Estimation of leakage through radial clearance during compression process of a rolling piston rotary compressor

The leakage characteristics during the compression process in a rolling piston rotary compressor were investigated in this research. The thermodynamic conditions and geometric features during the compression process were determined from the results of a numerical compressor simulation. Refrigerant R410a and lubricant oil PVE-68 were used as working fluids. Leakage models with and without consideration of the lubricant oil effect were used to examine leakage characteristics through the radial clearance. A model for pure refrigerant that included the operating conditions and geometric characteristics of a compressor was developed using the verified results of a CFD (Computational fluid dynamics) simulation. The area ratios for both the refrigerant and lubricant oil at the radial clearance was obtained by numerical analysis during the compression process of the rolling piston rotary compressor. The results showed that the cross sectional area at the radial clearance would be charged with the pure refrigerant up to a maximum of 81.2 % during the compression process.