ENERGY ANALYSIS OF A VAPOR COMPRESSION SYSTEM CASCADED WITH AMMONIA–WATER ABSORPTION SYSTEM
The first law analysis of a vapor compression–vapor absorption (VC–VA) cascade system is carried out for a wide range of cooling capacity. While ammonia–water is the working pair in VA section, R407C is used in VC section. The influences of change in cooling capacity, superheating and subcooling in the condenser, temperature in the generator, degree of overlap in cascade condenser, size of the heat exchangers etc. on the system performance are investigated. It is concluded that the COP of the VC section of the cascade system could be improved by 146% and the electricity consumption could be reduced by 64% compared to an equivalent VC unit. Separately the results showed the considerable increase in the generator heat when cooling capacity was increased from 83.33 kW. The COP of the cascade system at high cooling capacity is strongly dependent on the performance of condenser.