Simulation Of Phase Change Storage Refrigerant Direct Heat Pump Radiation System For Temporary House

Energy consumption is growing day by day,the problem of power shortage is serious,and the problem of environment and energy shortage is aggravated.Temporary housing,such as container housing,has attracted more and more attention and use due to its advantages of low carbon and low cost.However,at the present stage,traditional heating methods are mostly used for temporary housing.For some extreme environments,such as low heating efficiency and high energy consumption,traditional heating methods are not conducive to energy conservation and emission reduction and the realization of the "double carbon" goal due to the disadvantages of low heating efficiency and high energy consumption.The Olympic venues are located in a cold alpine region,in an extreme environment.According to the special geographical environment and heating requirements of the Winter Olympics,a new heating system is proposed,which combines the refrigerant direct heat pump technology and phase change energy.An experimental platform of the temporary room was built,which adopted the refrigerant direct heat pump radiant heating system(without phase change material layer).Then,the room model corresponding to the experimental platform was established in Fluent.By comparing the experimental data and simulation data under the same working condition,the data included the room temperature,the inner surface temperature of the envelope structure,the heating time of the system,etc.The accuracy of the room model is verified,which provides a basis for the subsequent simulation research.A temporary room model of direct heat pump radiant heating system with phase change energy storage coolant was established to simulate the heat release process of phase change materials in the temporary room under the actual Winter Olympic weather conditions.Through comparative analysis of the simulation results,phase change materials with appropriate parameters were selected and the optimal design scheme of phase change materials meeting the requirements was determined.It includes determining the PCM layer filling scheme and determining the corresponding optimal PCM layer thickness.Then,by simulating the heating process of different average heating temperature conditions,the influence of heating temperature on the inner surface temperature of the wall,the heat storage time and the thermal environment of the room is analyzed.By controlling the opening and closing of heat supply,the temperature of the room is not less than 16℃ but not more than 20℃,and the whole day working condition simulation(phase change material heat release process and heat pump heating,phase change material heat storage process)is carried out.The overall thermal comfort of the room is analyzed by using the operating temperature,the predicted average evaluation and the predicted percentage of dissatisfaction.Based on the internal surface temperature and vertical temperature difference of heating wall,the thermal comfort of local room is analyzed.It is found that the scheme of heating one hour in advance and adopting the temperature control method can make the temperature field of the room uniform,and the local thermal comfort and the overall thermal comfort are kept in a good range during the whole heating process.