Computational fluid dynamics analysis on oil pumping system for rolling piston compressors

A numerical simulation was done on the oil pumping system of a rolling piston compressor by adopting the computational fluid dynamics (CFD) software. A physical model of the oil pumping system was established, and a general method of setting boundaries and calculating the leakage rates through the roller end significant was presented. The dynamic process of the oil pumping system was translated into static issue. In addition, the measurement of the main bearing oil flow rates was conducted to validate the rationality of the oil pumping system model. The effects of the operating condition of the compressor, the oil level height of the oil sump in the shell and the main design parameters of the oil pumping system of the compressor on the oil pumping rates were analyzed by the CFD simulation. The results show that the oil leakage rate through the roller end clearances depends largely on the operating condition of the compressor. The oil level height of the oil sump has a significant influence on the oil pumping rate. With the given operating condition and oil level height, the main bearing oil flow rate is determined by the spiral groove shape and inclination of the main bearing.