EXERGETIC ANALYSIS OF CO_2 TRANS-CRITICAL REFRIGERATION SYSTEM WITH AND WITHOUT INTERNAL HEAT EXCHANGER USING EXPERIMENTAL DATA

摘要

This paper presents exergetic analysis of a CO_2 trans-critical refrigeration system based on experimental data for warm weather condition up to 45°C. Results from configuration with and without internal heat exchanger (IHX) are compared for their performance at two different evaporator temperatures(0°C and -5°C) 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 0°C evaporator temperature while the same is found 4.60% at -5°C evaporator temperature. Component wise, compressor followed by gas cooler are found to have highest exergy destruction while that in IHXis found to bethe least.