Research On Optimization Of Vibration And Noise Of Automobile Transmission

With the progress of technology and the improvement of people's living standards,the car gradually enters into people's daily life.In the development situation of automotive industry,as an important part of vehicle's power train,the transmission is becoming one of the main noise sources of the car,with the increasing requirement of vehicle sound quality,the urgent needs for significant reduction of the interior noise is put forward.At the same time,the situation of environment protection is more and more severe,many strict policies are carried out to limit the cars' sound level in many countries,reducing the vibration noise of transmission is becoming the inevitable requirement of environmental protection.So optimizing the transmission's sound and vibration level is of great significance to automotive industry's development and environment protection.In this paper,a five speed manual transmission is researched,the optimizing control of its noise and vibration is realized by simulation and measurement,and a process to optimize the transmission's NVH performance is presented.The main content includes:Firstly,the mechanism of transmission's vibration and noise is analyzed,the principle and method of gear tooth micro-modification is studied,and the definition and measurement of the gear tooth correction parameters is introduced;Secondly,the dynamic model of the gearbox including axles,gears and bears is built using Romax Designer engineering software.The 3D house finite element model is built,and is imported into the Romax Designer model after finite element calculation.The transfer errors and contact points of the gear pairs is calculated and the modal of the house is analyzed based on finite element model.Thirdly,the comparison analysis between tested model of house and simulation result of the sample pieces is carried.The vibration and noise of sample pieces are measured in the semi-anechoic chamber and the whole vehicle respectively.The causes of the transmission noise are determined and the optimization scheme is developed through the analysis and evaluation.Finally,the samples is carried out according to the developed optimization scheme.The test results verify the effectiveness of the optimization scheme,which can realize the optimal control of the vibration noise of the transmission.