Study of disc brake's NVH characteristics in test environment
In this article,both the multi-body dynamic method and the acoustic boundary element method are used to explore the disc brake's NVH characteristics.Firstly,the brake's rigid-flexible coupling model in the test environment is set up,and the influencing factors of the braking NVH characteristics are analyzed from three aspects:structure,excitation source and trans-fer path.Then,the acoustic boundary element method(BEM)is used to simulate the noise emitted by braking vibration,which is directly compared with the test results.It is shown that the natural frequencies of the-second-to-the-fifth order axial modes of the braking disc,the-second-and-the-third order axial modes of the bracket,as well as the first-order axial modes of the braking clamp and the connecting plate are close to the noise frequency of the bench test,which may cause resonance and produce braking noise.The braking NVH characteristics can be improved by changing the damping coefficients of the braking disc and the friction lining without affecting the braking performance.The vibration at the lower end of the suspension spiral spring is the largest,and the shock absorber and the bushing have significant damping effect on the vibration.According to the simulated sound pressure level cloud map,the sound pressure level of the contact part between the braking disc and the friction disc is the largest;it in-creases first and then decreases with the increase of frequency.The comparative analysis indicates that the trend is consistent with the results of the measuring points'noise in the bench test.
万方数据
维普
