Dynamic Simulation Analysis On Rotor System Of Scroll Compressor

Scroll compressor is a widely used fluid machine.It has been widely used in refrigeration and air-conditioning,various gas compression,booster pumps and other fields.Under various working conditions,it is very important to guarantee the good dynamic characteristics of the scroll compressor rotor system.The dynamic characteristics of parts will affect the reliability of the scroll compressor operation.In this paper,the rotor system of scroll compressor was taken as the research object.Based on the virtual prototype technology,the rotor system model considerin g the joint clearances and the flexibility of the parts was established by means of 3D modeling software Solidworks,dynamics simulation software ADAMS and finite element analysis software ANSYS.Dynamics of the rotor system was simulated considering the overturn of orbiting scroll.According to the simulation results,the finite element analysis of the related parts was carried out,and the dynamic characteristics of the rotor system were deeply studied in order to provide analytical method and theoretical guidance for design and dynamic behavior prediction of rotor system.First of all,this paper introduced the basic theory of scroll compressor.According to the geometric theory of scroll compressor,the rotor system and the orbiting scroll were carried out a force analysis and dynamic models were established.The numerical analysis method was used to calculate gas force and torque on the dynamic scroll.The magnitude of the gas force and torque var y with the rotation angle of the main shaft.A vector model and a collision force model at the joint clearance were established and embedded in the rotor system dynamics model.With the help of Solidworks software,the 3D solid model of the rotor system were established.Secondly,according to the multi-body dynamics research method and virtual prototyping technology,the dynamic model of the rotor system with joint clearances was established and simulated by ADAMS software.The dynamics simulation analysis of the rotor system was carried out considering the overturn of orbiting scroll and the joint clearances.The variation laws of the dynamic characteristics of driving bearing with different joint clearances were obtained at fixed speed.The results show that under the overturning of the orbiting scroll,the clearance value has no significant influence on the displacement and speed of driving bearing,and has a great influence on the acceleration and the collision force of driving bearing.With the clearance increasing,the vibration frequency and the amplitude of the acceleration and collision force are lager,which causes a larger deviation compare with ideal mechanism.The bearing is eccentrically worn in the area of 19.11° after the discharge angleFinally,the ADAMS software and ANSYS software were used to simulate the multi-flexible dynamics of the rotor system.Using ANSYS to establish the MNF file of the driving bearing,a rigid-flexible coupling model of the rotor system considering the elastic deformation of the drive bearing and the joint clearances was established in ADAMS.The dynamics simulation analysis was carried out under the overturning of the orbiting scroll and fixed clearance,and the simulation results were used as the boundary conditions.The boundary conditions were analyzed by finite element analysis of the eccentric worn area of the drive bearing.The results show that under the overturning of the orbiting scroll,flexibility of the bearing has little effect on the displacement and velocity of the bearing,and has a great in fluence on the acceleration and the collision force.The coupling of flexible deformation and the clearances exacerbate the collision force between the bearing and the crank pin.The acceleration curve to fluctuate around the ideal curve at a high frequenc y,which increases the eccentric worn area,and the maximum stress of the needle roller occurs at 2/7 of the length of the needle roller.