3,101 research outputs found
Design of a System for the Production of Domestic Hot Water from Wastewater Heat Recovery Based on a Heat Pump Optimized to Work at High Water Temperature Lift
Although many efforts towards more energy-efficient houses have been done, the domestic hot water (DHW) production represents still 18% of the energy consumption in the US domestic sector and will remain roughly similar in the future. Water from the sewage in the domestic sector or from condensing loops in tertiary sector is a potential heat source usually wasted to the ambient. The main potential of this source -apart from energy recuperation- is its temperature, which is slightly higher than the ambient (20-40ºC) and that it does not have significant variability neither through the year nor through the day and its availability. The main objective of the present work is to study the best system configuration in order to use this heat source to satisfy the DHW demand. The solution founded is composed of an initial heat exchanger, a water-to-water heat pump (WtWHP) and a hot water storage tank. The wastewater flow passes through a heat exchanger in order to preheat the DHW. Later on, it is used as a heat source in the evaporator of the WtWHP. The WtWHP increases the temperature of the preheated DHW up to 60 ºC. Finally, the water is stored in a tank at this temperature. The WtWHP has being optimized from the exergetic point of view in order to be able to work with high water temperature lift in the condenser in subcritical conditions with a high COP. This is possible by the integration of a control system that optimizes the subcooling in the condenser based on external conditions and a liquid to suction heat exchanger. The WtWHP configured in this way is able to work at COPs up to 6. The produced water is stored in a hot water storage tank at uniform temperature. The size of the binomial WtWHP-tank has been optimized in order to minimize the energy consumption of the system. Finally, annual energy consumption and CO2 emissions of the final configuration has been calculated and compared with the obtained using a gas boiler with the same profile demand
Optimal sizing of a heat pump booster for sanitary hot water production to maximize benefit for the substitution of gas boilers
[EN] Heat recovery from water sources such as sewage water or condensation loops at low temperatures (usually between 10 and 30 °C) is becoming very valuable. Heat pumps are a potential technology able to overcome the high water temperature lift of the Sanitary Hot Water (SHW) application (usually from 10 °C to 60 °C with COPs up to 6). This paper presents a model to find the optimal size of a system (heat pump and recovery heat exchanger) based on water sources to produce SHW compared to the conventional production with a gas boiler in order to maximize the benefit. The model includes a thermal and economic analysis for a base case and analyzes the influence of a wide set of parameters which could have a significant influence. Even the uncertainties involved, results point out considerable benefits from this substitution based on the capacity of the system. Thus, demonstrating the importance of the optimal size analysis before an investment is done.Part of the work presented was carried by Estefania Hervas Blasco with the financial support of a PhD scholarship from the Spanish government SFPI1500X074478XV0. Part of the work presented was carried by Miguel Pitarch-Mocholi with the financial support of a PhD scholarship from the Universitat Politecnica de Valencia. The authors would like also to acknowledge the Spanish 'MINISTERIO DE ECONOMIA Y COMPETITIVIDAD', through the project ref-ENE2014-53311-C2-1-P-AR "Aprovechamiento del calor residual a baja temperatura mediante bombas de calor para la produccion de agua caliente" for the given supportHervas-Blasco, E.; Pitarch, M.; Navarro-Peris, E.; Corberán, JM. (2017). Optimal sizing of a heat pump booster for sanitary hot water production to maximize benefit for the substitution of gas boilers. Energy. 127:558-570. https://doi.org/10.1016/j.energy.2017.03.13155857012
Potential fuel saving in a powertrain derived from the recovery of the main energy losses for a long haul European mission
[EN] The reduction of automotive fuel consumption and emissions remains one of the main challenges. This paper presents the potential fuel saving in a CNG-powertrain derived from the recovery of the main energy losses. The analysis includes the kinetic energy recovery by a belt starter generator (BSG), the exhaust gas waste heat recuperation by using in a cascade approach, a thermoelectric generator (TEG) and a turbo-generator (TBG)- and the electrification of the main auxiliaries. An additional 48 V board net as well as the addition of a storage system are also included in the study. To support on the design phase of the project and in the operation strategy, a dynamic model in Matlab/Simulink (R) has been used. The model includes all the new components/major changes required in the vehicle- experimentally validated-. It has been used on backward simulations for the ACEA long haul mission in order to maximize the vehicle's efficiency.
