc furnace (EAF) was used as an innovative inorganic co-packing material in organic biofilters for the biodegradation of CS2-polluted gases. The effect on biofilter performance of increasing the inlet concentration (IC) and reducing the empty bed residence time (EBRT) was evaluated in three biofilters packed with different bed configurations. Macrokinetic modelling pointed to a lower CS2 biodegradation activity related to the presence of the slag. Nevertheless, the presence of black slag improved long-term biofilter performance, and the maximum elimination capacity (43 g m−3 h−1) was recorded in the biofilter packed with a mixed support. Molecular profiling of the eubacterial populations demonstrated the ubiquitous presence of the potential CS2 degrading species Thiomonas intermedia. Co-packing with EAF slag also prompted the development of a more complex microbial community encompassing halophilic species involved in the metabolism of sulphur compounds (i.e. Thiohalophilus spp. and Paracoccus thiocyanatus).
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2015
Bioreparació
Downstream bioprocessing of CS2-polluted emissions: innovative use of a black slag in mixed biofilters
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/674422022-10-27T11:34:45Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Canela Xandri, Anna
Villorbina Noguera, Gemma
Balcells Fluvià, Mercè
Fernández Francos, Xavier
Cabeza, Luisa F.
Canela i Garayoa, Ramon
2019-11-04T07:53:18Z
2019-11-04T07:53:18Z
2019
https://doi.org/10.3390/molecules24203777
029109
1420-3049
http://hdl.handle.net/10459.1/67442
Nine monoamides were synthesized from carboxylic acids (C8-C18) and crude glycerol. The final monoamides were the result of a rearrangement of the acyl chain during the final hydrogenation process. The purity of the final compounds was determined by spectroscopic and mass spectrometry (MS) techniques. The thermophysical properties of solid monoamides were investigated to determine their capability to act as phase change materials (PCM) in thermal energy storage. Thermophysical properties were determined with a di erential scanning calorimeter (DSC). The melting temperatures of the analyzed material ranged from 62.2 C to 116.4 C. The analyzed enthalpy of these monoamides ranged from 25.8 kJ/kg to 149.7 kJ/kg. Enthalpy values are analyzed considering the carbon chain and the formation of hydrogen bonds.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/3.0/es
cc-by (c) Canela Xandri, Anna et al., 2019
Alkyl monoamides
Glycerol
Hydrogen bond
PCM
TES
Synthesis and Thermophysical Characterization of Fatty Amides for Thermal Energy Storage
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/597302019-06-27T08:30:07Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941
Cabeza, Luisa F.
Schossig, Peter
2017-05-29T14:25:05Z
2019-06-06T22:15:17Z
2017
https://doi.org/10.1016/j.renene.2017.04.054
025657
0960-1481
http://hdl.handle.net/10459.1/59730
At present there is important R&D in the field of sorption heating, cooling and thermal energy storage systems going on worldwide. Sorption systems can enable a more efficient use of renewable energies (solar, geothermal, etc.) both for domestic and industrial applications. This special issue presents the recent advances in the following key-sorption technologies:
•
Ad-sorption and ab-sorption closed- cycle heat pumps and chillers.
•
Ad-sorption and ab-sorption open-cycle systems for air conditioning, dehumidification, solar cooling, etc.
•
Sorption and thermochemical systems for thermal energy storage.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd, (c) Elsevier, 2017
Calefacció -- Instal·lacions
Refrigeració -- Instal·lacions
Advances in sorption systems for energy efficient heating and cooling
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/598472023-03-27T12:30:26Zcom_10459.1_238com_10459.1_2com_10459.1_239col_10459.1_309col_10459.1_10984
Moreno Blanc, Javier
Clotet Bellmunt, Eduard
Tresánchez Ribes, Marcel
Martínez Lacasa, Daniel
Casanovas Salas, Jordi
Palacín Roca, Jordi
2017-06-13T10:32:28Z
2017-06-13T10:32:28Z
2017
https://doi.org/10.3390/s17051122
025656
1424-8220
http://hdl.handle.net/10459.1/59847
This paper presents the vibration pattern measurement of two tower-typed holonomic mobile robot prototypes: one based on a rigid mechanical structure, and the other including a passive suspension system. Specific to the tower-typed mobile robots is that the vibrations that originate in the lower part of the structure are transmitted and amplified to the higher areas of the tower, causing an unpleasant visual effect and mechanical stress. This paper assesses the use of a suspension system aimed at minimizing the generation and propagation of vibrations in the upper part of the tower-typed holonomic robots. The two robots analyzed were equipped with onboard accelerometers to register the acceleration over the X, Y, and Z axes in different locations and at different velocities. In all the experiments, the amplitude of the vibrations showed a typical Gaussian pattern which has been modeled with the value of the standard deviation. The results have shown that the measured vibrations in the head of the mobile robots, including a passive suspension system, were reduced by a factor of 16.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/3.0/es
cc-by (c) Moreno Blanc, Javier et al., 2017
Measurement of vibrations in two tower-typed assistant personal robot implementations with and without a passive suspension system
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/478022021-08-30T15:04:27Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Lázaro, Ana
Peñalosa, Conchita
Solé, Aran
Diarce, Gonzalo
Haussmann, Thomas
Fois, Magali
Zalba, Belén
Gschwander, Stefan
Cabeza, Luisa F.
2015-02-03T08:21:45Z
2013
https://doi.org/10.1016/j.apenergy.2012.11.045
018611
0306-2619
http://hdl.handle.net/10459.1/47802
For the correct design of thermal storage systems using phase change materials (PCMs) in any application,
as well as for their simulation, it is essential to characterise the materials from thermophysical
and rheological standpoints (phase change enthalpy, thermal conductivity in solid and liquid phases, viscosity
and density in function of temperature). Taking advantage of the different research groups facilities
available in two international networks: within the IEA (International Energy Agency), the ECES Implementing
Agreement (Energy Conservation through Energy Storage IA) and SHC Programme (Solar Heating
and Cooling) Task 42/Annex 24 ‘‘Compact Thermal Energy Storage – Material Development for System
Integration’’, and the COST Action TU0802 ‘‘Next generation cost effective phase change materials for
increased energy efficiency in renewable energy systems in buildings (NeCoE-PCM)’’ a set of Round Robin
Tests (RRTs) was proposed. The objective was to come to comparable results for PCMs using Differential
Scanning Calorimetry (DSC) to determine their melting enthalpy as well as their melting and solidification
behaviour. The first RRT was without defining the procedure, the second one with a predefined procedure
for the measurements, but not for calibration and the third one with a predefined procedure for
calibration, for the measurements and also for the data evaluation. This paper presents the conclusions
after the three RRT. The main conclusion of the paper is that enthalpy in function of temperature determined
using a dynamic method for DSC can be influenced by certain reasons and finally a methodology to
avoid these influences have been proposed.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2012
Phase change materials
Enthalpy
Differential Scanning Calorimetry
Intercomparative tests on phase change materials characterisation with differential scanning calorimeter
article
oai:repositori.udl.cat:10459.1/578612022-10-10T17:00:47Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291col_10459.1_44504
Serrano, Susana
Barreneche Güerisoli, Camila
Navarro Ezquerra, Antonia
Haurie, Laia
Fernández Renna, Ana Inés
Cabeza, Luisa F.
2016-10-03T12:22:49Z
2018-09-01T22:26:07Z
2016
https://doi.org/10.1016/j.enbuild.2016.05.056
024315
0378-7788
http://hdl.handle.net/10459.1/57861
The building sector is one of the highest energy consumers representing around 30% of total energy use. One of the recommendations of the IEA (International Energy Agency) to reduce energy consumption in buildings is to enhance the thermal performance of building envelopes. In the present study, PCM (Phase Change Material) gypsum materials have been manufactured using three different PCM inclusion methods and a thin layer of gypsum without PCM is added as external layer with the aim of improving the fire reaction behaviour. By performing a detailed physical, mechanical and thermal characterization, the suitability of the materials to be implemented in the building envelope as inner coating is demonstrated. Results show that also the thermal properties are improved in the three cases by the addition of PCM. Moreover, the negative effect of adding paraffin wax PCM into gypsum against flame can be easily reduced by the addition of a thin gypsum layer, which is a low tech and cheap solution without extra environmental impact.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd, (c) Elsevier, 2016
Thermal energy storage (TES)
Building coating
PCM gypsum
Material characterization
Fire response
Use of multi-layered PCM gypsums to improve fire response. Physical, thermal and mechanical characterization
article
oai:repositori.udl.cat:10459.1/845172022-12-11T00:05:55Zcom_10459.1_238com_10459.1_2col_10459.1_309
Rosner, Agnes
Basieva, Irina
Barqué Duran, Albert
Glöckner, Andreas
von Helversen, Bettina
Khrennikov, Andrei
Pothos, Emmanuel M.
2022-12-10T18:44:42Z
2022-12-10T18:44:42Z
2022
https://doi.org/10.1016/j.cogpsych.2022.101464
0010-0285
http://hdl.handle.net/10459.1/84517
An intuition of ambivalence in cognition is particularly strong for complex decisions, for which the merits and demerits of different options are roughly equal but hard to compare. We examined information search in an experimental paradigm which tasked participants with an ambivalent question, while monitoring attentional dynamics concerning the information relevant to each option in different Areas of Interest (AOIs). We developed two dynamical models for describing eye tracking curves, for each response separately. The models incorporated a drift mechanism towards the various options, as in standard drift diffusion theory. In addition, they included a mechanism for intrinsic oscillation, which competed with the drift process and undermined eventual stabilization of the dynamics. The two models varied in the range of drift processes postulated. Higher support was observed for the simpler model, which only included drifts from an uncertainty state to either of two certainty states. In addition, model parameters could be weakly related to the eventual decision, complementing our knowledge of the way eye tracking structure relates to decision (notably the gaze cascade effect).
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd (c) Agnes Rosner et. al., 2022.
Ambivalence
Decision making
Eye tracking
Quantum theory
Attention
Gaze cascade
Ambivalence in decision making: An eye tracking study
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/477862021-08-30T15:04:29Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Luque, Rafael
Pineda, Antonio
Colmenares, Juan C.
