Dynamic Simulation And Noise Radiation Analysis Of Planetary Gearbox Based On Rigid-Flex Coupling Modeling

The gear transmission system has a compact structure and accurate transmission,and is widely used in various types of mechanical equipment.Since the planetary gearbox will be affected by both internal and external excitations during its operation,its vibration and noise problems are more prominent.And the gearbox is under vibration environment for a long time,the reliability and service life of the equipment will be reduced.In addition,when the cabinet vibrates,it will stimulate air vibration to continuously radiate noise to the outside world,and long-term exposure to noise will threaten people's physical and mental health.In order to reduce the vibration and noise radiation of the gearbox during work,it is necessary to further improve the working performance of the gearbox,and conduct in-depth research on the dynamic response of the planetary gearbox and the radiated noise.Therefore,the study of planetary gearbox dynamics and its noise prediction provide a theoretical basis for the prediction of the overall vibration noise of the gearbox and the design of vibration and noise reduction.This article takes the planetary gearbox as the object,uses the rigid-flexible coupling method,and establishes a multi-rigid body model of the planetary transmission system according to the actual connection relationship of the components of the planetary gearbox,the time-varying meshing stiffness,damping characteristics and dynamic meshing force.Due to the complex vibration characteristics of planetary gearboxes,with linear and nonlinear dynamic behavior,and rigid bodies can only obtain the vibration response at the position of the center of mass,and cannot obtain the overall vibration response,the gearbox with large deformation and The inner ring gears are respectively flexibly flexible,and on the basis of obtaining the Craig-Bampton mode of the gear box body,it is coupled to the multi-rigid body system through the Interface point,thereby establishing the rigid-flexible coupling model of the planetary gear box.The time-varying meshing stiffness of the gear pair was obtained through simulation calculation,and compared with the time-varying meshing stiffness of the gear pair calculated by the improved energy method.The dynamic meshing force of the gear pair,the vibration response cloud diagram of the gear box surface and the vibration acceleration,velocity and displacement of the key points are calculated.The dynamic response of the gearbox under speed-up conditions was studied,and the bench test comparison and verification was carried out.An acoustic boundary element model was established,and the acoustic boundary element model of the planetary gearbox was solved using the MATV method.The sound pressure cloud map of the field point under the ATV value,steady state conditions and speed-up conditions was obtained.The results show that the meshing frequency of the gear transmission system increases gradually with the increase of the speed.The resonance band is mainly concentrated near the first-order natural frequency.These are caused by the natural frequency of the gear box,so the meshing frequency of the gear transmission system is The natural frequency of the gear box has a great influence on the noise radiation of the entire gear box.In this paper,the rigid-flexible coupling method is used to study the dynamics of the planetary gearbox,and the dynamic response of the gearbox under steady-state conditions and speed-up conditions is studied.On the basis of obtaining the CB mode of the gearbox,the MATV method is used to The noise prediction of the gearbox as a whole was carried out,and a bench test was carried out.The experimental results and the simulation results are in good agreement.The research results provide a theoretical basis for the prediction of the overall vibration noise of the gearbox and the design of vibration and noise reduction.