Estimations at rating point (600 Nm and 1200 rpm) result in an electric production up to 4 kW h and a fuel saving of 7.5%. The most convenient technologies in the ACEA cycle turns out to be the KERs followed by the TBG.This work has been developed in the frame of the project of the European Seventh Union Framework Program by the project High efficiency energy conversion for future heavy duty transport High efficiency energy conversion for future heavy duty transport GASTone grant agreement 605456. The authors are grateful for the given support.Hervas-Blasco, E.; Navarro-Peris, E.; De Rosa, M.; Corberán, JM. (2017). Potential fuel saving in a powertrain derived from the recovery of the main energy losses for a long haul European mission. Energy Conversion and Management. 150:485-499. https://doi.org/10.1016/j.enconman.2017.08.01848549915
Energy optimization of a thermal storage tank for Domestic Hot Water production
[EN] According to the European Commission, the residential sector is responsible at this moment of the 40 % of the energy consumption and 36 % of the associated CO2 emissions in Europe. Regarding the water heating consumption, it is currently responsible for 14.5 % energy consumption of the average European dwelling. This percentage is expected to increase drastically within the concept of Near Zero Energy Building (NZEB) since the associated heating consumption percentage will be decreased largely. In this way, the energy consumption associated for water heating should be reduced, and it only can be done by using highly energy efficient technologies, such as heat pump (HP), and decreasing the energy losses associated to the facilities.
In the frame of the European Project NEXTHPG of the 7th framework program, a new prototype of heat pump booster for the production of domestic hot water was developed. The developed prototype uses an innovative subcooling control system, which allows increasing the COP of the system in more than 30% compared to conventional subcritical heat pump systems. Nevertheless, in a real installation apart from the heat pump there are other factors contributing to the final energy consumption of the whole system like system configuration, control algorithm, tank size and the like. Therefore, an estimation of the final energy consumption of the system could be significantly different from the obtained taking into account only the pump performance.
The present work is focused on the development of a model in order to optimize the design of the whole system using the prototype of the NEXTHPG project in order to satisfy the domestic hot water demand of a building for 20 people. The integrated system model will include the heat pump, the water tank, a heat exchanger in order to recover part of the waste heat (such as the heat coming from the sewage water in the domestic sector or from condensing loops in tertiary sector) and a random generator of domestic hot water demand profile.
From the results of this work, the proper sizing of the heat pump and the water tank, as well as the control algorithm, are obtained and the potential annual energy consumption of this type of system is estimated.Part of the work presented was carried by Estefanía Hervás Blasco with the financial support of
a PhD scholarship from the Spanish government SFPI1500 x 074478XV0. The authors would
like also to acknowledge the Spanish MINISTERIO DE ECONOMIA Y COMPETITIVIDAD¿,
thorugh the project. MAXIMIZACION DE LA EFICIENCIA Y MINIMIZACION DEL
IMPACTO AMBIENTAL DE BOMBAS DE CALOR PARA LA DESCARBONIZACION DE
LA CALEFACCION/ACS EN LOS EDIFICIOS DE CONSUMO CASI NULO with the
reference ENE2017-83665-C2-1-P for the given support and REDUCCIÓN DE LAS
EMISIONES DE CO2 EN LA PRODUCCIÓN DE AGUA CALIENTE A ALTA
TEMPERATURA A PARTIR DE LA RECUPERACIÓN DE CALOR RESIDUAL MEDIANTE
EL USO DE UNA BOMBA DE CALOR with the reference SP20180039.Masip, X.; Álvarez-Piñeiro, L.; Hervas-Blasco, E.; Navarro-Peris, E.; Corberán, JM. (2019). Energy optimization of a thermal storage tank for Domestic Hot Water production. Universidad de Castilla-La Mancha
José Antonio Almendros Ibáñez. 167-175. http://hdl.handle.net/10251/180696S16717
Aplicabilidad de la tecnologia movil en residencias y centros especializados
