OPTIMIZATION OF A DOUBLE EFFECT LIBR-H20 ABSORPTION SYSTEM

Abstract

A computer program is developed to optimize a double-effect LiBr-H20 absorption refn·geration system. Optimum coefficient of performance (COP) of the refrigeration system is sought for a frxed cooling load capacity of a system and fzxed upper cycle pressure (pressure of Generator 1) and lower cycle pressure (pressure of EvaporaJor!Absorber), For any frxed upper cycle pressure and lower cycle pressure, the intermediate pressure (pressure of Condenser/ Generator 2) of the system is varied until the optimum COP is obtained.
The effect of increasing of the temperature of Generator 1 on the COP of the !lystem is also analysed. Pure water vapor is considered to be
generated in both geTierators at the respective prevailing pressure and temperature combinations. Specific enthalpies of pure water vapor at outlet from the respective generators and the condensate water leaving the Condenser are automatically determined by the developed programme at the prevailing satur"'ation temperatures. Concentrations
at all state points in the cycle are also obtained from the programme at the respective state point pressure and temperature values. In the analysis, steady-state conditions and no pressure losses are assumed. The effect of the effectiveness of the heat exchangers on the COP of the system are olso anolysed using the developed program.