Abstract:
A solar-air energy dual-source collector evaporator based on flat heat pipe and a new direct expansion heat pump system composed of it are designed,experimental research and analysis are carried out on it.The experiment tests the uniform temperature and thermal conductivity of the flat heat pipe under the condition of low temperature heat extraction by the refrigerant,under the operating conditions of the heat pump the surface temperature distribution of the heat collector evaporator,the photoelectric photothermal performance and the heat pump system under different weather conditions and different operating performan of modes.The results show that the equivalent thermal conductivity of flat heat pipe can reach 6.8×10~5W/(m·℃)at low temperature,the maximum longitudina temperature difference during the operation of the collector evaporator is 3.9℃,In summer,the average COP of solar heating mode in sunny weather is 3.62;the solar-air dual-source mode operating in low-irradiation cloudy days increases the heat collection power per unit area by 18.8% and the system average COP by 5.7% compared with the solar mode.On nights without irradiation,the operating air source mode system average COP is 2.54.