Uno de los principales esfuerzos de nuestro trabajo radica en aprovechar las capacidades de dispositivos móviles universales como los teléfonos móviles y sensores autónomos integrados, permitiendo la obtención de servicios del entorno y la realización de tareas esenciales en el día a día de centros residenciales y sanitarios. Por tanto, se presentan distintos desarrollos de aplicabilidad de estos dispositivos en los entornos mencionados. La integración y adaptación de nuevas tecnologías en entornos residenciales, centros especializados y hospitales es hoy en día una realidad a la par que una necesidad inherente, aún más tratándose de entornos tan heterogéneos y dispersos como los citados anteriormente. Por ello, el concepto de movilidad desarrollado por las diferentes tecnologías móviles existentes se presenta como una de las principales alternativas y soluciones para dar soporte al profesional en sus tareas diarias, así como mejorar la calidad asistencial de los pacientes y residentes de estos centros. Sin embargo, esta adaptación tecnológica debe presentarse de forma natural, intuitiva y no intrusiva de cara al personal sanitario y a los propios pacientes.Uno de los principales esfuerzos de nuestro trabajo radica en aprovechar las capacidades de dispositivos móviles universales como los teléfonos móviles y sensores autónomos integrados, permitiendo la obtención de servicios del entorno y la realización de tareas esenciales en el día a día de centros residenciales y sanitarios. Por tanto, se presentan distintos desarrollos de aplicabilidad de estos dispositivos en los entornos mencionados. La integración y adaptación de nuevas tecnologías en entornos residenciales, centros especializados y hospitales es hoy en día una realidad a la par que una necesidad inherente, aún más tratándose de entornos tan heterogéneos y dispersos como los citados anteriormente. Por ello, el concepto de movilidad desarrollado por las diferentes tecnologías móviles existentes se presenta como una de las principales alternativas y soluciones para dar soporte al profesional en sus tareas diarias, así como mejorar la calidad asistencial de los pacientes y residentes de estos centros. Sin embargo, esta adaptación tecnológica debe presentarse de forma natural, intuitiva y no intrusiva de cara al personal sanitario y a los propios pacientes
Diagnóstico y seguimiento de la fragilidad en ancianos mediante el uso de dispositivos móviles
Con la edad, la resistencia y las reservas fisiológicas de una persona adulta disminuyen, provocando un mayor riesgo de sufrir efectos adversos para la salud. Estos factores llevan al conocido estado de fragilidad. El término fragilidad es difícil de conceptualizar, aunque en la mayoría de los casos está relacionado con el envejecimiento, discapacidad o comorbilidad. En la actualidad, la detección de la fragilidad se realiza mediante la observación en la ejecución de las AVD e AIVD, pruebas de marcha y equilibrio, y evaluación de parámetros nutricionales y cognitivos. Sin embargo, su valoración depende del punto de vista del geriatra o facultativo, cuyo diagnóstico se realiza en función de la puntuación obtenida en distintas escalas (Índice de Barthel, Tinetti, Lawton, MMS,...) y a partir de su propia observación. En este trabajo se presenta un sistema de apoyo al personal sanitario de residencias y centros especializados, para la detección de la fragilidad en ancianos mediante el uso de dispositivos móviles con sensores acelerómetros, en combinación con el historial clínico del residente.Con la edad, la resistencia y las reservas fisiológicas de una persona adulta disminuyen, provocando un mayor riesgo de sufrir efectos adversos para la salud. Estos factores llevan al conocido estado de fragilidad. El término fragilidad es difícil de conceptualizar, aunque en la mayoría de los casos está relacionado con el envejecimiento, discapacidad o comorbilidad. En la actualidad, la detección de la fragilidad se realiza mediante la observación en la ejecución de las AVD e AIVD, pruebas de marcha y equilibrio, y evaluación de parámetros nutricionales y cognitivos. Sin embargo, su valoración depende del punto de vista del geriatra o facultativo, cuyo diagnóstico se realiza en función de la puntuación obtenida en distintas escalas (Índice de Barthel, Tinetti, Lawton, MMS,...) y a partir de su propia observación. En este trabajo se presenta un sistema de apoyo al personal sanitario de residencias y centros especializados, para la detección de la fragilidad en ancianos mediante el uso de dispositivos móviles con sensores acelerómetros, en combinación con el historial clínico del residente
