A PERFORMANCE ANALYSIS ON A VAPOR COMPRESSION REFRIGERATION SYSTEM GENERATED BY THE REPLACEMENT OF R134a

Abstract

Vapor compression refrigeration is commonly used on board the ships, R134a being one of the most spread refrigerant in this type of systems. In this work, a performance analysis of a vapor compression refrigeration cycle working with R134a and RE170 was carried out. The motivation of this comparison is based on the efforts done to solve the problem of high GWP of R134a, since RE170 shows a significantly lower one.

The study is developed on the analysis of the effect of evaporation pressure on some of important factors which should be considered in the selection of a new refrigerant: evaporation pressure, pressure ratio, Coefficient of Performance, power per ton of refrigeration, volumetric cooling capacity. The evaporation temperature will vary in the range (–20÷+10) ^oC and the condensation temperature is kept constant, at 45^oC. Since cycle performance can be improved by superheating and sub cooling inclusion, these two processes were considered in the cycle.

Comparative results show that RE170 could replace R134a, due to its low evaporation pressure and pressure ratio and also to its better COP and similar volumetric cooling capacity.