Performance comparison of two absorption-compression hybrid refrigeration systems using R1234yf/ionic liquid as working pair

R1234yf (2,3,3,3-tetrafluoroprop-1-ene)/ionic liquid is a kind of environment-friendly working pair, which can overcome the disadvantages of H2O/LiBr and NH3/H2O. In this work, three new working pairs R1234yf/[HMIM] [TfO], R1234yf/[HMIM] [PF6], R1234yf/[HMIM] [BF4] were proposed and new solubility data for them were determined. Two new absorption-compression hybrid refrigeration systems were proposed to improve the cooling performances of the single-effect absorption refrigeration system using R1234yf/[HMIM][TfO], R1234yf/[HMIM] [PF6] and R1234yf/[HMIM] [BF4] as working pair. The effects of compressor position, compression ratio (r), generation temperature (T-g), evaporation temperature (T-e), condensation temperature (T-c) and absorption temperature (T-a) on the coefficient of performance (COP) and circulation ratio (f) were analyzed. Comparison result shows that the two systems can effectively improve the cooling performance of the single effect absorption refrigeration system including increasing COP, reducing the heat load of condenser and f, and enlarge the operation range of T-g, T-a, and T-e. Putting compressor between evaporator and absorber is a better choice than putting it between generator and condenser. R1234yf/[HMIM] [TfO] shows better cooling performance than R1234yf/[HMIM] [PF6] and R1234yf/[HMIM][BF4] due to its favorable thermophysical properties.