Static and Modal Analysis of a Main Rotor in Single Screw Compressors

The CP-type single screw compressors start to be widely used in refrigeration and heat pump system due to its higher load capacities and more flexible control system compared with a twin screw compressor. The strength and stiffness design are the foundation to promote the operational reliability of single screw compressor. The aim of this study was to estimate the main rotor’s performance by dealing with structural and modal analysis of a main rotor made of two different materials (HT200 and QT400). In this paper we firstly obtain three-dimensional main rotor by Pro/Engineer and then imported it into ANSYS software. Based on the structural analysis, the maximal stress and deformation of the groove wall are obtained with changes of the outlet pressure, and the static analysis indicates that the deformation of the groove wall is a major factor we need to consider when design single screw compressors. By modal analysis, the frequency and deformation of the main rotor are presented, and the modal analysis demonstrates that the main rotor can work at the designed frequency and the resonance phenomenon does not happen. The results acquired here may have practical applications in the design of CP-type single screw compressors.