Performance Optimization Of A Photovoltaic Loop Heat Pipe Solar Assisted Air Source Heat Pump Water Heating System

In order to reduce power consumption in the domestic hot water sector,the operating performance of a novel photovoltaic loop heat pipe/solar assisted air source heat pump?PV-LHP/SA-ASHP?water heating system is optimized in this paper.The main contents of this manuscript are as follows:Based on the mathematical model of photovoltaic loop heat pipe mode and heat pump mode that built by previous researchers,the influence of PV module coverage fraction,water tank volume and operation strategy on the operating performance of the target system were studied successively.The results indicate that,by increasing the PV coverage fraction on the absorption panel surface in reason,reducing water tank volume properly and starting the heat pump loop earlier under poor operating circumstance,the solar heating fraction could be improved by 7%,while the system's power consumption could be reduced by 55.7%,in other word,the energy conservation performance of the studied system could be significantly improved.Based on the optimal operation structural parameters and optimal strategy,the operating performance of the target system,solar assisted air source heat pump water heating system and traditional air source heat pump water heating system are studied and compared to predict the feasibility of applying the target system in cold climatic region.According to the results,when replacing the last two systems by the target system to operate in Beijing,the power consumption could be reduced by 72%to 79%,on the other hand,the CO₂ emissions could be decreased by 65%to 72%.In terms of economic performance,the life cycle cost could be saved by 59%to 66%.Therefore,at foreseeable future,it would be possible for the target system to apply in cold climatic zone.As operating parameters changes,it is possible for the PV-LHP to behave in poor.In this case,specific response measures are proposed,in other word,utilize the heat of exhaust air from air-conditioned rooms to regulate the temperature of absorption panel and PV module,thus improving the performance of the target system.Based on the law of mass,momentum and energy conservation,the mathematical model of the PV/T collector was established by ANSYS Fluent software,so that the impact of response measures on the operation the PV-LHP could be studied in numerical method.According to the results,with proper response measures employed,the solar photovoltaic efficiency of PV-LHP mode could be significantly improved,with the power generation be improved by 7.8%to11.5%during responding period in summer.In winter condition,the heat absorption of cooling water within half an hour of sunrise could be improved by 375.7%.