Thermodynamic analysis of trans-critical CO2 refrigeration cycle in Indian context

Abstract

The coefficient of performance for CO2 based trans-critical system is lower at high ambient temperature regions like India due to higher energy required for compression to a high temperature beyond critical point. This paper presents thermodynamic analysis of a basic trans-critical CO2 refrigeration cycle. Further, the basic cycle is modified for two different configurations incorporating parallel compression and inter-cooling. Use of parallel compression and inter-cooling in cycle configuration are two of the most promising cycle modifications for improving the performance of trans-critical CO2 refrigeration systems operating at high ambient temperatures. Simulation results show that parallel compression configuration is more effective. The maximum improvement in COP obtained is about 25% for parallel compression configuration. Also, the operating pressure of gas cooler is found lower for parallel compression configuration.