Performance analysis of R1234yf/ionic liquid working fluids for single-effect and compression-assisted absorption refrigeration systems

Due to the disadvantages of conventional working pairs (NH₃/H₂O and H₂O/LiBr) in the absorption-refrigeration cycles, 2,3,3,3-Tetrafluoroprop-1-ene(R1234yf)/ionic liquid (IL), which possessed of remarkable properties, has received more and more attention. In this work, the thermodynamic performance of single-effect and compression-assisted absorption refrigeration cycles were analyzed using R1234yf as refrigerant and ILs (including [emim][BF₄], [hmim][BF₄], [omim][BF₄], [hmim][Tf2N], [hmim][PF6] and [hmim][TfO]) as absorbent, the thermodynamic properties of working pairs was estimated by the NRTL model. The effects of generation, evaporation, condensation and absorption temperature as well as compression ratio on the cooling performance and circulation ratio were studied in various working conditions. Compared to the single-effect cycle, the compression-assisted cycle effectively improves the cooling performance, reduces the circulation ratio and extends the operation range of generation, evaporation and absorption temperatures. At the same working condition, [hmim][Tf₂N] performs the best while [emim][BF₄] has the lowest COP, the cooling performance of [hmim][BF₄], [omim][BF₄], [hmim][TfO] and [hmim][PF₆] is similar.