The Experts below are selected from a list of 24177 Experts worldwide ranked by ideXlab platform

Lijiu Wang - One of the best experts on this subject based on the ideXlab platform.

  • research on heat transfer performance of passive solar collector Storage Wall system with phase change materials
    Energy and Buildings, 2016
    Co-Authors: Dan Sun, Lijiu Wang
    Abstract:

    Abstract Heat transfer performance on the Wall has a great influence on energy conservation and indoor thermal comfort. In this paper, a new type of passive solar energy utilization technology, phase change materials (PCMs) added into passive solar collector-Storage Wall system was proposed. Heat transfer performance and energy saving characteristics were investigated theoretically and experimentally. Energy balance equations that including sunlight board, air in the channel, collector mortar layer and inner surface of Wall were established to describe the heat transfer process of system. Experimental room was used to studied the energy saving characteristics in winter. The results indicate that the new passive solar collector-Storage Wall system with PCMs can promote indoor air thermal circulation and decrease indoor air temperature fluctuations. Its good heat Storage capacity can apparently improve indoor thermal environment. Therefore, this new passive solar collector-Storage Wall system with PCMs can be popularized in engineering applications.

Dan Sun - One of the best experts on this subject based on the ideXlab platform.

  • Thermal Feature of a Modified Solar Phase Change Material Storage Wall System
    International Journal of Photoenergy, 2018
    Co-Authors: Chenglong Luo, Mengyin Liao, Dan Sun
    Abstract:

    This work is to study a novel solar PCM Storage Wall technology, that is, a dual-channel and thermal-insulation-in-the-middle type solar PCM Storage Wall (MSPCMW) system. The system has the following four independent functions, passive solar heating, heat preservation, heat insulation, and passive cooling, and it can agilely cope with the requirements of climatization of buildings in different seasons throughout the year and is exactly suitable for building in regions characterized by hot summer and cold winter. The present work experimentally analyzes thermal feature of the system working in summer and winter modes, respectively.

  • Comparative Research on Solar Phase Change Material Storage Wall Systems under Different Summer Working Conditions
    Energies, 2017
    Co-Authors: Chenglong Luo, Dan Sun, Jihai Xiong, Mengyin Liao
    Abstract:

    To study and analyze the performance characteristics and the effectiveness of the system under practical application scenarios, the present work compares the performance of solar energy phase change material Storage Wall systems suitable for buildings in hot summer and cold winter regions under different summer working conditions. The experimental facility was installed on light-weight insulation Wall and ordinary Wall; ventilation conditions of shutting/opening doors and windows, respectively, were set. The experimental facility showed different thermal characteristics when it was installed on insulation Wall and on solid Wall whether it was vented or not; under vented working condition, the temperature of the external surface of the south-facing Wall which attached to the solid Wall experimental system was lower, demonstrating that under practical building scenarios the present technology could better reveal its capability of avoiding the overheating issue of the solar heating Wall in summer.

  • Experimental study of a modified solar phase change material Storage Wall system
    Energy, 2017
    Co-Authors: Chenglong Luo, Mengyin Liao, Dan Sun
    Abstract:

    Abstract Aiming at satisfying demands of buildings in hot summer and cold winter regions, this work proposed a dual-channel and thermal-insulation-in-the-middle type solar phase change material Storage Wall system. The system has four independent functions: passive solar heating, heat preservation, heat insulation, and passive cooling, and it can agilely cope with requirements of climatization of buildings in different seasons throughout the year. The analysis of measured data from comparative tests on a hot-box test platform, shows that in summer, the daily average temperatures in the experimental room are 29.8 °C, 30.9 °C and 31.0 °C respectively, while those in the reference room are 29.6 °C, 30.7 °C and 30.8 °C, and thereby the difference is small. The south-facing Wall with solar collector module shows reduction in peak temperature and delay phenomenon compared with that without solar collector module. These aspects highlighted by the results together indicate that effective prevention from summer overheating problem can be achieved by this system. In winter, by comparison with the ambient temperatures and those of the reference room, the air temperatures in the experimental room, both its maximum and average, raise greatly showing good heating effect. In addition, some distinct thermal characteristics of the system operated in summer or winter are obtained.

  • research on heat transfer performance of passive solar collector Storage Wall system with phase change materials
    Energy and Buildings, 2016
    Co-Authors: Dan Sun, Lijiu Wang
    Abstract:

    Abstract Heat transfer performance on the Wall has a great influence on energy conservation and indoor thermal comfort. In this paper, a new type of passive solar energy utilization technology, phase change materials (PCMs) added into passive solar collector-Storage Wall system was proposed. Heat transfer performance and energy saving characteristics were investigated theoretically and experimentally. Energy balance equations that including sunlight board, air in the channel, collector mortar layer and inner surface of Wall were established to describe the heat transfer process of system. Experimental room was used to studied the energy saving characteristics in winter. The results indicate that the new passive solar collector-Storage Wall system with PCMs can promote indoor air thermal circulation and decrease indoor air temperature fluctuations. Its good heat Storage capacity can apparently improve indoor thermal environment. Therefore, this new passive solar collector-Storage Wall system with PCMs can be popularized in engineering applications.

Ehsan F Abbas - One of the best experts on this subject based on the ideXlab platform.

