考虑摩擦的球面法向接触阻尼计算修正模型

A modified model for spherical normal contact damping calculation considering friction

基于M-B分形接触模型,通过引入球面岛屿密度分布函数,从而获得球形接触面接触载荷与真实接触面积之间的函数关系,并推导出单微凸体弹塑性应变能计算公式,结合阻尼损耗因子模型,最终建立考虑摩擦的球面法向接触阻尼计算模型。通过MATLAB对主要参数进行分析仿真可得到:球面法向接触阻尼随着法向载荷的增加逐渐增大;摩擦系数取值对球面法向接触阻尼的影响较为明显,当摩擦系数大于0.4时,法向接触阻尼斜率上升较为显著;随着分形维数的增大,法向接触阻尼变化较为复杂,当分形维数在1.6左右时,法向接触阻尼斜率最大;另外,粗糙度幅值参数的变大会导致法向接触阻尼增长更加迅速;相同载荷下,外接触比内接触能够获得更大的法向接触阻尼。

Based on the M -B fractal contact model,by introducing the spherical island density distribution function,the function rela- tionship between the contact load of the spherical contact surface and the real contact area was obtained,and the elastic-plastic strain energy calculation formula of single micro-convex body was deduced.Combined with the damping loss factor model,a spherical normal contact damping calculation model considering friction was finally established.Through the analysis and numerical simulation by MATLAB,it is found that the spherical normal contact damping increases gradually with the increase of normal load.The effect of friction coefficient on spherical surface normal contact damping is obvious,when the friction coefficient is greater than 0.4,the slope of normal contact damping is enhanced more significantly.With the progress of fractal dimension,the change of normal contact damping is more complicated.When the fractal dimension is around 1.6,the slope of the normal contact damping is the largest.In addition,the augment of roughness amplitude parameter will cause the normal contact damping to rise more rapidly.Under the same load,the external contact can attain a larger normal contact damping value than the internal contact.