Simulation Study On Vibration Response Of Gear System

Gear transmission is widely used in many kinds of machinery equipment.Along with the demand of higher speed and high-power in machinery industry,gear transmission is also developing towards high-speed and heavy-load.The demand of vibration and noise control becomes more and more stringent while the environment protection consciousness of the people improves.In this thesis,a gearbox bench with spur gears is chosen as analytical model,the problems which include mesh excitation modeling,the gearbox especially the connection element modeling,the effect of the lubricant on the gearbox modes are deeply studied,and the vibration response in time domain of the gearbox is predicted using finite element method.The major work in this thesis is listed as follows:1.Stiffness excitation model of the gear system is given and the models of error excitation and impact excitation are built using error approximation equivalent method and meshing impact equation,then interior synthesis excitation model is also obtained.2.3-D dynamic model of the gearbox is built,the methods of rigidly coupling 16-node to build the bolt connecting element and simulating the dynamic character effect of lubricant on the gear box using fluid-structure coupling are proposed.The results of the simulation and experiment agree well with each other,it proves effective for the two methods.3.Vibration response of the gearbox is calculated with the excitation model and transient solution function of Ansys using finite element method,the excitation model is also calculated using the rigid-flexible coupling solution function of the LMS Virtual.Lab,the response is validated with sub-structure method.The results of the experiment and the simulation are in good agreement.