Experimental Optimization On The Performance Of A Novel Indirect-expansion Solar-assisted Multifunctional Heat Pump

Solar-assisted heat pump (S AHP) is a combination of the heat pump and solar energy. It not only can meet the demand of space heating, space cooling and hot water, but also can bring out more energy saving operational modes, which result in higher utilization ratio of the heat pump and lower operational cost, therefore the payback time can be shortened greatly. In recent years, the rapid development of the solar assisted multifunctional heat pump (SAMHP) indicates its promising application prospect, but problems in high inicial cost, poor reliability and low year round efficiency are main obstacles to the application of the SAMHP. This paper further studied a novel four-heat-exchanger system with an indirect-expansion heat exchanger by the method of improveing the parts and emploving the new refrigerant. The original experiment setup was modified and a lot of experiments were conducted. The main contents and results of the research are as follows:1. The research history and present status of the solar assisted multifunctional heat pump at home and abroad were reviewed. The characteristics of kinds of SAMHP and internal connections between the cycles were disclosed.2. The indoor heating experiment including the air source space heating mode, solar assisted space heating mode and dual-source space heating mode were conducted. The results show that the coefficient of performance (COP) of the novel IX-SAMHP is greatly benefitted from the increase of the indoor heat exchanger area, the decrease of water pump power and the employing of the new refrigerant. The improvement of COP was23.0%～26.5%for the air source space heating mode, and it was35.3%～38.8%for the solar assisted space heating mode. 3. The heat pump water heating experiment including the air source heat pump water heating mode, solar assisted heat pump water heating mode and dual-source heat pump water heating mode were conducted. The results show that COP of the novel IX-SAMHP is also benefitted from the decrease of water pump power and the employing of the new refrigerant. The reduction of the total power consumption was12.8%～25.2%for air source heat pump water heating mode.4. The coefficient of performance of the dual-source space heating mode closes to that of the air source heating mode, and the total power consumptions of the air source heat pump water heating mode and dual-source heat pump water heating mode are similar.