"AN ATTEMPT TO IMPROVE ENERGY EFFICIENCY OF VAPOUR COMPRESSION REFRIGERATION ON SYSTEMS WORKING WITH R134a"

Abstract

"Refrigeration is an industry of high importance in our modern times. It plays also a key role in maritime transport of perishables, where vapour compression refrigeration systems are dominant. These energy systems are indispensable, but they should be wise exploited because their high energy necessity. One of the frequent refrigerant chemical adopted in this system is the hydrofluorocarbon R134a. This refrigerant came to substitute traditional refrigerants, such as chlorofluorocarbons or hydro chlorofluorocarbons – substances being under environmental regulations. In this study, it is approached a single stage vapour compression refrigeration system working with R134a. The aim is to find the conditions in which this system is more energy efficient. In this respect, based on the laws of thermodynamics, are obtained information on Coefficient of Performance and energy destruction trends – when the evaporator temperature increases. Our results indicate that, although the analysis based on the first law of thermodynamics reveals that the performance of the system is higher for high evaporator temperatures, the energy destructions in this system increase together with the evaporator temperature increase. "