The Research On Stress And Deformation Simulation Analysis Of Variable Pitch Scroll Under Thermo-mechanical Loading

Scroll compressor,as an efficient and energy-saving volumetric fluid machinery,is widely used in energy,chemical,medical and health fields.With the rapid development of China ’s industry,industrial equipment is constantly developing under extreme conditions such as high temperature,high pressure and high speed,which makes the working environment of scroll compressor more complex and puts forward higher requirements for the reliable operation of scroll compressor.The correct meshing of the fixed and orbiting scroll plates is the key to the gas force lifting and safe and reliable operation of the scroll compressor.In the working process of the compressor,the scroll is subjected to various load forces,including temperature load,gas force,centrifugal force and friction force.The internal leakage and central tooth head adhesion caused by the deformation of the scroll tooth under the load force directly affect the reliability and performance index of the scroll compressor.Therefore,it is of great significance to study the stress and deformation of the scroll tooth to improve the performance of the compressor.The variable tooth height structure used in the development of scroll compressor to high pressure ratio is studied by combining theoretical calculation and numerical simulation,the mathematical model and three-dimensional model of the variable-toothheight scroll plate are established,and the stress and deformation laws of the variabletooth-height scroll plate under the coupling of nonlinear temperature load,pressure load and thermal-force load are obtained;Through the analysis and comparison of the stress and deformation laws of three common materials,the scroll plate material with excellent performance was determined.The details are as follows :(1)Base on that analysis of the structure and working principle of the scroll compressor,the mathematical model and structure size of the scroll compressor are determine.On the basis of using Solidworks software to establish three-dimensional model of fixed tooth height scroll,based on the suction pressure and exhaust pressure,the size and mutation position of the tooth top and bottom are determined,the mathematical model and three-dimensional model of variable tooth height scroll are established.(2)With the help of the established three-dimensional model of the scroll,the variation of the volume of each working chamber of the variable and fixed tooth height structure with the spindle rotation angle and the variation of the gas force under the same suction pressure are solved and compared.The overturning moment before and after the inner depth of the variable tooth high orbiting scroll drive bearing is compared.(3)With the help of Ansys software,the stress and deformation of fixed and orbiting scroll plates and assemblies with variable and fixed tooth heights under nonlinear temperature load,pressure load and thermal-mechanical load coupling are analyzed and compared,by comparing the analysis results with the relevant numerical analysis conclusions and experimental results in the existing literature,the correctness of the simulation model and the reliability of the data are verified.(4)Based on the deformation difference caused by the physical properties of different materials on the high pressure ratio and variable tooth height scroll plate,the stress and deformation laws of the orbiting scroll plates of cast aluminum,cast copper and cast iron under nonlinear temperature load,pressure load and coupling load are analyzed.