Performance Comparison of Refrigerants HFO1234yf and HFO1234ze in a Vapour Compression Refrigeration System Operating Under Fouled Conditions

In this paper, fouling’s effect on performance of a vapour compression refrigeration system is evaluated by changing evaporator and condenser conductances individually, and simultaneously between 0 to 50% and also by variation in Tin,cond (i.e. coolant inlet temperature of condenser at 35, 37.5 and 40 ℃), for refrigerants HFC134a, HFO1234yf and HFO1234ze, while keeping the Tin,evap (i.e. evaporator air inlet temperature at 0 ℃) and constant \({\upeta }_{{{\text{cp}},{\text{isn}}}}\) (efficiency of compressor, i.e. 65%). A simulation programming is done on EES for computing the results. It is observed that the decrease in COP is more when conductances vary simultaneously in comparison with evaporator and condenser conductances that are varied individually, although fouling of condenser has larger effect on Wcp%, as it increases up to 9.12 and 7.41 for refrigerants HFO1234yf and HFO1234ze, whereas for refrigerant HFC134a, its value increases up to 7.38 with varied coolant inlet temperature of condenser (Tin,cond). It is observed that the second-law efficiency (ƞII) is decreased and HFC134a can be replaced by refrigerants HFO1234yf and HFO1234ze.