Energetic and Exergetic Based Comparison Multiple Evaporators with Compound Compression and Flash Intercooler with Individual or Multiple Throttle Valves

Abstract

The utility of second law analysis on vapour compression refrigeration systems is well defined because it gives the idea for improvements in efficiency due to modifications in existing design in terms of reducing exergy destructions in the components. Due to effect of global warming and ozone depletion the comparison and impact of environmental friendly refrigerants (R507a, R410a, R290, R600, R600a, R1234yf, R404a, R125, R717, R152a and R407C) on multiple evaporators at different temperature with compound compression and flash intercooler with individual and multiple throttle valves is important for calculating first law and second law performance on the basis of energetic and exergetic approach. Comparison was done for multiple evaporators with compound compression and flash intercooler with individual throttle valves (system-1) and multiple evaporators with compound compression and flash intercooler with multiple throttle valves (system-2) in terms of coefficient of performance, rational efficiency and total system defect. It was observed that for all considered refrigerants second law first law efficiency of system-1 is lower than sytem-2 conversely system defect of system-1 is higher than system-2.In terms of energetic efficiency, rational efficiency and system defect for both systemsR407C shows minimum performance and performances of R600, R152a and R717 better with comparison of other selected refrigerants for system-1 and system-2. But R600 is highly inflammable and R717 is toxic in nature and restricted to limited applications, so R152a is suggested for both systems.