Blockade of the Interaction of Calcineurin with FOXO in Astrocytes Protects Against Amyloid-beta-Induced Neuronal Death
Astrocytes actively participate in neuro-inflammatory processes associated to Alzheimer's disease (AD), and other brain pathologies. We recently showed that an astrocyte-specific intracellular signaling pathway involving an interaction of the phosphatase calcineurin with the transcription factor FOXO3 is a major driver in AD-associated pathological inflammation, suggesting a potential new druggable target for this devastating disease. We have now developed decoy molecules to interfere with calcineurin/FOXO3 interactions, and tested them in astrocytes and neuronal co-cultures exposed to amyloid-beta (A beta) toxicity. We observed that interference of calcineurin/FOXO3 interactions exerts a protective action against A beta-induced neuronal death and favors the production of a set of growth factors that we hypothesize form part of a cytoprotective pathway to resolve inflammation. Furthermore, interference of the A beta-induced interaction of calcineurin with FOXO3 by decoy compounds significantly decreased amyloid-beta protein precursor (A beta PP) synthesis, reduced the A beta PP amyloidogenic pathway, resulting in lower A beta levels, and blocked the expression of pro-inflammatory cytokines TNF alpha and IL-6 in astrocytes. Collectively, these data indicate that interrupting pro-inflammatory calcineurin/FOXO3 interactions in astrocytes triggered by A beta accumulation in brain may constitute an effective new therapeutic approach in AD. Future studies with intranasal delivery, or brain barrier permeable decoy compounds, are warranted.Peer ReviewedPostprint (author's final draft
Study of different subcooling control strategies in order to enhance the performance of a heat pump
[EN] The performance of vapor-compression systems working with subcritical refrigerants varies with the degree of subcooling. There is an optimal subcooling that maximizes efficiency. However, it depends on the operating conditions and the control of the system needs to be adapted. Most of the works available in literature are able to operate in optimal conditions only at the design point or if a system is designed to be able to adapt its subcooling, only complex control algorithms that usually are difficult to set and time-costly, are used. This work focuses on the study of the main variables influencing the optimal subcooling and analyzes two different control methodologies from the theoretical point of view. Based on the theoretical study a final control strategy is selected and tested experimentally. The reliability, stability and robustness of the selected strategy are experimentally demonstrated for a wide set of operating conditions. (c) 2018 Elsevier Ltd and IIR. All rights reserved.Part of the work presented was carried by Estefania Hervas Blasco with the financial support of a PhD scholarship from the Spanish government SFPI1500 x 074478XV0. The authors would like also to acknowledge the Spanish 'MINISTERIO DE ECONOMIA Y COMPETITIVIDAD', through the project. "MAXIMIZACION DE LA EFICIENCIA Y MINIMIZACION DEL IMPACTO AMBIENTAL DE BOMBAS DE CALOR PARA LA DESCARBONIZACION DE LA CALEFACCION/ACS EN LOS EDIFICIOS DECONSUMO CASI NULO" with the reference ENE2017-83665-C2-1-P for the given support.Hervas-Blasco, E.; Pitarch, M.; Navarro-Peris, E.; Corberán, JM. (2018). Study of different subcooling control strategies in order to enhance the performance of a heat pump. International Journal of Refrigeration. 88:324-336. https://doi.org/10.1016/j.ijrefrig.2018.02.003S3243368
ARQUEOTOPOS Project. Harbour of Cartagena an approach from the Paleotopography and Geoarcheology
-
Functional characterization of the evolutionarily divergent fern plastocyanin
De functie van eiwitten die betrokken zijn bij insulinewerking en glucose hemeostrase en de rol van genetische varianten hierin bij de ontwikkeling van type 2 diabete
- …