An Experimental Study on The Performance Evaluation of Refrigerant (R134a/R1234yf) In Automobile HVAC System

Abstract

Automobile manufacturers are being compelled to use parts with lower environmental impact due to stricter environmental regulations. One promising alternative is the R1234yf refrigerant, which has a significantly lower Global Warming Potential (GWP) compared to the widely used R134a. In order to assess the performance of these two refrigerants and explore potential improvements for R1234yf, a study was conducted. The research focused on the advantages of incorporating an Internal Heat Exchanger (IHX) into a standard automobile air conditioning system that utilizes R1234yf. The tests were conducted under varying compressor speeds and air temperatures. The findings revealed that using R1234yf with an IHX achieved a comparable cooling capacity (7.25 kW) to that of an R134a system (7.05 kW), even under more challenging conditions. Furthermore, the Coefficient of Performance (COP), which indicates efficiency, was higher for the R1234yf with IHX system (4.3) compared to the baseline R134a system (4.2). Based on this study, it can be inferred that R1234yf, when combined with an IHX and a well-designed evaporator, can be a favourable choice for car air conditioning systems with minimal environmental impact. Switching from R134a to R1234yf provides a solution to address environmental concerns without compromising system performance.