Performance optimization of three-heat-source irreversible refrigerators based on a new thermo-ecological criterion

This paper presents an optimization study of an irreversible refrigeration absorption system based on a new thermo-ecological criterion. The considered objective function is the ecological coefficient of performance (ECOP). It takes into account the first and second law of thermodynamics and is defined as the cooling load per unit loss rate of availability. The ecological coefficient of performance has been expressed and maximized according to the temperatures of the working fluid in the main components of the system. The corresponding optimal temperatures and other optimum performance parameters have been derived analytically, and the effects of the internal irreversibility, the heat leakage coefficient and the source temperature ratio on the global and optimal performances are discussed. The results show that the maximum coefficient of performance (COP) and ecological coefficient of performance (ECOP) occurs for the same operating conditions.