The Experts below are selected from a list of 138 Experts worldwide ranked by ideXlab platform

Xu Liu - One of the best experts on this subject based on the ideXlab platform.

  • Experimental study on cool storage air-conditioning system with spherical capsules packed bed
    Energy and Buildings, 2010
    Co-Authors: Guiyin Fang, Xu Liu
    Abstract:

    Abstract An experimental investigation on operation characteristics of cool storage air-conditioning system with spherical capsules packed bed was performed in this paper. The experimental system of cool storage air-conditioning system with spherical capsules packed bed was set up. The performance parameters such as the evaporation pressure and the condensation pressure of refrigeration system, the refrigeration capacity and the coefficient of performance (COP) of the system, the cool storage rate and the cool storage capacity in the cool storage tank, the inlet and outlet coolant temperatures in the cool storage tank during charging Period, and the cool discharge rate and the cool discharge capacity in the cool storage tank, the outlet and inlet coolant temperatures in the cool storage tank and the outlet and inlet air temperatures in room fan coil unit during Discharging Period were investigated. The experimental results indicated that the cool storage air-conditioning system with spherical capsules packed bed has better performances and can stably work during charging and Discharging Period.

  • Experimental investigation on performance of ice storage air-conditioning system with separate heat pipe
    Experimental Thermal and Fluid Science, 2009
    Co-Authors: Guiyin Fang, Xu Liu
    Abstract:

    An experimental study on operation performance of ice storage air-conditioning system with separate helical heat pipe is conducted in this paper. The experimental system of ice storage air-conditioning system with separate heat pipe is set up. The performance parameters such as the evaporation pressure and the condensation pressure of refrigeration system, the refrigeration capacity and the COP (coefficient of performance) of the system, the IPF (ice packing factor) and the cool storage capacity in the cool storage tank during charging Period, and the cool discharge rate and the cool discharge capacity in the cool storage tank, the outlet water temperature in the cool storage tank and the outlet air temperature in room unit during Discharging Period are investigated. The experimental results show that the ice storage air-conditioning system with separate helical heat pipe can stably work during charging and Discharging Period. This indicates that the ice storage air-conditioning system with separate helical heat pipe is well adapted to cool storage air-conditioning systems in building.

Guiyin Fang - One of the best experts on this subject based on the ideXlab platform.

  • Experimental study on cool storage air-conditioning system with spherical capsules packed bed
    Energy and Buildings, 2010
    Co-Authors: Guiyin Fang, Xu Liu
    Abstract:

    Abstract An experimental investigation on operation characteristics of cool storage air-conditioning system with spherical capsules packed bed was performed in this paper. The experimental system of cool storage air-conditioning system with spherical capsules packed bed was set up. The performance parameters such as the evaporation pressure and the condensation pressure of refrigeration system, the refrigeration capacity and the coefficient of performance (COP) of the system, the cool storage rate and the cool storage capacity in the cool storage tank, the inlet and outlet coolant temperatures in the cool storage tank during charging Period, and the cool discharge rate and the cool discharge capacity in the cool storage tank, the outlet and inlet coolant temperatures in the cool storage tank and the outlet and inlet air temperatures in room fan coil unit during Discharging Period were investigated. The experimental results indicated that the cool storage air-conditioning system with spherical capsules packed bed has better performances and can stably work during charging and Discharging Period.

  • Experimental investigation on performance of ice storage air-conditioning system with separate heat pipe
    Experimental Thermal and Fluid Science, 2009
    Co-Authors: Guiyin Fang, Xu Liu
    Abstract:

    An experimental study on operation performance of ice storage air-conditioning system with separate helical heat pipe is conducted in this paper. The experimental system of ice storage air-conditioning system with separate heat pipe is set up. The performance parameters such as the evaporation pressure and the condensation pressure of refrigeration system, the refrigeration capacity and the COP (coefficient of performance) of the system, the IPF (ice packing factor) and the cool storage capacity in the cool storage tank during charging Period, and the cool discharge rate and the cool discharge capacity in the cool storage tank, the outlet water temperature in the cool storage tank and the outlet air temperature in room unit during Discharging Period are investigated. The experimental results show that the ice storage air-conditioning system with separate helical heat pipe can stably work during charging and Discharging Period. This indicates that the ice storage air-conditioning system with separate helical heat pipe is well adapted to cool storage air-conditioning systems in building.

A Barzegar - One of the best experts on this subject based on the ideXlab platform.

  • thermal performance behavior of a domestic hot water solar storage tank during consumption operation
    Energy Conversion and Management, 2011
    Co-Authors: A A Dehghan, A Barzegar
    Abstract:

    Abstract Transient thermal performance behavior of a vertical storage tank of a domestic solar water heating system with a mantle heat exchanger has been investigated numerically in the discharge/consumption mode. It is assumed that the tank is initially stratified during its previous heat storing/charging operation. During the Discharging Period, the city cold water is fed at the bottom of the tank and hot water is extracted from its top outlet port for consumption. Meanwhile, the collector loop is assumed to be active. The conservation equations in the axis-symmetric cylindrical co-ordinate have been used and discretised by employing the finite volume method. The low Reynolds number (LRN) k  −  ω model is utilized for treating turbulence in the fluid. The influence of the tank Grashof number, the incoming cold fluid Reynolds number and the size of the inlet port of the heat storage tank on the transient thermal characteristics of the tank is investigated and discussed. It is found that for higher values of Grashof number, the pre-established thermal stratification is well preserved during the Discharging operation mode. It is also noticed that in order to have a tank with a proper thermal performance and or have least mixing inside the tank during the consumption Period, the tank inflow Reynolds number and or its inflow port diameter should be kept below certain values. In these cases, the storage tank is enabling to provide proper amount of hot water with a proper temperature for consumption purposes.

Luisa F Cabeza - One of the best experts on this subject based on the ideXlab platform.

  • influence of the storage Period between charge and discharge in a latent heat thermal energy storage system working under partial load operating conditions
    Applied Energy, 2019
    Co-Authors: Jaume Gasia, Alvaro De Gracia, Gabriel Zsembinszki, Luisa F Cabeza
    Abstract:

    Abstract The supply intermittency of energy sources like solar energy or industrial waste heat should be properly addressed when studying latent heat thermal energy storage (TES) systems, since it might cause an incomplete melting/solidification of phase change materials (PCM). In the present paper, and experimental study was performed to analyse the storage Period (also known as stand-by Period) in a latent heat TES system working under partial load operating conditions and the effect of its duration on the subsequent Discharging process. In the experimental set-up, 99.5 kg of high density polyethylene (HDPE) was used as PCM in a 0.154 m3 storage tank based on the shell-and-tube heat exchanger concept. Four different percentages of charge were evaluated: 58%, 73%, 83% (partial charge), and 97% (full charge). Each charging level was followed by three different Periods of storage: 25 min, 60 min, and 120 min. The fact of working at different levels of charge caused that in some regions of the TES system the PCM was not completely melted. Thus, at the end of the charging process different levels of thermal homogenisation were observed. However, during the storage Period, the PCM temperature showed a tendency to homogenisation, which was influenced by the energy distribution within the PCM, the heat losses, and the duration of the storage Period. Focusing on the Discharging Period, it was observed that the duration of the storage Period slightly affected the temperature and heat transfer profiles, causing the main differences of performance during the first 30 min of process.

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.