HCFC22-BASED VAPOUR ABSORPTION REFRIGERATION SYSTEMS. PART Ⅱ: INFLUENCE OF COMPONENT EFFECTIVENESS

摘要

A thermodynamic analysis was performed on a single-stage vapour absorption refrigeration system (VARS) operating with monochlorodifluouromethane (HCFC22) as a refrigerant and dimethylether of tetraethyleneglycol (DMETEG) or dimethyl acitamide (DMA) as a working fluid. Influence of solution heat exchanger effectiveness (E_h) and mass transfer effectivenesses of absorber (E_a) and generator (E_g) on the performance of VARS were studied. The variations in heat quantities at solution heat exchanger, generator and absorber as well as performance characteristics, namely CR, COP_(th) and second law efficiency (ε) at various operating temperatures are reported. As expected, low CR and high COP_(th) and ε can be obtained at high values of E_h, E_a and E_g. The effects of E_h on the performance is more pronounced when compared to that of E_a and E_g. Also, the change in the circulation ratio (CR) due to a given change in E_a is higher than that due to the same change in E_g. CR is not a function of E_h. A comparison of the influence of E_h, E_a, and E_g on the VARS performance for HCFC22-DMA and HCFC22-DMETEG pairs was made.