Campelo, Juan M.
Romero, Antonio A.
Serrano-Ruiz, Juan Carlos
Cabeza, Luisa F.
Cot Gores, Jaume
2015-02-02T10:45:23Z
2012
https://doi.org/10.1016/S1003-9953(11)60360-5
017974
1003-9953
http://hdl.handle.net/10459.1/47786
Tars and alkali ashes from biomass gasification processes currently constitute one of the major problems in biomass valorisation, generating
clogging of filters and issues related with the purity of syngas production. To date, these waste residues find no useful applications and they are
generally disposed upon generation in the gasification process. A detailed analysis of these residues pointed out the presence of high quantities
of Ca (>30 wt%). TG experiments indicated that a treatment under air at moderate temperatures (400−800 ◦C) decomposed the majority
of carbon species, while XRD indicated the presence of a crystalline CaO phase. CaO enriched valorized materials turned out to be good
heterogeneous catalysts for biodiesel production from vegetable oils, providing moderate to good activities (50%−70% after 12 h) to fatty acid
methyl esters in the transesterification of sunflower oil with methanol.
eng
info:eu-repo/semantics/restrictedAccess
(c) Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 2012
(c) Elsevier, 2012
biomass gasification
residues
biodiesel
Carbonaceous residues from biomass gasification as catalysts for biodiesel production
article
oai:repositori.udl.cat:10459.1/478102022-10-17T19:23:57Zcom_10459.1_238com_10459.1_2col_10459.1_309col_10459.1_49291col_10459.1_44504
Oró Prim, Eduard
Miró, Laia
Farid, Mohammed M.
Cabeza, Luisa F.
2015-02-03T08:30:52Z
2020-01-01T23:12:22Z
2012
https://doi.org/10.1016/j.ijrefrig.2012.01.004
017534
0140-7007
http://hdl.handle.net/10459.1/47810
Food transport and storage at low temperatures is a matter worldwide due to changes of the dietary habits and the increasing of the population. The issue of improving food storage applies at different applications such as commercial freezers or refrigerated trucks. The aim of this work is to improve the thermal performance of commercial freezers using phase change materials (PCMs) under door openings and electrical power failure. A commercial PCM was selected (Climsel-18) with a melting temperature of -18 ºC, which is contained in 10 mm thick stainless steel panels placed at different locations in the freezer. During 3 h of electrical power failure, the use of PCM maintained the freezer temperature 4-6 ºC lower and that of the frozen products remains at acceptable levels for much longer time. With frequent door openings the benefit of the PCM is evident when the temperature of the cabinet is near the melting temperature of the PCM.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2012
Cold storage
Commercial application
Freezer
Improving thermal performance of freezers using phase change materials
article
oai:repositori.udl.cat:10459.1/666642022-09-28T20:15:53Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Prieto, Cristina
Cabeza, Luisa F.
2019-08-30T10:56:43Z
2021-08-13T22:06:40Z
2019
https://doi.org/10.1016/j.apenergy.2019.113646
028834
0306-2619
http://hdl.handle.net/10459.1/66664
Concentrated solar power (CSP) is today recognized as a unique renewable energy for electricity generation due to its capability to provide dispatchable electricity incorporating thermal energy storage (TES). Molten salts TES is the most widespread technology in commercial CSP but the industry is looking for cheaper and more efficient TES systems and phase change materials (PCM) have been highlighted as potential low cost and high energy TES systems. This paper presents a completely new concept of PCM energy storage systems to be used in solar thermal electricity plants with its technical assessment. A cascade type PCM storage system is evaluated, using four buckets with the PCM organized based on melting temperature and the latent energy of the materials. Daily, monthly, and annual transient simulations of the plant performance are carried out. The main conclusion is the similarity between this new concept and the commercial two-tank indirect molten salt system. The cumulative power production over the year is similar and the net production of both systems is well matched.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd (c) Elsevier, 2019
Thermal energy storage (TES)
Concentrated solar power (CSP)
Phase change material (PCM)
Cascade system
Transient simulation
Plant performance
Thermal energy storage (TES) with phase change materials (PCM) in solar power plants (CSP). Concept and plant performance
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/477542021-08-30T15:04:35Zcom_10459.1_238com_10459.1_2col_10459.1_309
Castell, Albert
Solé Cutrona, Cristian
Medrano Martorell, Marc
Roca Enrich, Joan
Cabeza, Luisa F.
García, Daniel
2015-01-28T09:37:23Z
2008
https://doi.org/10.1016/j.applthermaleng.2007.11.004
011676
1359-4311
http://hdl.handle.net/10459.1/47754
To determine the heat transfer coefficient by natural convection for specific geometries, experimental correlations are used. No correlations
were found in the literature for the geometries studied in this work. These geometries consisted of a cylindrical module of 88 mm of
diameter and 315 mm height with external vertical fins of 310 mm height and 20 and 40 mm length. To determine the heat transfer coefficient
by natural convection, experimental work was done. This module, containing PCM (sodium acetate trihydrate), was situated in the
middle upper part of a cylindrical water tank of 440 mm of diameter and 450 mm height. The calculated heat transfer coefficient changed
by using external fins, as the heat transfer surface was increased. The temperature variation of the PCM and the water are presented as a
function of time, and the heat transfer coefficient for different fins is presented as a function of the temperature difference. Experimental
correlations were obtained, presenting the Nusselt number as a function of different dimensionless numbers. Different correlations were
analysed to find which one fit better to the experimental data.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2007
Nusselt number
Rayleigh number
Experimental correlation
Natural convection heat transfer coefficients in phase change material (PCM) modules with external vertical fins
article
oai:repositori.udl.cat:10459.1/841342022-12-02T10:08:50Zcom_10459.1_238com_10459.1_2col_10459.1_309
Palacín Roca, Jordi
Rubies, Elena
Clotet Bellmunt, Eduard
2022-11-08T07:52:12Z
2022-11-08T07:52:12Z
2022
https://doi.org/10.3390/s22145262
032822
1424-8220
http://hdl.handle.net/10459.1/84134
The use of electronic noses (eNoses) as analysis tools are growing in popularity; however, the lack of a comprehensive, visual representation of how the different classes are organized and distributed largely complicates the interpretation of the classification results, thus reducing their practicality. The new contributions of this paper are the assessment of the multivariate classification performance of a custom, low-cost eNose composed of 16 single-type (identical) MOX gas sensors for the classification of three volatiles, along with a proposal to improve the visual interpretation of the classification results by means of generating a detailed 2D class-map representation based on the inverse of the orthogonal linear transformation obtained from a PCA and LDA analysis. The results showed that this single-type eNose implementation was able to perform multivariate classification, while the class-map visualization summarized the learned features and how these features may affect the performance of the classification, simplifying the interpretation and understanding of the eNose results.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Jordi Palacín, Elena Rubies, Eduard Clotet, 2022
Electronic nose
eNose
Array of gas sensors
MOX gas sensors
PCA and LDA analysis
Classification of Three Volatiles Using a Single-Type eNose with Detailed Class-Map Visualization
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/657312021-04-21T14:45:55Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Gasia, Jaume
Maldonado, José Miguel
Galati, Francesco
De Simone, Marilena
Cabeza, Luisa F.
2019-02-13T08:25:47Z
2021-02-11T23:26:00Z
2019
https://doi.org/10.1016/j.enconman.2019.01.085
028307
0196-8904
http://hdl.handle.net/10459.1/65731
This paper experimentally studies and compares the addition of fins and the addition of metal wool in a latent heat thermal energy storage (TES) system as heat transfer enhancement techniques. Despite the well-known suitability of fins as enhancement technique, their implementation cost in the TES system is one of its main drawbacks. Therefore, the objective of this study is to evaluate the potential of adding a cheap and commercially available metallic wool in order to overcome the abovementioned drawback. In particular, four different latent heat TES systems based on the shell-and-tube heat exchanger concept were designed using n-octadecane as phase change material (PCM). One of them was used as a reference, while in the remaining configurations the heat transfer surface was increased by means of seventeen rectangular fins and by means of metallic wool arbitrarily distributed within the PCM and compacted in a finned shape. Charging and discharging processes with constant heat transfer fluid temperature and flow rate were evaluated from the temperature and heat transfer points of view. Results were focused on the metal wool because is a cheap and handmade solution which can be implemented in an already made heat exchanger. The addition of metal wool showed an enhancement, during the charge, higher than 10% when it was arbitrarily distributed, while compacting the metal wool in a finned shape showed practically no improvement. During the discharge, both metal wool configurations allowed minimal improvements.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd (c) Elsevier, 2019
Thermal energy storage (TES)
Phase change material (PCM)
Enhancement
Metal wool
Fins
Heat exchanger
Experimental evaluation of the use of fins and metal wool as heat transfer enhancement techniques in a latent heat thermal energy storage system
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/717462023-03-06T14:50:51Zcom_10459.1_238com_10459.1_2col_10459.1_309col_10459.1_49291
Palacín Roca, Jordi
Martínez Piqué, David
2021-08-26T10:40:17Z
2021-08-26T10:40:17Z
2021
https://doi.org/10.3390/s21144763
031600
1424-8220
http://hdl.handle.net/10459.1/71746
This paper proposes a method to improve the angular velocity measured by a low-cost
magnetic rotary encoder attached to a brushed direct current (DC) motor. The low-cost magnetic
rotary encoder used in brushed DC motors use to have a small magnetic ring attached to the rotational
axis and one or more fixed Hall-effect sensors next to the magnet. Then, the Hall-effect sensors
provide digital pulses with a duration and frequency proportional to the angular rotational velocity
of the shaft of the encoder. The drawback of this mass produced rotary encoder is that any structural
misalignment between the rotating magnetic field and the Hall-effect sensors produces asymmetric
pulses that reduces the precision of the estimation of the angular velocity. The hypothesis of this
paper is that the information provided by this low-cost magnetic rotary encoder can be processed
and improved in order to obtain an accurate and precise estimation of the angular rotational velocity.
