Dynamic Mesh Technology for the Simulation Study of Single Screw Expander

摘要

Computational fluid dynamics (CFD) methods have been widely used in simulating internal flow of rotary positive displacement type compressors and expanders, especially for twin screw, scroll and rolling piston machines. But it is still lack of CFD research on single screw compressors and expanders due to the difficulty of spacial screw curved surface of single screw structure and the working principle of symmetrical intake and six screw groove simultaneous discharge in single screw machines. In order to investigate internal unsteady flow characteristics and improve the performance of single screw machines, CFD analysis in a single screw expander has been given in this paper. The STAR-CCM+ commercial software and its dynamic mesh technology have been applied to simulate the single screw expanders. The air has been selected as the working fluid of single screw expander and the ideal gas equation of state has been used to analyze its properties. The simulation results show that the periodic variation in pressure and velocity of single screw expander have been carried out, the pressure cloudy chart of internal flow field of single screw expander has been obtained.