Cycle analysis of air-cooled absorption chiller using a new working solution

Abstract

A cycle analysis was achieved to predict the characteristics by comprehensive modelling and simulation of an air-cooled, double-effect absorption system using the new H 2O/LiBr+HO(CH 2) 3OH solution. The simulation results showed that the new working fluid may provide the crystallisation limit 8% higher than the conventional H 2O/LiBr solution. With a crystallisation margin of 3 wt%, the optimal solution distribution ratio was found to be in the range of 37–39%. Variation of cooling air inlet temperature had a sensitive effect on the cooling coefficient of performance (COP) and corrosion problem. The simulation of heat exchangers with UA value revealed that the absorber and evaporator were relatively important for an air-cooled system compared with the condenser and the low temperature generator. The effects of cooling air flow rate, circulation weak solution flow rate and chilled water inlet temperature were also examined. The new working fluid may provide a COP approximately 3% higher than the conventional H 2O/LiBr solution in normal conditions of circulation weak solution.