Exergic analysis of CO2 trans-critical refrigeration system with and without internal heat exchanger using experimental data.

This paper presents exergetic analysis of a CO2 trans-critical refrigeration system based on experimental data for warm weather condition up to 45oC.Results from configuration with and without internal heat exchanger (IHX) are compared for their performance at two different evaporator temperatures(0oC and -5oC) and gas cooler air flow velocity within range 1 m∙s-1 to 3 m∙s-1. The experimental results demonstrate the relative advantage of use of IHX for high ambient operation. For cycle with IHX, the maximum enhancement in exergy efficiency is found to be 5.05 % at 0oC evaporator temperature while the same is found 4.60 % at -5oC evaporator temperature. Component wise, compressor followed by gas cooler are found to have highest exergy destruction while that in IHXis found to bethe least.