Thermodynamic cycle analysis of mobile air conditioning system using hydrofluoroolefin (R1234yf and R1234ze) as an alternative refrigerants to R134a

摘要

This paper presents a thermodynamic cycle analysis of mobile air conditioning system using hydrofluoroolefin (R1234yf and R1234ze) as an alternative replacement for R134a. The analysis evaluates performance on simple VCS under various working conditions (varying condensing temperature and evaporating temperature, subcooling, superheating with and without internal heat exchanger (IHX). R1234ze requires high pressure ratio and high theoretical displacement and for that we need heavier engine and we cannot retrofit with R134a refrigerant so we can select R1234yf for comparison with R134a. The energy performance parameters of R1234yf are close to those obtained with R134a at low condensing temperature and making use of an IHX. Even though the values of performance parameters for R1234yf are smaller than that of R134a, but difference is small so it can be a good alternative to R134a because of its environmental friendly properties with introducing IHX.