Numerical analysis and optimization study of photovoltaic/thermal-air source evaporator based on micro heat pipe arrays

Photovoltaic/thermal-air source evaporator (PV/TAE) based on micro heat pipe arrays can extract heat from the waste heat of photovoltaic (PV) module and air, which serve as a low -temperature heat source for heat pump system, achieving complementary and efficient utilization of solar and air energy. In this study, a heat transfer model for the coupling of dual -source complementary heat collection and PV power generation in PV/TAE and a simulation model for the dual heat source direct -expansion heat pump system were established, and the accuracy of models were verified. The effects of solar irradiation, ambient temperature, and heat collection wind speed of air side on the performance of PV/TAE were analyzed. The structural parameters of finned air ducts and refrigerant channels were optimized. Results showed that the thermal performance of the optimized PV/TAE was remarkably improved. Under a solar irradiation of 700 W/m(2) and an ambient temperature of 32 C, the heat collection power per unit area increased by 26.63 % (i.e., from 614.49 W/m(2) to 778.13 W/m(2)), and the heat collection efficiency increased by 25.76 %. The COPh was improved to some extent, increasing by 7.94 % (i.e., from 4.28 to 4.62). The optimized PV/TAE improved the utilization capacity for solar and air energy.