Research On Low-noise For Gear Transmission With Digital Technology

One of the most effective ways to reduce automobile noise is the control of radiated noise of the transmission box. More emphasis was placed on vibration and noise control. This dissertation example for a certain type of transmission box and make research on the control of radiated noise of the transmission. This paper presents a effective program to solve such problems. This program can be used either in the improvement of existing transmission and the development process to predict the noise.Transmission housing noise is the most important components of the noise, which accounted for more than 90%. Therefore, this paper mainly studies the transmission house. The integrated use of multi-body dynamics, finite element, and boundary element method are to solve the problem. At last, the paper proposed a corresponding improvement program.First, establish the overall three-dimension solid model, then mesh the modal and carry on modal analysis, which get the natural frequency and mode shape. Meanwhile, the experiment assures the mesh is accurate. And then establish multi-body dynamics model of the transmission, to impose conditions consistent with the constraints, drive, load and other conditions. Compared to the results of the theoretical analysis, the simulation results proved to be true and credible. The results of the multi-body dynamic simulation of the gear shaft will be the driving forces on the housing as incentive loads. After set the real boundary conditions, the displacement, velocity and acceleration of the points on the housing will be calculated. After that, using the specialized software SYSNOISE to calculates the sound pressure. Finally, improve the design of the transmission housing base on the finite element calculation results and the sound pressure.This paper proposed a complete guidance of the design approach in the method of virtual prototyping. The process of design-prototype-improvement has been changed into design-virtual prototyping-design. Most of the work carried out on the computer, which shortened the design cycle and deduced the design cost.The noise control measure to reduce radiated noise of the transmission housing turn out to be working. All of these measures are very universal and economic. The research methods in this paper have some reference value to research radiated noise field of vibrated object.