OPTIMIZATION OF THE PERFORMANCE OF VAPOUR COMPRESSION CYCLE USING LIQUID SUCTION LINE HEAT EXCHANGER

Abstract

One of the most commonly used refrigeration systems is vapour compression refrigeration system. As saving energy remains a challenge, researchers are putting a lot of efforts into finding efficient solution to improve the performance of vapour compression refrigeration systems. Mechanical subcooling and Liquid Suction Line Heat Exchanger (LSLHX) are approaches that have shown to improve the performance of Vapour Compression Cycle (VCC) systems. This experimental study is conducted to achieve two objectives. First objective is to optimize the heat source and heat sink water volumetric flow rate combination that results in the best performance. In order to evaluate the effect of using subcooling cycle and LSLHX cycle, different flow rate combinations are studied and analysed. Then, to optimize the heat source and heat sink water volumetric flow rate combination that outcome in the optimum performance. Second objective is to optimize the system performance through implementing subcooling and LSLHX. At the optimum water flow rates, the basic VCC performance of the designed system showed better performance compared to the published data. The system performance was improved by 10% at the optimum flow rate when solely subcooling was used while deteriorated by 47.5% at full LSLHX.

Keywords

• Coefficient of Performance,Liquid Suction Line Heat Exchanger,Subcooling,Vapour Compression Cycle

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