Abstract: On the basis of the endoreversible refrigeration cycle model which considers only the irreversibility of heat resistance between working fluid and heat reservoirs, this paper presents a new irreversible refrigerator model by add a constant parameter to represent the loss of heat leak, and a constant coefficient to represent the internal irreversibilities, such as friction, turbulence, non-equilibrium and so on. The relation between the optimal rate of refrigeration(ROR) and the coefficient of performance (COP) of the model is derived, the maximum COP and the corresponding ROR are obtained, and the effects of heat resistance, heat leak and internal irreversibility on the performance of the refrigeration plant are analysed.

Key words: finite-time thermodynamics, irreversible refrigerator, performance optimization