The methodology proposed has been validated in four compact motorizations obtaining a reduction
in the ripple of the estimation of the angular rotational velocity of: 4.93%, 59.43%, 76.49%, and
86.75%. This improvement has the advantage that it does not add time delays and does not increases
the overall cost of the rotary encoder. These results showed the real dimension of this structural
misalignment problem and the great improvement in precision that can be achieved.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Palacín, J., Martínez, D., 2021
Hall-effect sensor
Low-cost brushed DC motor
Misalignment correction
Improving the Angular Velocity Measured with a Low-Cost Magnetic Rotary Encoder Attached to a Brushed DC Motor by Compensating Magnet and Hall-Effect Sensor Misalignments
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/478162021-08-30T15:04:27Zcom_10459.1_238com_10459.1_2col_10459.1_309col_10459.1_49291col_10459.1_44504
Dutil, Yvan
Rousse, Daniel
Lassue, Stéphane
Zalewski, Laurent
Joulin, Annabelle
Virgone, Joseph
Kuznik, Frédéric
Johannes, Kevyn
Dumas, Jean-Pierre
Bédécarrats, Jean-Pierre
Castell, Albert
Cabeza, Luisa F.
2015-02-03T08:41:35Z
2020-01-01T23:12:22Z
2014
https://doi.org/10.1016/j.renene.2012.10.027
018509
0960-1481
http://hdl.handle.net/10459.1/47816
In a recent meeting of IEA’s Annex 23, several members presented their conclusions on the modeling of
phase change materials behavior in the context of building applications. These conclusions were in
agreement with those of a vast review, involving the survey of more than 250 journal papers, undertaken
earlier by the group of École de technologie supérieure. In brief, it can be stated that, at this point, the
confidence in reviewed models is too low to use them to predict the future behavior of a building with
confidence. Moreover, it was found that overall thermal behaviors of phase change material are poorly
known, which by itself creates an intrinsic unknown in any model. Models themselves are most of time
suspicious as they are often not tested in a very stringent or exhaustive way. In addition, it also appears
that modeling parameters are somewhat too simplified to realistically describe the complete physics
needed to predict the real life performance of PCMs added to a building. As a result, steps are now taken
to create standard model benchmarks that will improve the confidence of the users. Hopefully, following
these efforts, confidence will increase and usage of PCM in buildings should be eased.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2012
Phase change material
PCM characterization
Mathematical model
Modeling phase change materials behavior in building applications: Comments on material characterization and model validation
article
oai:repositori.udl.cat:10459.1/675042021-08-27T14:26:07Zcom_10459.1_238com_10459.1_2col_10459.1_309
Civancik-Uslu, Didem
Puig, Rita
Hauschild, Michael
Fullana i Palmer, Pere
2019-11-08T15:38:31Z
2021-05-28T22:27:50Z
2019-05-28
https://doi.org/10.1016/j.scitotenv.2019.05.372
028617
0048-9697
http://hdl.handle.net/10459.1/67504
Increased plastic consumption has resulted in high amounts of plastic waste ending up in the environment. Recently, the European Commission (EC) has identified a list of single-use plastics, including plastic bags, most commonly found in the European beaches. As a response, alternatives for plastic carrier bags have been more of a concern. Many life cycle assessment (LCA) studies have been performed to evaluate the environmental profile of different carrier bags; however, without considering the possibility of contribution to the littering problem. Therefore, in this study, an indicator has been introduced, based on an LCA study of carrier bags which was performed in Spain. The indicator is influenced by parameters such as: number of bags to fulfill the functional unit, weight, surface, fee, and biodegradability. In this paper, a comparative LCA of HDPE, LDPE, PP, paper and biodegradable plastic bags is presented. Following that, a littering indicator is introduced to allow a comparison of the risk of littering of the different carrier bags in marine environment. The results given by the Littering Potential indicator rank the bags oppositely to the results given by the LCA as usual. Further research is needed to refine the model and include additional contributing variables.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/deed.ca
cc-by-nc-nd (c) Elsevier, 2019
Sustainability
Environmental impacts
Life Cycle Assessment(LCA)
Plastics
Life cycle assessment of carrier bags and development of a littering indicator
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/478262021-08-30T14:56:38Zcom_10459.1_238com_10459.1_2col_10459.1_309col_10459.1_49291
Oró Prim, Eduard
Castell, Albert
Chiu, Justin
Martin, Viktoria
Cabeza, Luisa F.
2015-02-03T10:16:35Z
2013
https://doi.org/10.1016/j.apenergy.2012.12.082
018988
0306-2619
http://hdl.handle.net/10459.1/47826
District cooling and heating networks are increasing in many countries, especially in the Scandinavian
countries. Some of the systems have become small for the needs of the population and they have to be
enhanced in order to reach the cooling or heating necessities. Here, thermal energy storage system of
a district cooling network is studied. Phase change material (PCM) is used in order to enhance the energy
density and the stratification of the water tank. The experimental set up consists mainly of a cylindrical
storage tank with a capacity of 3.73 L filled with spherically encapsulated PCM. The PCM used is PK6 from
Rubitherm GmbH with a storage capacity of 175 kJ/kg between 2 C and 13 C. Many methods to characterize
water tank stratification, such as graphical (dimensional and non-dimensional) and numerical
figures based on temperature distribution (degree of stratification, first law efficiencies, second law efficiencies,
other efficiencies as MIX number), are used to analysed and characterized two storage tanks, one
of them with the inclusion of PCM packed bed during both charging and discharging processes.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2013
District cooling
Thermal energy storage
Phase change material
Stratification analysis in packed bed thermal energy storage systems
article
oai:repositori.udl.cat:10459.1/715142021-06-30T00:11:05Zcom_10459.1_238com_10459.1_2col_10459.1_309
Alcaraz Martínez, Rubén
Ribera Turró, Mireia
2021-06-29T08:20:16Z
2021-06-29T08:20:16Z
2020
https://doi.org/10.3145/epi.2020.sep.14
1699-2407
http://hdl.handle.net/10459.1/71514
During the Covid-19 pandemic, people rely on the Internet in order to obtain information that can help them understand
the coronavirus crisis. This situation has exposed the need to ensure that everyone has access to essential information
on equal terms. During this situation, statistical charts have been used to display data related to the pandemic, and have
had an important role in conveying, clarifying and simplifying information provided by governments and health organisations.
Scientific literature and the guidelines published by organizations have focused on proposing solutions to make
charts accessible for blind people or people with very little visual rest. However, the same efforts are not made towards
people with low vision, despite their higher prevalence in the population of users with visual impairment. This paper
reviews the accessibility of the statistical charts about the Covid-19 crisis for people with low vision that were published
by the Brazilian, British, Russian, Spanish, European Union, and the United States’ governments and also by the World
Health Organization and Johns Hopkins University, relating to the countries most severely affected by the pandemic. The
review is based on specific heuristic indicators, with a mixed quantitative and qualitative approach. Overall, the reviewed
charts offer a reasonable level of accessibility, although there are some relevant problems affecting many of the low vision
profiles that remain to be solved. The main problems identified are: poor text alternatives in both, raster images and
SVG charts; the incompatibility with a keyboard interface; insufficient non-text contrast against adjacent colours (in chart
elements such as bars, lines or areas), no customization options; and the lack of an optimized print version for users for
whom reading on screen is challenging.
eng
info:eu-repo/semantics/openAccess
(c) EPI SCP, 2020
Covid-19
SARS-CoV-2
2019-nCoV
Coronavirus
Pandemics
Statistical charts
Information visualization
Low vision
Colour vision deficiency
Colour blindness
Web accessibility
Health information
Heuristic evaluation
An evaluation of accessibility of Covid-19 statistical charts of governments and health organisations for people with low vision
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/711642021-04-28T00:20:29Zcom_10459.1_238com_10459.1_2com_10459.1_239col_10459.1_309col_10459.1_10984
Amils, Ricardo
Rodríguez Garrido, Nuria
Lalueza Baró, Joana
Rius Carrasco, Antoni
Ollé i Otero, Lluís
Puig, Rita
Font Vallès, Joaquim
2021-04-27T10:40:38Z
2021-04-27T10:40:38Z
2006
028362
0365-5873
http://hdl.handle.net/10459.1/71164
Hoy por hoy las aguas residuales de los procesos de curtición, donde el cromo se encuentra presente
en cantidades significativas, pueden tratarse por métodos fisico-químicos y la eliminación de
este metal es considerable. Existen otras etapas, posteriores a la curtición propiamente dicha, donde el cromo
se encuentra en cantidades importantes pero donde no es posible aplicar el método fisico-químico de eliminación
y sin embargo generan efluentes con un conlenido en cromo considerable. Como consecuencia, en las
depuradoras donde se tratan, se obtienen fangos con elevado contenido de este metal cosa que comporta su
destino a vertederos especiales. Es evidente pues que en este caso el disponer de una tecnología para eliminar el
cromo de dichas aguas residuales sería de gran interés.
spa
info:eu-repo/semantics/openAccess
(c) AQEIC, 2006
Aguas residuales
Cromo(III)
Biotecnología
Hongos acidófilos
Procedimiento biotecnológico para la recuperación de Cr(III) de los efluentes de curtición
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/707232022-10-04T15:33:54Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Carbajo Garcia, Ruth
Cabeza, Luisa F.
2021-03-11T07:56:52Z
2021
https://doi.org/10.1016/j.rser.2021.110936
031096
1364-0321
http://hdl.handle.net/10459.1/70723
The enhancement and the understanding of the societal dynamics in the energy systems within transition entails the inclusion of innovative policy and research strategies. This inclusion raises several questions that change profoundly the nature of the research and innovation endeavour, questions that have not been sufficiently explored in the literature. These questions are, among others, the complexities an scope of socio-technical integration or the emergence of new roles and patterns such as user-inspired innovations or community innovations. Based on the assumptions of the responsible-based approaches advocating to energy system actors to collaborate sharing responsibility and the benefits that perspectives integration brings in the development of proactive and archivable energy and climate policies, this study analyses a group of researchers within the field of thermal energy storage (TES) for renewable energy applications, for the purpose of evaluating their perception regarding to the inclusion of alternative policy proposals and collaborative research strategies. The proposed methodology was based on the use of the common theoretical backgrounds of socio-technical transition for the construction of an responsibility-based approach and the proposal of a survey tool for gathering the empirical evidence from researchers opinions. The survey data was collected from a representative group of researchers (33 countries, 215 targeted researches completing the surveys at 31% with a final N = 72). Findings shows willingness to include citizens as beneficiaries but not as participants of research decisions, the prevalence of the use of social sciences to increase the acceptance of technology and remarkable unawareness regarding collaborative research strategies. This paper brings an important contribution for the selected researchers that can be extrapolate to other energy communities since illuminates the possibility of adapting and asses TES to include new patterns and new governance strategies based in RRI.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Ruth Carbajo, Luisa F. Cabeza, 2021
Researcher acceptance
Responsible research and innovation (RRI)
Thermal energy storage (TES)
Socio-technical transition
Collaborative research strategies
Researchers perception regarding socio-technical approaches implementation in their own research. Thermal energy storage researchers as example
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/478192022-10-14T20:25:11Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Gracia Cuesta, Alvaro de
David, Damien
Castell, Albert
Cabeza, Luisa F.
