Analysis of an R744 typical booster configuration, an R744 parallel-compressor booster configuration and an R717/R744 cascade refrigeration system for retail food applications. Part 1: Thermodynamic analysis

In this paper, the performances of a typical R744 booster configuration, a R744 parallel-compressor booster refrigeration system, and a R717/R744 cascade system configuration are presented based on the 1st and 2nd law of thermodynamics, for food retail applications. The results for a supermarket application with a total 145 kW cooling capacity show that the typical booster system and parallel-compressor booster system have better performances than the cascade system. However, for convenience store applications with 30 kW total cooling capacity the cascade system shows better performance beyond 26 degrees C ambient temperature which limits the applications of the cascade system for low capacity systems and the parallel refrigeration system solution appears to be a better option. In addition, the most critical components of each system based on the 2nd law are identified in this paper. (C) 2019 The Authors. Published by Elsevier Ltd.