  • a comparative performance study of some thermal Storage materials used for solar space heating
    Energy and Buildings, 2009
    Co-Authors: Abdul Jabbar N. Khalifa, Ehsan F Abbas
    Abstract:

    One of the most common methods used in passive heating is the utilization of a massive Wall for heat Storage. Many factors affect the performance of the Wall, such as the thickness and the media used for heat Storage. A numerical study has been conducted on a zone heated by a thermal Storage Wall. Three different Storage materials are examined, namely concrete, the hydrated salt CaCl2·6H2O and paraffin wax (N-eicosane). A numerical model is presented in this paper which judges the suitability of these materials as thermal Storage mediums under the actual weather conditions of Iraq. For that purpose, the room temperature fluctuation in the zone is evaluated for each material using different thickness for each Wall. The study concluded that an 8-cm-thick Storage Wall made from the hydrated salt is capable of maintaining the comfort temperature in the zone with the least room temperature fluctuation.

Abdul Jabbar N. Khalifa - One of the best experts on this subject based on the ideXlab platform.

  • a comparative performance study of some thermal Storage materials used for solar space heating
    Energy and Buildings, 2009
    Co-Authors: Abdul Jabbar N. Khalifa, Ehsan F Abbas
    Abstract:

    One of the most common methods used in passive heating is the utilization of a massive Wall for heat Storage. Many factors affect the performance of the Wall, such as the thickness and the media used for heat Storage. A numerical study has been conducted on a zone heated by a thermal Storage Wall. Three different Storage materials are examined, namely concrete, the hydrated salt CaCl2·6H2O and paraffin wax (N-eicosane). A numerical model is presented in this paper which judges the suitability of these materials as thermal Storage mediums under the actual weather conditions of Iraq. For that purpose, the room temperature fluctuation in the zone is evaluated for each material using different thickness for each Wall. The study concluded that an 8-cm-thick Storage Wall made from the hydrated salt is capable of maintaining the comfort temperature in the zone with the least room temperature fluctuation.

  • A study on a passively heated single-zone building using a thermal Storage Wall
    Energy Conversion and Management, 1998
    Co-Authors: Abdul Jabbar N. Khalifa
    Abstract:

    Abstract The thermal performance of a passively heated zone is predicted by calculating the transient temperature variation of each node in the system using a finite-difference model. The sensitivity of the zone air temperature to the change in some of the zone features is examined. Some of these parameters included the thickness of the Walls, using constant and variable heat transfer coefficients, having controlled and uncontrolled thermocirculation in a vented Storage Wall.

Mengmeng Pang - One of the best experts on this subject based on the ideXlab platform.

  • experimental investigations on the performance of a collector Storage Wall system using phase change materials
    Energy Conversion and Management, 2015
    Co-Authors: Guobing Zhou, Mengmeng Pang
    Abstract:

    Abstract Experiments have been performed on the thermal behavior of a collector–Storage Wall system using PCM (phase change material). PCM slabs were attached on the gap-side Wall surface to increase the heat Storage. The test was carried out for a whole day with charging period of 6.5 h and discharging period of 17.5 h, respectively. Wall and air temperatures as well as air velocity in the gap were measured for analysis. The results showed that the PCM surface temperature increases first rapidly, then slowly and rapidly again during the charging process, which in turn corresponds with the three Storage stages: sensible heat (solid), latent heat (melting) and sensible heat (liquid), respectively; while in the discharging process the PCM surface temperature decreases slightly shortly after the initial sharp drops, which suggests the long time period of solidification for PCM to release latent heat. Subject to the variations of PCM surface temperatures, similar trends were also found for the gap air temperatures, glazing temperature and indoor temperature. Both the air flow rate and heating rate by air circulation have up and down fluctuations during the charging period, and then, shortly after initial sharp drops, they keep at nearly steady values during the discharging period. The indoor temperature was found to be above 22 °C during the whole discharging period (17.5 h) under present conditions, which indicates that the indoor thermal comfort could be kept for a long time by using PCM in collector–Storage Wall system.

  • Experimental investigations on the performance of a collector–Storage Wall system using phase change materials
    Energy Conversion and Management, 2015
    Co-Authors: Guobing Zhou, Mengmeng Pang
    Abstract:

    Abstract Experiments have been performed on the thermal behavior of a collector–Storage Wall system using PCM (phase change material). PCM slabs were attached on the gap-side Wall surface to increase the heat Storage. The test was carried out for a whole day with charging period of 6.5 h and discharging period of 17.5 h, respectively. Wall and air temperatures as well as air velocity in the gap were measured for analysis. The results showed that the PCM surface temperature increases first rapidly, then slowly and rapidly again during the charging process, which in turn corresponds with the three Storage stages: sensible heat (solid), latent heat (melting) and sensible heat (liquid), respectively; while in the discharging process the PCM surface temperature decreases slightly shortly after the initial sharp drops, which suggests the long time period of solidification for PCM to release latent heat. Subject to the variations of PCM surface temperatures, similar trends were also found for the gap air temperatures, glazing temperature and indoor temperature. Both the air flow rate and heating rate by air circulation have up and down fluctuations during the charging period, and then, shortly after initial sharp drops, they keep at nearly steady values during the discharging period. The indoor temperature was found to be above 22 °C during the whole discharging period (17.5 h) under present conditions, which indicates that the indoor thermal comfort could be kept for a long time by using PCM in collector–Storage Wall system.