Virgone, Joseph
2015-02-03T08:45:52Z
2013
https://doi.org/10.1016/j.applthermaleng.2012.11.045
018610
1359-4311
http://hdl.handle.net/10459.1/47819
This paper provides a new correlation to determine the heat transfer coefficient between an air flow and
a plate made of phase change material (PCM). This correlation was built for the simulation of heat storage
units containing PCM plates subjected to an inlet temperature step. The presented correlation has the
following form: NuPCM
x;t ¼ NuPSM$f PCM. The first term NuPSM is for a plate made of traditional material. The
term fPCM is a perturbation due to the phase change in the plate. Each term depends on 5 non-dimensional
parameters. One of them represents the advance in the total heating or cooling process, in order to
take into account the transient evolution of the convective coefficient. The correlations are built using the
Least Squares Method, from series of CDF simulation data. The shape of the perturbation fPCM reveals
a complex evolution of the temperature repartition in the PCM plate. Finally, a nodal model of the plate
has been developed in order to test the provided new correlation and other correlations available in the
literature. The results obtained with the present correlation show better agreements with the CFD
results, which make this correlation suitable for the simulation of PCM heat storage systems.
eng
info:eu-repo/semantics/openAccess
(c) Elsevier, 2012
Convective heat transfer coefficient
Correlation
Phase change material
A correlation of the convective heat transfer coefficient between an air flow and a phase change material plate
article
oai:repositori.udl.cat:10459.1/648642020-02-28T13:21:08Zcom_10459.1_238com_10459.1_2col_10459.1_309
Tresánchez Ribes, Marcel
Pujol, Alain
Pallejà Cabrè, Tomàs
Martínez Lacasa, Daniel
Clotet Bellmunt, Eduard
Palacín Roca, Jordi
2018-10-11T08:34:18Z
2018-10-11T08:34:18Z
2018
https://doi.org/10.1016/j.procs.2018.07.149
027961
1877-0509
http://hdl.handle.net/10459.1/64864
This paper proposes the design of a low-cost, low-power and small size image acquisition device to be used in Internet of Things (IoT) applications which collects, processes and sends image data through a 2.4GHz Wi-Fi connection. The proposed processing unit is a low-cost high-performance STM32F7 microcontroller which is able to acquire and transfer images at full rate keeping the core idle to do image processing. The device is supported by a 1.3 Megapixel CMOS camera sensor, and a low consumption Wi-Fi module. This setup allows to create a very compact image sensor device with a built-in processing algorithm for a specific functionality in IoT. In this work, the device hardware architecture is described and discussed, and a comparison with alternative hardware solutions are presented.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd (c) Marcel Tresánchez et al., 2018
Image sensor
Video streaming
ARM
IoT sensor node
A proposal of low-cost and low-power embedded wireless image sensor node for IoT applications
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/572792021-08-30T15:04:35Zcom_10459.1_238com_10459.1_2col_10459.1_309
Martorell, Ingrid
Herrero, Joan
Grau, Francesc X.
2016-06-23T09:43:43Z
2003
https://doi.org/10.1016/S0017-9310(03)00010-3
007301
0017-9310
http://hdl.handle.net/10459.1/57279
The present work deals with the natural convection flow and heat transfer from a horizontal plate cooled from
above.Experiments are carried out for rectangular plates having aspect ratios between / ¼ 0:036 and 0.43 and Rayleigh
numbers in the range 2906Raw 63:3 105.These values of Raw and / have been selected below those commonly
considered in previous research in view of a future application to the design of printed circuit boards.The plates are
made of two different metals, copper and steel.The choice of a metal is relevant to the present problem because the
plates are heated by means of an electric current.Important variations of the surface temperature are observed along
the transverse direction for the steel plates.The surface of the copper plates is almost isothermal because of the high
thermal conductivity of the metal.
Calculations for a semi-infinite plate are carried out to predict the transverse profiles of the surface temperature and
heat flux and to visualize the structure of the flow.Three-dimensional calculations are also used at a qualitative level to
observe the changes in the flow structure due to the finite length of the plate.Present results are compared with both
previous experimental work and analyses that are based on boundary layer theory.It is shown that analyses for an
infinite boundary layer are not completely applicable to the present problem because of its different physics.The most
relevant feature of the natural convection flow, which is not predicted by boundary layer analyses, is a thermal plume
rising near the center of the plate.
Present heat transfer results differ from previous experimental work because of the lower Rayleigh numbers and
aspect ratios investigated here.The Nusselt number is found to depend on Ran
w, with the exponent n ¼ 0:17 being lower
than most of the values reported in the literature.This comparatively low value is related to the transverse conduction
of heat through the air, which becomes increasingly significant as Raw approaches zero.It is shown that such a low-Raw
effect can be accounted for in a physically consistent manner by adding a constant term to the heat transfer correlation.
On the other hand, it is found that the Nusselt number does not significantly depend on the aspect ratio in the range of
/ investigated contrary to what has been previously reported for wider plates.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2003
Heat transfer
Natural convection
Plate
Natural convection from narrow horizontal plates at moderate Rayleigh numbers
article
oai:repositori.udl.cat:10459.1/572632021-08-30T14:56:38Zcom_10459.1_238com_10459.1_2col_10459.1_309col_10459.1_49291
Noguera, Carles
Esteva, Francesc
Gispert, Joan
2016-06-22T11:24:58Z
2008
https://doi.org/10.1002/malq.200710054
012406
0942-5616
http://hdl.handle.net/10459.1/57263
In this paper we carry out an algebraic investigation of the weak nilpotent minimum logic (WNM) and its t-norm based axiomatic extensions. We consider the algebraic counterpart of WNM, the variety of WNM-algebras ([MATHEMATICAL DOUBLE-STRUCK CAPITAL W]ℕ[MATHEMATICAL DOUBLE-STRUCK CAPITAL M]) and prove that it is locally finite, so all its subvarieties are generated by finite chains. We give criteria to compare varieties generated by finite families of WNM-chains, in particular varieties generated by standard WNM-chains, or equivalently t-norm based axiomatic extensions of WNM, and we study their standard completeness properties. We also characterize the generic WNM-chains, i. e. those that generate the variety [MATHEMATICAL DOUBLE-STRUCK CAPITAL W]ℕ[MATHEMATICAL DOUBLE-STRUCK CAPITAL M], and we give finite axiomatizations for some t-norm based extensions of WNM.
eng
info:eu-repo/semantics/restrictedAccess
(c) WILEY-VCH Verlag, 2008
Algebraic logic
Fuzzy logic
Left-continuous t-norm
Mathematical fuzzy logic
On triangular norm based axiomatic extensions of the weak nilpotent minimum logic
article
oai:repositori.udl.cat:10459.1/845092022-12-10T00:06:13Zcom_10459.1_238com_10459.1_2col_10459.1_309
Bitriá, Ricard
Palacín Roca, Jordi
2022-12-09T12:59:58Z
2022-12-09T12:59:58Z
2022
https://doi.org/10.3390/s22207817
032825
1424-8220
http://hdl.handle.net/10459.1/84509
The development of a proportional–integral–derivative (PID) control system is a simple,
practical, highly effective method used to control the angular rotational velocity of electric motors.
This paper describes the optimization of the PID control of a brushed DC motor (BDCM) with an
embedded low-cost magnetic quadrature encoder. This paper demonstrates empirically that the
feedback provided by low-cost magnetic encoders produces some inaccuracies and control artifacts
that are not usually considered in simulations, proposing a practical optimization approach in order
to improve the step overshoot and undershoot controller response. This optimization approach is
responsible for the motion performances of a human-sized omnidirectional mobile robot using three
motorized omnidirectional wheels.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Ricard Bitriá, Jordi Palacín, 2022
PID control
Brushed DC motor
Magnetic encoder
Omnidirectional mobile robot
Optimal PID Control of a Brushed DC Motor with an Embedded Low-Cost Magnetic Quadrature Encoder for Improved Step Overshoot and Undershoot Responses in a Mobile Robot Application
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/585822019-02-01T09:52:49Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291col_10459.1_44504
Gasia, Jaume
Tay, N. H. Steven
Belusko, Martin
Cabeza, Luisa F.
