Dynamical modeling and thermo-economic optimization of a cold room assisted vapor-compression refrigeration cycle

A cold room assisted vapor-compression refrigeration cycle is dynamically modeled in a year and optimized. Total annual cost (TACO) and coefficient of performance (COP) are selected as two objective functions. Both cold room and refrigeration cycle parameters are considered as design variables. Moreover, three working fluids included R22, R134a and R407c are examined. The optimum Pareto front reveals that unlike the thermal system such as heat exchanger and power plant, the objective functions are not conflicted in the optimum situation. The optimum solutions show that R407c is the best refrigerant in both thermodynamics and economics viewpoints with 9148.2 $/year as total annual cost and 6.12 for COP. The optimum result of R407c showed that the total annual cost improved by 50.74% and 8.68% in comparison with R134a and R22, respectively. Furthermore, COP improved 9.97% and 13.72% in R407c compared with R134a and R22, respectively.