驱动桥啸叫试验与降噪措施研究

Test and Improvement of The Drive Axle Whine

为了降低驱动桥的啸叫,进行整车试验和驱动桥总成的模态试验。试验结果显示,车内噪声主要是发动机的2阶和4阶噪声;大多数车速下,车内的后桥阶次噪声与总噪声的声压级相差10 dB(A)以上,主观感受不明显;但是在90 km/h时,当后桥齿轮的啮合激励引起后桥共振时,车内的后桥阶次噪声明显,后桥阶次噪声和总噪声的差值小于6 dB(A),能明显感觉到后桥啸叫。通过对桥壳结构的改进,将驱动桥共振的模态频率转移到常用工况以外,并通过有限元和边界元的方法仿真计算改进前后的桥壳辐射噪声。仿真结果显示,改进后的驱动桥在90 km/h时的噪声降低了大约4 dB(A)。

In order to reduce the drive axle whine, the vehicle test and the drive axle modal test were performed. The results demonstrated that the vehicle interior noise is mainly the two and four order noise of the engine. Under most speed, the order noise of the rear axle in the vehicle is not obvious, as it is lower than the total vehicle interior noise 10 dB(A). But at 90 km/h, the order noise of the rear axle in the vehicle is obvious, because the meshing excitation of the rear axle gear causes the resonance of the rear axle. And the difference between the order noise of the rear bridge and the total noise is less than 6 dB(A).Through the improvement of the axle housing structure, the modal frequency of the drive axle resonance was transferred to the uncommon working condition. The radiation noise of the axle housing before and after the structure improvement is simulated by the finite element and the boundary element method. The simulation results show that the noise reduction of the drive axle at 90 km/h is about 4 dB(A)after the structure improvement.