Energetic and exergetic performance comparison of cascade refrigeration system using R170-R161 and R41-R404A as refrigerant pairs

A numerical study of cascade refrigeration system using two different refrigerant pairs, namely, R41-R404A and R170-R161 working under the same operating conditions has been presented in this paper. A computer code has been developed in Engineering Equation Solver software using the basic energy and exergy equations of cascade refrigeration system. Values of some of the important input parameters for the analysis have been taken from the literatures to carry out this simulation work. The effect of evaporator temperature on the basic performance parameters, such as COP, compressor power, total exergy destruction, exergetic efficiency has been computed. The analysis of the predicted results shows that for each evaporator temperature, an optimal point exists where the system shows maximum performance. An effective reduction of compressor work and total exergy loss is observed with R170-R161 system than those of the R41-R404A system. This eventually results in higher optimal COP as well as exergetic efficiency for R170-R161 system compared to R41-R404A system.