Theoretical Analysis And Experimental Study On Heat Pump System With Flash-Tank Coupled With Scroll Compressor

Economizer cycle can effectively improve the main deficiencies of conventional air-source heat pump such as low efficiency and poor reliability when running in conditions of low ambient temperature by improving its internal compression process. In this paper, based on the status in quo of quasi-two stage heat pump system with scroll compressor, the heat pump system with flash-tank coupled with scroll compressor is comprehensively analyzed, and the experimental investigation for the prototype is presented. In this paper, firstly, the heat pump system with flash-tank coupled with scroll compressor and its working principle were introduced in detail. Considering a supplementary inlet added, thus a process of supplementing-compressing was added. The process of supplementing-compressing was unsteady-flow with multivariate compression process that quality flow of working medium and volume of working chamber continuously changed. Based on this characteristic, the mathematic model was set up, and the main performances were calculated by emulating and simulating for heat pump system with flash-tank coupled with scroll compressor under low temperature conditions, and with aid of the results calculated, the optimal switching-point between one-stage system and quasi two-stage system was found. Additionally, when supplementary inlet was added on the scroll compressor, factors affecting electric power input became complex, therefore, the coefficients such as electric efficiency had not met to the empirical formula, quantity of supplement and the position of supplementary inlet all affected these coefficients. In this paper, the correlation of electric efficiency was fit by least square method on the basis of measured data of the heat pump prototype, which can supply references for theoretical study of economizer in the future. Based on theoretical analysis, the experimental project of heat pump system with flash-tank economizer coupled with scroll compressor was developed, and the prototype was comprehensively experimented and its behavior was analyzed by the...