Study On NVH Analysis Of A Certain Type Of Vehicle Rotary Drive Axle

In recent years,the automobile industry develop rapidly,which makes the car entered the ordinary families, becoming one of the main means of transport, people's requirements on the ride comfort are also getting higher and higher when more attention are paying to the automobile power, smoke oil economy, safety and performance, automobile comfort is mainly related to vehicle interior riding environment, car vibration and noise Drive axle which is at the end of the automobile transmission system is an important part of automobile transmission system,it will have a great influence on the vibration noise of vehicle. This paper targets to drive the vibration and noise of bridge simulation analysis by finite element method and boundary element method.Drive axle assembly mainly includes the reduction gear vice, differential, wheel side reducer.Among the driving bridge vibration and noise of the influencing factors, the most important one is the reduction gear pair meshing impact, through accessing to relevant literature data. The impact will be transmitted to the axle through the gear bearing, which will cause the driving bridge shell vibration, then radiating noise. This paper mainly studies the car of the vibration and noise in a straight line running speed.In the straight line driving, differential does not work, and has slight influence on the assembly of the vibration and noise,it belongs to the omit factors. The differential can be simplified as a mass to simplify the model, the final model is composed of a main deceleration gear pair, a bearing, a main deceleration machine hull and axle components.The three-dimensional model of drive axle assembly is established in CATIA and imported into HyperMesh, after pre-processing mesh, quality inspection, the definition of material properties,the vibration mode and natural frequency are calculated within 2000Hz. The dynamic characteristics are simulated in the finite element analysis software ABAQUS through applying boundary conditions,the time domain data which is used for the analysis of the vibration of bridge shell excitation data is extracted from the surface of the bearing outer ring node,it is conversed into the frequency domain data by using FFT transform,then find the frequency of vibration and noise of large value; The axle housing of radiated noise is analysised by using bridge shell vibration analysis of the output displacement data as a boundary condition, viewing bridge shell surface radiated noise.According to the result of the simulation and analysis of the vibration and noise, the reasonable measures of vibration reduction and noise reduction are put forward. Simulation of vibration and noise of the improved model, it is found that this method can effectively control the radiation noise on the surface of the bridge.