Bruno, Frank
2016-11-18T13:08:56Z
2019-01-01T23:29:27Z
2017
https://doi.org/10.1016/j.apenergy.2016.10.042
024917
0306-2619
http://hdl.handle.net/10459.1/58582
In the present paper, an experimental study is carried out to evaluate the effect of the dynamic melting concept in a cylindrical shell-and-tube heat exchanger using water as the phase change material (PCM) and a potassium formate/water solution as the heat transfer fluid (HTF). The dynamic melting concept is a new heat transfer enhancement technique which consists of recirculating the liquid PCM during the melting process with a pump and thus increasing the overall heat transfer coefficient as a result of the dominance of the forced convection. The HTF flow rate was kept constant at 1 l/min and four different PCM flow rates of 0, 0.5, 1 and 2 l/min were tested. Results from the experimental analysis showed enhancements up to 65.3% on the melting period, up to 56.4% on the effectiveness, and 66% on the heat transfer rates when the PCM flow rate was twice the HTF flow rate. From these experiments, it can be concluded that dynamic melting is an effective technique for enhancing heat transfer during melting of PCM.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd, (c) Elsevier, 2017
Thermal energy storage
Phase change material
Dynamic melting
Heat transfer enhancement
Effectiveness
Experimental investigation of the effect of dynamic melting in a cylindrical shell-and-tube heat exchanger using water as PCM
article
oai:repositori.udl.cat:10459.1/837442022-09-02T00:07:49Zcom_10459.1_238com_10459.1_2col_10459.1_309
Palacín Roca, Jordi
Clotet Bellmunt, Eduard
Rubies, Elena
2022-09-01T08:44:44Z
2022-09-01T08:44:44Z
2022
https://doi.org/10.3390/chemosensors10030118
032179
2227-9040
http://hdl.handle.net/10459.1/83744
This paper assesses the over time performance of a custom electronic nose (eNose) composed of an array of commercial low-cost and single-type miniature metal-oxide (MOX) semiconductor gas sensors. The eNose uses 16 BME680 versatile sensor devices, each including an embedded
non-selective MOX gas sensor that was originally proposed to measure the total volatile organic
compounds (TVOC) in the air. This custom eNose has been used previously to detect ethanol and
acetone, obtaining initial promising classification results that worsened over time because of sensor
drift. The current paper assesses the over time performance of different classification methods applied
to process the information gathered from the eNose. The best classification results have been obtained
when applying a linear discriminant analysis (LDA) to the normalized conductance of the sensing
layer of the 16 MOX gas sensors available in the eNose. The LDA procedure by itself has reduced the
influence of drift in the classification performance of this single-type eNose during an evaluation
period of three months
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Jordi Palacín, Eduard Clotet, Elena Rubies, 2022
Electronic nose
Array of MOX gas sensors
Linear discriminant analysis
LDA
Assessing over Time Performance of an eNose Composed of 16 Single-Type MOX Gas Sensors Applied to Classify Two Volatiles
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/479002022-10-19T19:51:54Zcom_10459.1_238com_10459.1_2col_10459.1_309col_10459.1_49291
Moreno Argilés, Pere
Miró, Laia
Barreneche Güerisoli, Camila
Solé Cutrona, Cristian
Martorell, Ingrid
Cabeza, Luisa F.
2015-02-09T11:14:42Z
2014
https://doi.org/10.1016/j.apenergy.2014.03.022
020812
0306-2619
http://hdl.handle.net/10459.1/47900
Thermal energy storage (TES) using phase change materials (PCM) can be used for load shaving or peak
load shifting when coupled to a heating, ventilation, and air-conditioning (HVAC) system such as heat
pump. In these systems the PCM is embedded in packages or used in bulk, so the compatibility of the
encapsulation materials and the PCM is a key factor to ensure long operational life of the system.
Although corrosion caused by salts is known from the chemical industry, when these salts are used as
PCM no corrosion data is available, since the salts are used without being in water solution. Producing
new corrosion data is essential for PCM utilisation in new applications. In this study the corrosion rate
of two metals and two metal alloys when they are in contact with different salt hydrate PCM is evaluated;
in total eleven PCM, being four of them commercial PCM, are tested. Since they are PCM to be used for
heating and cooling applications they are classified in two different groups to present the corrosion study.
Results present the recommendation of using each PCM with the different metals and metal alloys
according to the obtained corrosion rate and visual observation of the samples.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2014
Thermal energy storage
Phase change materials
HVAC
Corrosion of metal and metal alloy containers in contact with phase change materials (PCM) for potential heating and cooling applications
article
oai:repositori.udl.cat:10459.1/576202021-08-30T14:56:40Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56946
Palacín Roca, Jordi
Salse, José Antonio
Valgañón, Ignasi
Clua, Xavier
2016-07-13T12:29:47Z
2004
https://doi.org/10.1109/TIM.2004.834093
001945
0018-9456
http://hdl.handle.net/10459.1/57620
Domestic robots are one of the new industrial challenges.
In this paper, a floor-cleaning robot specifically designed
for this function is proposed. Aspects such as sensor placement,
motor control, robot control, and safety are considered toward an
optimal implementation of this helpful robot.
eng
info:eu-repo/semantics/restrictedAccess
(c) Institute of Electrical and Electronics Engineers, 2004
Acoustic applications
Acoustic devices
Mobile robot motion-planning
Building a Mobile Robot for a Floor-Cleaning Operation in Domestic Environments
article
oai:repositori.udl.cat:10459.1/648882023-01-12T07:32:54Zcom_10459.1_238com_10459.1_2col_10459.1_309col_10459.1_49291
Albertos Marco, Félix
Penichet, Victor M. R.
Gallud, Jose A.
2018-10-16T14:06:05Z
2018-10-16T14:06:05Z
2013-04-01
https://doi.org/10.3217/jucs-019-07-0894
027453
0948-695X
http://hdl.handle.net/10459.1/64888
E-Learning platforms allow users to collaborate with one other. Moodle, as one of the main e-Learning platforms, provides tools to perform collaborative tasks. With these tasks, students are able to share documents and information. The means provided by Moodle are not enough to perform some collaborative tasks, such as sharing documents in real-time. In this scenario users must be aware of what is happening in the system effectively. We propose the use of Drag & Share within Moodle, a collaborative tool that allows users to synchronously share resources in real-time. Through this tool, teachers are able to easily provide a shared workspace for students and be able to create groups. With such a tool, students can share all kind of resources and be aware of what is going on in the system in which they are participating and of what they are doing. All these features use standard technologies, such as HTML5.
eng
info:eu-repo/semantics/openAccess
(c) IICM (Institute f.Information Processing and Computer Supported Media), 2013
Collaboration
Real Time
Awareness
Shared Workspaces
eLearning
Moodle
HTML5
Collaborative e-learning through drag & share in synchronous shared workspaces
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/571992018-02-05T14:04:08Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291col_10459.1_44504
Gasia, Jaume
Gutiérrez, Andrea
Peiró Bell-lloch, Gerard
Miró, Laia
Grágeda, Mario
Ushak, Svetlana
Cabeza, Luisa F.
2016-06-14T11:01:32Z
2017-10-01T22:25:57Z
2015
https://doi.org/10.1016/j.apenergy.2015.06.042
022993
0306-2619
http://hdl.handle.net/10459.1/57199
The selection of the proper thermal energy storage (TES) material for an application is crucial. On the one
hand, these materials should have suitable thermal properties for the operational temperatures range of
the systems they are planned to work for, such as thermal stability, high latent heat and high heat capacity.
On the other hand, they should be available on the market and at low price. Besides, researchers have
to bear in mind the importance of testing TES materials not only at laboratory scale but also at higher
scale, since it has been demonstrated that some thermal characteristics are volume-dependant. In the
present study, bischofite, a by-product obtained from the non-metallic industry in the North of Chile with
desired thermal properties for mid-temperature applications (around 100 C), has been studied. A first
analysis was performed in terms of comparing the thermal properties and cost of bischofite with other
material previously studied as TES materials in order to evaluate its potential in both latent and sensible
phases. Afterwards, a second analysis was experimentally performed in terms of testing bischofite at
large-scale (204 kg) in a pilot plant facility. The experimental procedure consisted on several charging
processes within two different temperatures ranges: from 50 C to 80 C and from 80 C to 120 C in order
to study the behavior of the material in the sensible solid phase and latent phase respectively. The temperature
profiles, the power given by the HTF, the energy balance in the storage system and the accumulation
energy rate of the bischofite were analyzed. Results of both analysis showed that bischofite has
potential as TES material for mid-temperature applications.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd, (c) Elsevier, 2015
Bischofite
By-product
Phase change materials (PCM)
Thermal energy storage (TES)
Thermal performance evaluation of bischofite at pilot plant scale
article
oai:repositori.udl.cat:10459.1/723502022-01-11T12:42:34Zcom_10459.1_238com_10459.1_2col_10459.1_309
Palacín Roca, Jordi
Rubies, Elena
Clotet Bellmunt, Eduard
Martínez Piqué, David
2021-11-18T08:54:22Z
2021-11-18T08:54:22Z
2021
https://doi.org/10.3390/s21217216
031842
1424-8220
http://hdl.handle.net/10459.1/72350
This paper presents the empirical evaluation of the path-tracking accuracy of a three-wheeled omnidirectional mobile robot that is able to move in any direction while simultaneously changing its orientation. The mobile robot assessed in this paper includes a precise onboard LIDAR for obstacle avoidance, self-location and map creation, path-planning and path-tracking. This mobile robot has been used to develop several assistive services, but the accuracy of its path-tracking system has not been specifically evaluated until now. To this end, this paper describes the kinematics and path-planning procedure implemented in the mobile robot and empirically evaluates the accuracy of its path-tracking system that corrects the trajectory. In this paper, the information gathered by the LIDAR is registered to obtain the ground truth trajectory of the mobile robot in order to estimate the path-tracking accuracy of each experiment conducted. Circular and eight-shaped trajectories were assessed with different translational velocities. In general, the accuracy obtained in circular trajectories is within a short range, but the accuracy obtained in eight-shaped trajectories worsens as the velocity increases. In the case of the mobile robot moving at its nominal translational velocity, 0.3 m/s, the root mean square (RMS) displacement error was 0.032 m for the circular trajectory and 0.039 m for the eight-shaped trajectory; the absolute maximum displacement errors were 0.077 m and 0.088 m, with RMS errors in the angular orientation of 6.27° and 7.76°, respectively. Moreover, the external visual perception generated by these error levels is that the trajectory of the mobile robot is smooth, with a constant velocity and without perceiving trajectory corrections.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Palacín et al., 2021
Omnidirectional mobile robot
Path tracking
Kinematic model
Inverse kinematic model
Evaluation of the Path-Tracking Accuracy of a Three-Wheeled Omnidirectional Mobile Robot Designed as a Personal Assistant
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/837432022-09-02T00:07:41Zcom_10459.1_238com_10459.1_2col_10459.1_309
Palacín Roca, Jordi
Rubies, Elena
Clotet Bellmunt, Eduard
2022-09-01T08:33:28Z
2022-09-01T08:33:28Z
2022
https://doi.org/10.3390/app12052606
032178
2076-3417
http://hdl.handle.net/10459.1/83743
Odometry is a simple and practical method that provides a periodic real-time estimation of
the relative displacement of a mobile robot based on the measurement of the angular rotational speed
of its wheels. The main disadvantage of odometry is its unbounded accumulation of errors, a factor
that reduces the accuracy of the estimation of the absolute position and orientation of a mobile robot.
