Numerical simulation method of rotor structure characteristics of twin-screw compressor rotor

LI Tuo-lei, WANG Jun-li, LEI Shuai, REN Zhi-gui, LI Qing-qing, LU Zheng-wu
(Mechanical Engineering College, Shanxi University of Technology, Hanzhong 723000, China)

Abstract: Aiming at the problem of rotor structure characteristics in the working process of twinscrew compressor, a coupling simulation method of stress and deformation of screw rotor was designed, and the influence of different exhaust pressure and different rotating speed on rotor stress and deformation was studied. Based on finite volume method, the pressure field generated during the compressor operation was solved. Through the numerical interpolation technique, the aerodynamic load was applied to the structure grid of the rotor as the external load, and the real force model of rotor was established. The static equilibrium equation of the rotor structure was solved in the real stress model, and the displacement field and stress distribution of the rotor were obtained, and the research method in this paper was verified by “L-shaped large diameter buried pipeline”. The results indicate that the pressure field generated during the compressor operation has a great influence on the maximum deformation and maximum stress of the screw rotor, and when the speed/exhaust pressure is constant, the selection of appropriate exhaust pressure/rotational speed can effectively reduce the maximum deformation and maximum stress of the rotor. The research can provide some theoretical reference for the structure design and optimization of compressor.
Key words: compressor; finite volume method; numerical interpolation; aerodynamic load；static equilibrium equation