A review on thermodynamic optimization of irreversible refrigerator and verification with transcritical CO2 system

The transcritical vapor compression refrigeration cycle consists of isothermal heat addition process and isobaric non-isothermal heat rejection process with highly variable heat capacity unlike to the subcritical cycle. Hence, it is quite interesting whether the analysis and optimization results of irreversible Carnot-like refrigerator are applicable for this case. The present study consists of two parts: the detailed review on theoretical analysis and analytical optimizations of irreversible Carnot-like refrigerator with both infinite and finite capacity heat reservoirs, and verification of analytical results with the results obtained from a more elaborate numerical simulation of transcritical CO2 refrigeration system. Considered objective parameters are cooling load or COP and overall heat transfer surface area, and optimizing parameters are cold and hot side working fluid temperatures, ratio of residence times for heat addition and heat rejection, and heat transfer surface area ratio. Reasonably fair agreement has been obtained between analytical and numerical model predictions.
Keywords:

Thermodynamics,