Modeling and performance analysis of rotary compressor considering multi-body coupling and bearing deformation

Rotary compressor, which contains different types of friction pairs, is widely applied in refrigeration equipment. With its development towards high power density and long life, the multi-body interactions and the surface deformation have increasing impacts on the compressor performance. To reveal the working state of the compressor comprehensively and conduct optimal design, a new tribo-dynamic model considering multi-body coupling and bearing deformation is established in this study. Based on the analysis under high ambient pressure, the moving characteristics of the rolling piston and the effects of the crankshaft shoulder profile are presented. It is found that the direction and magnitude of the piston rotation speed highly depend on the working frequency, and an asymmetric crankshaft shoulder profile can dramatically increase the minimum oil film thickness and reduce the wear load. In addition, the impacts of the oil supply structures for the crank, the main bearing and the sub bearing are also given. By comparing different design schemes, the optimized oil supply structures are determined. This work provides a comprehensive analysis method for optimizing the lubrication design of high-performance compressors. •A new tribo-dynamic model of the whole rotary compressor is established.•The effects of multi-body coupling and bearing deformation are considered.•The variation of piston rotation speed highly depends on working frequency.•An asymmetric crankshaft shoulder profile can dramatically reduce wear load.•Compressor performance can be improved with the optimized oil supply structures.