This paper proposes a general procedure to evaluate and correct the systematic odometry errors of a
human-sized three-wheeled omnidirectional mobile robot designed as a versatile personal assistant
tool. The correction procedure is based on the definition of 36 individual calibration trajectories
which together depict a flower-shaped figure, on the measurement of the odometry and ground
truth trajectory of each calibration trajectory, and on the application of several strategies to iteratively
adjust the effective value of the kinematic parameters of the mobile robot in order to match the
estimated final position from these two trajectories. The results have shown an average improvement
of 82.14% in the estimation of the final position and orientation of the mobile robot. Therefore, these
results can be used for odometry calibration during the manufacturing of human-sized three-wheeled
omnidirectional mobile robots.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Jordi Palacín, Elena Rubies, Eduard Clotet, 2022
Odometry
Odometry calibration
Omnidirectional mobile robot
Systematic Odometry Error Evaluation and Correction in a Human-Sized Three-Wheeled Omnidirectional Mobile Robot Using Flower-Shaped Calibration Trajectories
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/712282021-12-21T00:22:53Zcom_10459.1_238com_10459.1_2com_10459.1_72344col_10459.1_309col_10459.1_72345
Ollé i Otero, Lluís
Frías Álvarez, Aroha
Sorolla, Sílvia
Cuadros Domènech, Rosa
Bacardit i Dalmases, Anna
2021-05-05T11:41:03Z
2021-02-16
https://doi.org/10.1016/j.porgcoat.2021.106162
031032
0300-9440
http://hdl.handle.net/10459.1/71228
The leather industry needs innovative products to meet the continued demands of the global market. To achieve a good performance in the finishing operation, crosslinking of the polymers used in this leather production stage is necessary. These crosslinkers are irritating and harmful.
This study is based on the synthesis of functionalized acryl polymers with epoxy groups to improve the properties of the leather finishing to avoid the use of external crosslinkers, and consequently; harmful products for health and the environment will not be necessary.
Likewise, the affectation in the health of workers exposed to crosslinker has been investigated when the leather finish is carried out. To do this research, a clinical analysis has been carried out prior authorization of the workers.
The study demonstrates a good performance finishing avoiding the use of crosslinkers. In addition, it has been determined that molecular fragments of the decomposition of polyaziridine are present in the urine of one of the employees. Although the human metabolism may metabolize these polyaziridine fragments being non detectable in the urine samples, a positive result was obtained in the analysis by GC-MSD of the urine, and therefore; it could affect the health of this employee.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Ollé et al., 2021
Human health
Polyaziridine
Leather finishing
Crosslinkers
Self-crosslinking
Study of the impact on occupational health of the use of polyaziridine in leather finishing compared with a new epoxy acrylic self-crosslinking polymer
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/4645842024-03-21T09:13:45Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291col_10459.1_44504
Rehman, Omais Abdur
Palomba, Valeria
Vérez, David
Borri, Emiliano
Frazzica, Andrea
Brancato, Vincenza
Botargues, Teresa
Ure, Zafer
Cabeza, Luisa F.
2023-11-22T07:43:14Z
2023-11-22T07:43:14Z
2023
https://doi.org/10.1016/j.est.2023.109359
033648
2352-152X
https://repositori.udl.cat/handle/10459.1/464584
Extensive research has been conducted on utilizing phase change materials for cooling applications, making it one of the most explored techniques in this domain. This research paper presents a comprehensive performance evaluation of a latent heat thermal energy storage unit featuring three distinct macro-encapsulation designs for phase change materials. The study aims to assess the thermal performance, efficiency, and practical applicability of these macro-encapsulation designs in a storage system. The PCM macro-encapsulation designs under investigation include cylindrical and rectangular shapes, each possessing different geometry. Two different configurations have been considered in this study. One configuration contains same PCM mass in order to have similar storage capacity while the other configuration has maximum PCM mass that can be inserted inside the tank. The used phase change material is a salt hydrate with melting temperature of 17 °C. The experimental setup consists of a controlled test rig that simulates real-world conditions and enables the comparative analysis of the three designs. Key performance parameters such as the charging and discharging time, temperature profiles, heat transfer rate, and energy storage/retrieval rates are measured and analysed. The results obtained from the experimental study provide valuable insights into the thermal behaviour, energy storage capacity, and overall effectiveness of the three macro-encapsulation designs. It is important to mention that use of an encapsulation design is highly dependent on application. The findings of this study contribute to the understanding of the impact of different macro-encapsulation designs on performance of thermal energy storage units. The results serve as a basis for optimizing macro-encapsulation designs, improving the efficiency and reliability of latent heat storage systems, and promoting their wider adoption in various energy management applications.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd (c) The Authors, 2023
Thermal energy storage
Macro-encapsulation designs
Phase change material (PCM)
Experimental study
Cooling applications
Experimental evaluation of different macro-encapsulation designs for PCM storages for cooling applications
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/853942023-02-10T00:07:45Zcom_10459.1_238com_10459.1_2col_10459.1_309col_10459.1_49291
Álvarez‑Carulla, Albert
Saiz Vela, Albert
Puig‑Vidal, Manel
López‑Sánchez, Jaime
Colomer‑Farrarons, Jordi
Miribel‑Català, Pere Ll.
2023-02-09T13:39:46Z
2023-02-09T13:39:46Z
2023
https://doi.org/10.1038/s41598-023-28378-6
2045-2322
http://hdl.handle.net/10459.1/85394
In recent years, research on transducers and system architectures for self-powered devices has gained attention for their direct impact on the Internet of Things in terms of cost, power consumption, and environmental impact. The concept of a wireless sensor node that uses a single thermoelectric generator as a power source and as a temperature gradient sensor in an efficient and controlled manner is investigated. The purpose of the device is to collect temperature gradient data in data centres to enable the application of thermal-aware server load management algorithms. By using a maximum power point tracking algorithm, the operating point of the thermoelectric generator is kept under control while using its power-temperature transfer function to measure the temperature gradient. In this way, a more accurate measurement of the temperature gradient is achieved while harvesting energy with maximum efficiency. The results show the operation of the system through its different phases as well as demonstrate its ability to efficiently harvest energy from a temperature gradient while measuring it. With this system architecture, temperature gradients can be measured with a maximum error of 0.14 ∘
C and an efficiency of over 92% for values above 13 ∘
C and a single transducer.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Albert Álvarez-Carulla et al., 2023
Electrical and electronic engineering
Energy harvesting
Energy infrastructure
Thermoelectric devices and materials
High-efficient energy harvesting architecture for self-powered thermal-monitoring wireless sensor node based on a single thermoelectric generator
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/583982022-01-27T11:00:22Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291col_10459.1_44504
Ushak, Svetlana
Marín, Paula E.
Galazutdinova, Yana
Cabeza, Luisa F.
Farid, Mohammed M.
Grágeda, Mario
2016-11-07T09:37:37Z
2018-08-25T22:28:36Z
2016
https://doi.org/10.1016/j.applthermaleng.2016.06.171
024727
1359-4311
http://hdl.handle.net/10459.1/58398
The potential of the use of salt hydrates MgCl2·6H2O (bischofite) with typical impurities of the Salar de Atacama as a thermal energy storage material was evaluated with special attention to its corrosion behavior. Bischofite behavior is compared with that of commercial salt MgCl2·6H2O. The corrosion tests were conducted with metal sheets (copper, aluminum and stainless steel) partially immersed in molten salt hydrates at a temperature of 120 °C during 1500 h. The results showed minimum corrosion on all the immersed surfaces of all the metals. However, very sever corrosion was observed at the salt/air interface due to a known phenomenon of oxygen enhanced corrosion usually found even with water at ambient temperature. The corrosion products were determined with scanning electron microscopy (SEM-EDX) and X-ray diffraction (XRD) technique. For salts hydrates bischofite and MgCl2·6H2O, the results show the formation of cuprite (Cu2O) and hematite (Fe2O3) on copper and stainless steel samples, respectively. For all cases studied in the present work, several chloride compounds were identified as corrosion products.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd, (c) Elsevier, 2016
Phase change materials
Salt hydrates
Interface corrosion
Bischofite
Compatibility of materials for macroencapsulation of inorganic phase change materials: experimental corrosion study
article
oai:repositori.udl.cat:10459.1/696782023-09-13T13:28:31Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Cabeza, Luisa F.
Frazzica, Andrea
Chàfer, Marta
Vérez, David
Palomba, Valeria
2020-10-21T06:29:28Z
2022-10-17T22:12:12Z
2020
https://doi.org/10.1016/j.est.2020.101976
030546
2352-152X
http://hdl.handle.net/10459.1/69678
The development of renewable energy sources (RES) to achieve the UN Sustainable Development Goals of a 100% RES-based energy system has driven a lot of research on batteries for electric vehicles and stationary applications, to further support the RES penetration. Batteries are strongly linked to the thermal conditions at which they operate, therefore the study and adequate implementation of a correct thermal management of batteries is essential for their better deployment and use. But this is a relatively new research topic with growing interest in recent years. This paper presents a bibliometric analysis of battery thermal management systems to understand the trends, assess the state-of-the-art, and identify research gaps. Results show that most research is carried out in lithium-ion batteries, and that the thermal managements systems studied are air cooling, liquid cooling, and phase change materials as passive systems or in combination with air and liquid cooling ones. The biggest research gaps are the lack of studies on other battery types and a clear comparison among these kinds of thermal management systems.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd (c) Elsevier, 2020
Bibliometric analysis
Research trends
Literature gaps
Electric batteries
Thermal management
Research trends and perspectives of thermal management of electric batteries: Bibliometric analysis
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/478132021-08-30T15:04:27Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291col_10459.1_44504
Menoufi, Karim Ali Ibrahim
Castell, Albert
Farid, Mohammed M.
