发展一种利用商业有限元软件进行摩擦系统全模型摩擦噪声预测的方法,可以对包括摩擦力和真实边界条件下的摩擦系统的复特征值进行分析,提出进行摩擦噪声预测的主要步骤。该方法能够大大提高摩擦噪声预测分析的精度和效率。利用该方法分析往复滑动摩擦系统的噪声发生趋势,获得系统特征方程的特征根及其变化特性,据此可判断摩擦系统自然频率和可能发生摩擦噪声的频率。计算结果表明,摩擦因数和滑动方向对系统摩擦噪声的形成有重要影响,摩擦噪声发生时摩擦系统具有振动模态重合的特点。将计算得到的系统可能发生摩擦噪声的频率与系统的试验噪声频率进行比较,发现有比较好的一致性。
A method using a commercial finite element tool to predict the squealing onset of friction systems is developed. It can be applied to carry out a complex eigenvalue analysis of friction systems including the friction force and boundary conditions. Main procedures to apply the method are proposed. The developed method can improve clearly the accuracy and efficiency for evaluating friction squeal. As an application, it is used to predict the propensity of a reciprocating sliding system generating squeal. A full scale model of a reciprocating sliding system is established and meshed, which includes the friction force and actual boundary conditions. The eigenvalues and eigenvectors of the motion equations of this model are obtained using the method developed. Of these eigenvalues, all image parts of the eigenvalues with positive real parts correspond to the vibration frequencies associated with possible squeal. The modeling analysis results show that the coefficient of friction and direction of friction sliding have a distinct influence on the occurrence of squeal. The friction system is characterized by mode merging when squeal occurs. In comparison with the vibration frequency acquired from the squeal test, it is found that the frequency predicted by the present method is in a good agreement with the test result.