Keywords: absorption refrigeration systems, single-effect, double-effect, half-effect, absorber effectiveness, mass transfer, R134a-DMAC, thermodynamics, absorption cooling
Influence of absorber mass transfer effectiveness on performance of R 134a-DMAC based single, double and half-effect absorption cooling systems
A thermodynamic analysis was performed on half-effect, single-effect and double-effect VARS with R-134a-DMAC as working fluid to study the influence of absorber mass transfer effectiveness (Ea) at various generator and evaporator temperatures on performance parameters namely circulation ratio, Coefficient of performance (Cop) and second law efficiency. The variations in heat quantities of absorber and generator were also studied, using a computer simulation which revealed that the single, double and half effect system can efficiently be applied, where the heat source is available at 80, 130 and 55°C, respectively. Double-effect system yielded maximum percentage increase in Cop, when Ea varied from 0.5 to 1. The thermo-dynamic penalty of half-effect system is its high rate heat rejection at the absorbers.