Boer, Dieter
Cabeza, Luisa F.
2015-02-03T08:38:35Z
2020-01-01T23:12:22Z
2013
https://doi.org/10.1016/j.renene.2012.10.010
018316
0960-1481
http://hdl.handle.net/10459.1/47813
Among the research activities that aim at reducing energy consumption in buildings and their impact on
the environment is an experimental set-up that has several house-shaped cubicles constructed in
Puigverd de Lleida (Spain). Assessing the environmental impact through studying the manufacturing,
operational and disposal phases of these cubicles have been done in previous research. The objective of
this paper is to investigate the use of esters as PCM in order to estimate its environmental impact in
building envelopes in comparison to the use of paraffin or salt hydrates through a theoretical study. The
evaluation of the environmental impact of this type of PCM material is conducted using Life Cycle
Assessment (LCA) based on the Eco-indicator 99 method. It is found that the impact of ester used as PCM
presents slightly better results than the case of using salt hydrates during the manufacturing impact. On
the other hand, the use of salt hydrates or ester as PCM in the cubicles results in an impact reduction of
9% and 10.5% respectively, compared to the case of using paraffin.
eng
info:eu-repo/semantics/restrictedAccess
(c) Elsevier, 2012
LCA
PCM
Ester
Life Cycle Assessment of experimental cubicles including PCM manufactured from natural resources (esters): a theoretical study
article
oai:repositori.udl.cat:10459.1/710202021-04-15T00:18:13Zcom_10459.1_238com_10459.1_2com_10459.1_239col_10459.1_309col_10459.1_10984
Baquero Armans, Grau
Esteban Dalmau, Bernat
Riba Ruiz, Jordi-Roger
Rius Carrasco, Antoni
Puig, Rita
2021-04-14T09:39:45Z
2021-04-14T09:39:45Z
2011-08
https://doi.org/10.1016/j.biombioe.2011.05.028
027745
0961-9534
http://hdl.handle.net/10459.1/71020
The use of straight vegetable oil (SVO) as biofuel has been recognized as a valid substitute of diesel fuel in the agricultural sector under specific circumstances. Its direct use reduces most of the chemical processes involved when converting it into biodiesel, thus lowering harmful emissions. This study presents the economic analysis of a self-supply farming model that uses rapeseed as its fuel base. This model addresses agricultural environmental concerns and can even minimize dependence on the fluctuating costs of diesel fuel. The use of SVO in agriculture can help reduce farmers’ vulnerability to fossil fuel prices. The economic evaluation of the model proposed in this study shows clear economic benefits of introducing rapeseed to the traditional crop rotation of wheat and barley. The key factors analyzed in this model are diesel fuel price, diesel fuel grants and crop aids. The current situation in Spain favors the use of diesel fuel in agriculture rather than rapeseed SVO due to an 8% profit difference. However, results show that changes in key factors slightly affect the profit margin, calculating a difference of only 3.7% for particular factor combinations. Combined environmental-friendly agriculture supporting policies are necessary to cover this slight profit difference to promote this biofuel.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd, (c) Elsevier, 2011
Straight vegetable oil
Brassica napus
Biofuel
Economic assessment
Self-supply
An evaluation of the life cycle cost of rapeseed oil as a straight vegetable oil fuel to replace petroleum diesel in agriculture
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/677772022-10-04T15:05:10Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Olacia, Elena
Pisello, Anna Laura
Chiodo, Vitaliano
Maisano, Susanna
Frazzica, Andrea
Cabeza, Luisa F.
2020-01-09T07:09:36Z
2021-12-23T23:20:44Z
2020
https://doi.org/10.1016/j.conbuildmat.2019.117669
029383
0950-0618
http://hdl.handle.net/10459.1/67777
There is an incipient necessity and interest of generating sustainable materials for application in green buildings. In this study, the capability of Posidonia Oceanica seagrass, a biomass by-product from the Mediterranean coastlines, is analysed as a reinforcement material in adobe bricks. For this purpose, earthen specimens with these sea-plant fibres were compared with the most traditional additives for this purpose, i.e. straw-based adobes. Both biomass fibres were included with different lengths and quantities. First, to understand their behaviour, the fibres were evaluated; water absorption and tensile strength tests were performed. Test specimens themselves were subjected to mechanical and thermal tests as well as measuring dimensional changes. Tested as fibres, straw presented higher tensile resistance and water absorption than seagrass; but tested within adobe specimens, straw containing samples had worse mechanical behaviour than those containing seagrass. Specially, adobe with Posidonia Ocenaica seagrass fibres with their natural long length showed to be the most suitable in terms of mechanical behaviour. Furthermore, good thermal conductivity results were achieved with this level of biomass reinforcement, generating a sustainable and value-added construction product.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd (c) Elsevier, 2019
Earth construction
Biomass by-products
Seagrass fibres
Mechanical and thermal properties
Sustainable composite
Building envelopes
Energy efficiency in buildings
Sustainable adobe bricks with seagrass fibres. Mechanical and thermal properties characterization
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/711772021-11-23T11:58:27Zcom_10459.1_238com_10459.1_2col_10459.1_309
Raugei, Marco
Fullana i Palmer, Pere
Puig, Rita
Torres, Alejo
2021-04-28T09:34:00Z
2021-04-28T09:34:00Z
2009-06
https://doi.org/10.1002/pts.865
027704
1099-1522
http://hdl.handle.net/10459.1/71177
This paper deals with a comparative analysis of two different packaging and transport
scenarios, which exemplifies the implications of choosing between single-use and
reusable packaging. In particular, transport of a batch of chemicals by means of
disposable fibre drums vs. reusable steel drums is investigated from a life cycle
perspective, and the associated environmental impact in terms of Global Warming
Potential, Acidification Potential, Gross Energy Requirement and solid waste generation
is assessed. Results prove beyond reasonable doubt that, even in the case of durable
packaging containers requiring the use of comparatively energy-intensive materials for
their production, the reuse scenario is characterized by lower environmental impact
indicators across the board, and as such is the most advisable and environmentally
sound option.
eng
info:eu-repo/semantics/openAccess
(c) Wiley, 2009
LCA
Packaging
Transport
Single-use
Reuse
A comparative life cycle assessment of single-use fibre drums versus reusable steel drums
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/658472022-09-23T17:27:30Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Durth, Melanie
Prieto, Cristina
Rodríguez-Sánchez, Alfonso
Patiño-Rodríguez, David
Cabeza, Luisa F.
2019-03-05T11:17:16Z
2021-02-22T23:30:23Z
2019
https://doi.org/10.1016/j.solener.2019.02.038
028389
0038-092X
http://hdl.handle.net/10459.1/65847
Thermal energy storage (TES) systems are key components of concentrating solar power plants in order to offer energy dispatchability to adapt the electricity power production to the curve demand. Nitrate molten salts are the storage media used today in concentrated solar power plants. They are also used as heat transfer fluid (HTF) in the molten salt tower (MST) technology. Traditional MST plants work in the temperature range of 240-565 °C using the so-called solar salt, a mixture of 60-40 wt% of NaNO3 and KNO3. This study wants to optimize the thermal energy storage cost of the solar concentration technology by analysing different mixtures of solar salts, using different percentages of NaNO3 and KNO3 in the mixture. The new mixtures seek a reduction in the cost of the storage material while optimizing its physical and chemical properties. The study shows how an increase in the proportion of sodium nitrate for a new binary solar salt to 78-22 wt%, produces an increase in the heat capacity of the mixture by reducing the necessary inventory of salts in the system. However, the new salt presents an increase in the melting point, going from 240 °C to 279 °C, which makes the operation of the system difficult. The impact on the cost of this optimization in the performance of a commercial plant was analysed. The plant chosen to evaluate the impact is a tower technology plant with 85 MWe power and 13 h of storage. The study shows a LCOE reduction of up to 0.6% for the new mixture with higher sodium nitrate.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd (c) Elsevier, 2019
Effects of sodium nitrate concentration on thermophysical properties of solar salts and on the thermal energy storage cost
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/664652022-09-26T15:43:50Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291
Calabrese, Luigi
Brancato, Vincenza
Palomba, Valeria
Frazzica, Andrea
Cabeza, Luisa F.
2019-06-19T10:22:51Z
2021-06-11T22:30:04Z
2019
https://doi.org/10.1016/j.solmat.2019.109992
028668
0927-0248
http://hdl.handle.net/10459.1/66465
This paper assesses the mechanical stability and dehydration behaviour of a new composite material constituted by magnesium sulphate hepta-hydrate, used as filler at vary contents, and a porous silicone, used as matrix in order to evaluate its applicability in sorption thermal energy storage field. This new composite was developed to avoid the typical issues of salt hydrates such as swelling, agglomeration and corrosion issues occurring during hydration/dehydration process. A preliminary physical-mechanical characterization, by means of morphological and calorimetric analysis, was carried out to investigate the main properties of the composite foams. The morphological characterization showed that the foam pores were homogenously distributed and well interconnected to each other. Thermogravimetric dehydration tests, have demonstrated that the tested samples are able to exchange efficiently water. Static compression tests evidenced a high compression stability of the material, indicating a high flexibility of the cellular silicone structure. Furthermore, cyclic compression test was performed to evaluate the progressive loss of salt at increasing number of the cycles. After 50 cycles, a reduction of salt hydrate up to 13% was observed. This behaviour, that is potentially a critical factor in these composite structures, was studied for showing that the loss of the salt does not compromise considerably the sorption storage performance of the filled silicone foams. Eventually, the assessment of thermo-gravimetric characteristics and mechanical stability was performed on the MgSO4·7H2O silicone composite foam.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd (c) Elsevier, 2019
MgSO4·7H2O
Composite foams
Thermochemical energy storage
Mechanical properties
TGA
Magnesium sulphate-silicone foam composites for thermochemical energy storage: Assessment of dehydration behaviour and mechanical stability
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/710572021-07-06T12:24:14Zcom_10459.1_238com_10459.1_2col_10459.1_309
Morera Prat, Josep M.
