Abstract
This study used Computational Fluid Dynamics (CFD) to simulate and analyze the working fluid in magnetic centrifugal refrigerant compressors using R-134a to mixed refrigerant: R-513A and HFO (Hydrofluoroolefins) Hydrofluoroolefin refrigerant: R-1234yf, and the impact on integrated part-load performance, Integrated Part Load Value (IPLV) and internal flow field. This study used a single-stage 280 USRT maglev centrifugal refrigerant compressor as a simulation model. Three different refrigerants were used: R-134a, R-513A, and R-1234yf, as presented in the National Institute of Standards and Technology (NIST) real gas database. The refrigerant was used to set the IPLV working conditions and change the compressor speed and mass flow rate to simulate the compressor’s characteristic curve after replacing the refrigerant. The compressor working conditions were the fixed refrigeration cycle condensation and evaporation following the same capacity standards. This study used the CFD software by Ansys software company to simulate the flow field. The k-omega turbulence software was used to model the turbulence. The results show that the maglev centrifugal refrigerant compressor efficiency dropped significantly when the refrigerant was directly replaced. Based on R-134a, the full load efficiency of R-1234yf dropped 13.21%, the full load efficiency of R-513A dropped 9.97%, and the partial load efficiency was similar to R-134a.