Five performance indicators for a universal generalized irreversible steady flow cycle including seven specific refrigeration cycles

Cycle model extension and universalization with different performance indicators and with all of loss items is an important topic in finite time thermodynamics (FTT) studies. A model of universal generalized irreversible steady flow refrigeration cycle including two irreversible endothermic, two irreversible exothermic and two irreversible adiabatic processes with three loss items of heat resistance, thermal leakage and internal irreversibility effect is established by using FTT. Expressions for five performance indicators, including cooling load, COP, exergetic loss rate, exergetic output rate and ecological function of the universal cycle model are derived. Expressions for five performance indicators obtained include those of seven specific refrigeration cycles, that is, Diesel, Brayton, Otto, Atkinson, Miller, Dual and Carnot refrigeration cycles, with various loss combinations of three loss items. Performance indicator analyses and optimizations of the universal cycle model are performed, and effects of cycle processes and loss items on the five performance indicators of the universal cycle are illustrated by using numerical examples.