THERMAL PERFORMANCE OF A SOLAR-ASSISTED HEAT PUMP WITH A DOUBLE PASS SOLAR AIR COLLECTOR UNDER CLIMATE CONDITIONS OF IRAQ

The prime aim of the current research is to investigate the thermal performance of the solar-assisted heat pump (SAHP) under the Iraqi climate experimentally and theoretically. In the winter season, the ambient air temperature reduces which causes a reduction in the coefficient of performance (COP) of heat pumps. By utilizing the thermal energy of solar to raise the heat transfer rate of the evaporator, compressor work diminishes and thus the COP of heat pump rises. The experimental setup of SAHP is perform by joining of a solar air heater and an air-to-air heat pump. In this arrangement, the inlet of the air evaporator has been preheated by a solar air heater. The mathematical model based on energy balance was evolved and the performance of this system has been studied over a cold season of Baghdad city (placed in the middle of Iraq). The consequences revealed that the presence of porous media in the lower channel of the absorber plate providing a great surface area for convective heat transfer, therefore, the variation of air temperature and thermal efficiency of the solar air heater are raised. The average thermal efficiency for models (II, III, IV, and V) over the model I (Conventional) are (16.6%, 21.2%, 26.2%, and 30.3%) respectively at mass flow rate 0.02172 kg/s.