Bartolí, Esther
Borràs Fillat, Maria Dolors
Marsal Monge, Agustí
Costa López, José
2021-04-19T09:54:53Z
2021-04-19T09:54:53Z
1995
028300
0365-5873
http://hdl.handle.net/10459.1/71057
Se ha estudiado la curtición mixta vegetal-zinc sobre piel de cordero con el objetivo de obtener los datos necesarios que permitan optimizar el proceso en función del artículo final deseado.
Este tipo de curtición, exento de cromo, permite obtener cueros con temperaturas de contracción superiores a los 100ºC.
En este artículo se describe el estudio de la posible influencia del tipo de extracto y sal de zinc empleados, la temperatura, el recurtir o no en el mismo baño y el sistema de basificación en el producto final obtenido.
spa
info:eu-repo/semantics/openAccess
(c) AQEIC, 1995
Curtición mixta
Extracto vegetal
Zinc
Curtición mixta vegetal-zinc sobre piel de cordero. Parte IV
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/626352022-10-10T17:23:04Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291col_10459.1_44504
D'Alessandro, Antonella
Pisello, Anna Laura
Fabiani, Claudia
Ubertini, Filippo
Cabeza, Luisa F.
Cotana, Franco
2018-02-08T12:17:42Z
2020-02-06T23:23:11Z
2018
https://doi.org/10.1016/j.apenergy.2018.01.014
026679
0306-2619
http://hdl.handle.net/10459.1/62635
Energy performance in buildings and integrated systems represents a key aspect influencing anthropogenic emissions worldwide. Therefore, novel multifunctional materials for improving envelope thermo-energy efficiency through passive techniques are presently attracting notable researchers' effort. In this view, the integration of phase change materials (PCMs) into structural concrete showed interesting effects in enhancing the material thermal capacity while keeping proper structural strength. This work presents a multiphysics thermomechanical investigation concerning innovative concretes incorporating paraffin-based PCM suitable for structural-thermal multifunctional applications in high-energy efficiency building envelopes. Both classic microPCM-capsules and the novel more pioneering macroPCM-capsules with 18 °C phase transition temperature are used for the new composite preparation. Results confirm the thermal benefits of PCM and demonstrate that the addition of PCM reduces the mass density of concrete by almost twice PCMs weight. Average compressive strength decreases with increasing the amount of PCM, but its coefficient of variation is not as negatively affected, which is promising in terms of structural reliability. Indeed, a 1% weight content of microPCM and macroPCM results in reduced coefficients of variation of the compressive strength, determining an increase in characteristic compressive strength. This benefit might be associated to both a filler effect of the PCM and to a positive thermal interaction between inclusions and cement hydration products. The multifunctional analysis showed promising performance of PCM-based macro-capsules as aggregates, even if their concentration is relatively minor than the classic micro-capsules already acknowledged as effective additives for high energy efficient cement-based materials.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/3.0/es
cc-by-nc-nd, (c) Elsevier, 2018
Phase change materials
Thermal-energy storage
Cement-based composites
Structural concrete
Smart multifunctional materials
Building envelope
Multifunctional smart concretes with novel phase change materials: Mechanical and thermo-energy investigation
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/4646652023-12-06T03:00:34Zcom_10459.1_238com_10459.1_2col_10459.1_309
Palacín Roca, Jordi
Rubies, Elena
Bitriá, Ricard
Clotet Bellmunt, Eduard
2023-12-05T08:47:59Z
2023-12-05T08:47:59Z
2023
https://doi.org/10.3390/s23218795
1424-8220
https://repositori.udl.cat/handle/10459.1/464665
Planning the path of a mobile robot that must transport and deliver small packages inside a multi-story building is a problem that requires a combination of spatial and operational information, such as the location of origin and destination points and how to interact with elevators. This paper presents a solution to this problem, which has been formulated under the following assumptions: (1) the map of the building’s floors is available; (2) the position of all origin and destination points is known; (3) the mobile robot has sensors to self-localize on the floors; (4) the building is equipped with remotely controlled elevators; and (5) all doors expected in a delivery route will be open. We start by defining a static navigation tree describing the weighted paths in a multi-story building. We then proceed to describe how this navigation tree can be used to plan the route of a mobile robot and estimate the total length of any delivery route using Dijkstra’s algorithm. Finally, we show simulated routing results that demonstrate the effectiveness of this proposal when applied to an autonomous delivery robot operating in a multi-story building.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by/4.0/
cc-by (c) Jordi Palacín et al., 2023
Attribution 4.0 International
Mobile robot
Path planning
Dijkstra’s algorithm
Package delivery
Multi-story building
Path Planning of a Mobile Delivery Robot Operating in a Multi-Story Building Based on a Predefined Navigation Tree
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/849932023-11-14T12:55:39Zcom_10459.1_238com_10459.1_2col_10459.1_309
Díaz-Reza, José Roberto
García-Alcaraz, Jorge Luis
Márquez Figueroa, Luis Javier
Puig, Rita
Sáenz Díez Muro, Juan Carlos
2022-12-21T10:07:40Z
2022-12-21T10:07:40Z
2022-10-12
https://doi.org/10.1007/s00170-022-10208-0
032902
0268-3768
http://hdl.handle.net/10459.1/84993
Traditionally, the isolated relationship of total preventive maintenance (TPM), quick setup (QS), overall equipment effec- tiveness (OEE), and one-piece flow (OPF) with economic sustainability (ESU) has been investigated; however, these lean manufacturing (LM) tools are implemented together into production systems, and traditional research does not report their relationships and interactions. To contribute to this gap, this paper integrates all those variables in a structural equation model (SEM), which are related by seven hypotheses that are validated using the partial least squares (PLS) technique using information from 176 responses to a questionnaire applied to the Mexican maquiladora industry. Additionally, a sensitivity analysis has been carried out to determine the probability of occurrence at high and low implementation levels for all variables when they occur in isolation, jointly and conditionally. Findings indicate that TPM is a precursor of QS and OEE, while QS is a precursor of OEE and OPF, OEE is a precursor of OPF and ESU, but also OPF is a precursor of ESU. The sensitivity analysis indicates that low levels of TPM are a risk for reaching adequate levels of OEE and QC, while low levels in OEE and OPF are a risk for reaching adequate ESU levels.
eng
info:eu-repo/semantics/openAccess
(c) Díaz-Reza, José Roberto et al., 2022
Lean manufacturing
Economic sustainability
TPM
Structural equations
Relationship between lean manufacturing tools and their sustainable economic benefits
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/655742022-10-10T18:25:26Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291col_10459.1_44504
Galazutdinova, Yana
Grágeda, Mario
Cabeza, Luisa F.
Ushak, Svetlana
2019-01-21T07:48:01Z
2019-01-21T07:48:01Z
2017
https://doi.org/10.1002/er.3805
028215
0363-907X
http://hdl.handle.net/10459.1/65574
In this study, an inorganic mixture based on bischofite (industrial by‐product) was developed and characterized for its application as a phase change material for low‐temperature thermal energy storage. The most appropriate composition was established as 40 wt% bischofite and 60 wt% Mg(NO3)2 · 6H2O. Thermophysical properties were defined and compared with those of the mixture with synthetic MgCl2 · 6H2O. The heat of fusion and melting temperature were measured as 62.0°C and 132.5 kJ kg−1 for the mixture with MgCl2 · 6H2O and 58.2°C and 116.9 kJ kg−1 for the mixture with bischofite. The specific heat capacity values, cycling, and thermal stability for both mixtures were also determined. For the mixture with MgCl2 · 6H2O, the densities of the solid and liquid states were 1517 kg m−3 (ambient temperature) and 1515 kg m−3 (at 60‐70°C), respectively. For the mixture with bischofite, the densities of the solid and liquid states were 1525 kg m−3 (ambient temperature) and 1535 kg m−3 (at 60‐70°C), respectively. Both mixtures show supercooling of about 23.4 and 34.1°C for the mixture with bischofite and MgCl2 · 6H2O, respectively. In addition, it was shown that supercooling may be reduced by increasing the quantity of material tested. Thereby, it was established that an inorganic mixture based on bischofite is a promising PCM for low‐temperature thermal energy storage applications.
eng
info:eu-repo/semantics/openAccess
(c) John Wiley & Sons, 2017
Phase change material
Salt hydrate mixture
Thermal energy storage
Waste or by‐products
Novel inorganic binary mixture for low‐temperature heat storage applications
info:eu-repo/semantics/article
oai:repositori.udl.cat:10459.1/602132022-09-28T14:20:31Zcom_10459.1_238com_10459.1_2com_10459.1_56939col_10459.1_309col_10459.1_56941col_10459.1_49291col_10459.1_44504
Navarro Farré, Lidia
Barreneche Güerisoli, Camila
Castell, Albert
Redpath, David A.G.
Griffiths, Philip
Cabeza, Luisa F.
2017-09-05T07:33:51Z
2019-10-31T23:17:00Z
2017
https://doi.org/10.1016/j.est.2017.07.025
025868
2352-152X
http://hdl.handle.net/10459.1/60213
Renewable energy is a potential alternative energy provider with fewer CO2 emissions. However, the mismatch between energy supply and demand is the main disadvantage. Therefore, thermal energy storage becomes an essential technology for enhancing renewable energy efficiency and providing energy supply to the end user. In solar thermal energy systems, hot water tanks are widely used as sensible heat storage technology. Moreover, water storage usually requires large volumes and their improvement has been studied in terms of shape and arrangement. Latent heat storage materials are a potential technology for implementation in water storage tanks in order to reduce their volume and to enhance their efficiency. In this paper, the incorporation of shape high density polyethylene spheres with PCM into domestic hot water tanks is studied. Undesired results obtained in the water tank set-up lead the authors to analyse the PCM leakage in the laboratory. Laboratory analysis pointed out that the PCM-spheres must be thermally cycled and cleaned before their implementation in real application of domestic hot water in order to stabilize the PCM content inside the PCM- spheres.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
cc-by-nc-nd (c) Elsevier, 2017
Thermal energy storage (TES)
Water tank
Phase change materials (PCM)
Encapsulation
Stabilization
High density polyethylene spheres with PCM for domestic hot water applications: Water tank and laboratory scale study
info:eu-repo/semantics/article
mods///col_10459.1_309/100