Modal Characteristics Analysis And Optimization Research Of Critical Components Of Transmission Flow-Distribution Test Bench

At present,with the rapid development of automotive technology,the test benches for testing the performance of automobiles are developing in the direction of high precision and high quality direction,and transmission flow-distribution test bench is one of them.Improving the performance of various aspects of mechanical products is more and more important.The transmission flow-distribution test bench contains rotary machinery which will vibrate during normal operation.Severe vibration may cause deformation and reduce service life,and even cause destructive accidents.Therefore,how to solve the resonance problem and improve the system performance is the focus of research.Modal analysis technology can obtain the response of the structure under the action of various vibration sources and calculate modal parameter,so as to lay a foundation for keeping away from the natural frequency and improving the mechanical structure.Due to the rapid development of computer technology,the cost of modal analysis technology has been greatly reduced.In the field of dynamic analysis,modal analysis technology has become an indispensable tool.This paper is based on the critical components of transmission flow-distribution test bench.The motor base of the test bench is studied through the combination of the finite element simulation model and the test modal analysis.The modal characteristic of shaft structure is researched,and shaft structure is optimized to avoid resonance problems with test bench.According to the basic principles of finite element analysis method,the simulation model of motor base is established.The modal analysis of the motor base is performed by ANSYS.The motor base is improved by analysis results.The natural frequency of the motor base is researched under different boundary conditions in order to determine the appropriate installation method.The natural frequency of the motor base under different rib thickness is researched for improving the motor base and preventing resonance.ANSYS was used to analyze the modal characteristic of the shaft structure which are based on the theory of rotor mechanics and other rotary machinery.The modal parameters is studied by using ANSYS to establish the simulation model of the shaft structure.The degree of influence on the critical rotation speed when the parts on the shaft are not in the same axis position is analyzed in order to avoid resonance problem.Optimization of shaft structure is based on particle swarm optimization.The optimization goal,design variables and constraints are determined.The lumped mass model is used to calculate the critical speed and vibration displacement of the shaft structure so as to determine the fitness function,and update the particle position and velocity continuously,and obtain the optimal solution of the shaft structure bearing stiffness under certain conditions.The conditions required for the modal test platform during the test modal analysis are analyzed to determine the selection of test equipment such as hammers and sensors.Modal parameter identification methods are determined.Formulate test plan for motor base such as determining the support structure and excitation method of test structure.Test modal parameters such as natural frequency and vibration pattern of motor base are calculate.By studying the modal characteristic of critical components of the test bench.the structure and installation method of the motor base are determined,and the optimization model of shaft structure is obtained.Experimental modal analysis results are compared with simulation results in order to verify the accuracy of simulation model.The test method provides some basis for the experimental modal analysis of other structures.The resonance problem of the test bench is avoided.