Study On Automobile Real Axle Vibration & Noise

The rear axle is the one of mainly vibration and noise resource in transmitting mechanism. Beside the noise from the gears and axletrees, and it makes the noise from rear axle housing vibration. Otherwise, because of the rear axle is sustained by suspension, and they lead to the rear axle flexural vibrations and torsional vibrations. Especially, when resonance vibration, the noise's SPL is very high. It will not only fall transmitting mechanism reliability but make the uncomfortable noise. At the same time, It's possible that result the vehicle body in vertical vibration and portrait vibration, consequently fall the amenity. In the past, the control method of the rear axle was based on experimentation, and lodged improved idea. The method's shortage is that experimenter's level influence the testing precision, and the testing equipment is extortionate. In this paper, Make use of CAD/CAE technology, and analyze the noise of a mini-vehicle's rear axle, and lodge the structure improved idea. In the paper, Firstly, introduce the process of make the model.ie under the UGII platform, simplify the original rear axle model and build finite element model used in modal, noise and transient analyzing, it base on pledging its the size and assembled relationship. During the process of building the model ,building the gears model accurately for reflecting the joggling noise of the gears rightly . Base on it , firstly analyse the rear axle housing about constraint modal within 2000Hz and vibration performance; And then analyse the rear axle about transient response, Lastly, extract the vibrational time-domain data of these nodes on the exterior surface of axletrees. Then take advantage of MATLAB to translate the time-domain data to frequency-domain data. By contrast to natural frenquency, find out the frequency where maybe produce higher vibration and noise and the amplitude. According to these frequency, analyse the rear axle in harmonic and noise analysis, and find out the main resource of noise and vibration. And the sim-analysis of vibration and noise at other speed, Evaluate the vibration and noise characteristic roundly, and draw some rule. Finally modify the rear axle structure of resource of noise on the condition that the new structure has no interference and great modification with the old structure. The measure is depressing the vibration by groove shank, consequently gain our ends of depressing the noise, and got a good effect.