Abstract: Aiming at the leakage problem in the compression chambers of scroll compressor, the internal flow field characteristics of scroll compressor under different radial clearance conditions were studied. Firstly, the real size fluid domain model of a scroll compressor was established, and the flow law in the working chamber of the scroll compressor was analyzed. Then, the structured grid in the fluid domain was generated by using PumpLinx software, and the internal flow field under different radial clearance conditions was numerically simulated. Finally, the transient and average effects of radial clearance on pressure, inlet and outlet mass flow, shaft power of moving scroll part were studied.The results show that the pressure distribution in the same compression chamber is uniform, but the temperature distribution is uneven. The larger the radial clearance is, the more obvious the temperature heterogeneity is. When the radial clearance increases from 0.02mm to 0.08mm, the average mass flow at the inlet and outlet can decrease, the volumetric efficiency can decrease from 92.7% to 67.9%, and the average shaft power of the moving scroll disk can increase by 18.7%. Therefore, controlling the radial clearance is of great significance to improve the nonuniformity of force on the moving scroll, improve the volumetric efficiency and reduce the power consumption.

Key words:  scroll compressor;radial clearance;leakage loss;internal flow field characteristics;fluid domain model;numerical simulation