Single screw compressor, Stress analysis, Mode analysis, Vibration, Meshing pair
The single screw compressor(SSC) is widely applied to air compression, refrigeration, petrochemical industry, waste heat recovery, etc. Among SSCs, the respective strength and stiffness of the casing, screw rotor and gaterotor, where relative motions occur, play a key role on the machine running and clearance fit. Dynamic properties of the meshing pair directly affect the SSC’s vibration, as well as gaterotor’s wear-out failure. In this thesis, the strength, stiffness and dynamic characteristics of the meshing pair under different operation conditions or with components made of different materials were analyzed. Analytical method and FEM were combined to calculate and analyze the issues above. Main contents and conclusions are as follows: Stress and deformation analysis of key components were implemented by ANSYS Workbench. The results show that both the maximum stress of the casing and the deformation of the gaterotor are basically linear to the discharge pressure. The first six natural frequencies and the corresponding vibration modes of the screw rotor and gaterotor were obtained to analyze and predict their respective vibration properties. It turned out that natural properties of the screw rotor change little on account of rotation speed and damping. Neither the screw rotor nor the gaterotor would resonate. Some exploratory work about the coupling interaction between gaterotor and its support was done. It is concluded that the gaterotor would suffer the support’s collision excitations consequently.