考虑域扩展因子的结合面接触刚度分形模型及数值仿真

FRACTAL MODEL AND NUMERICAL SIMULATION OF CONTACT STIFFNESS OF JOINT SURFACE CONSIDERING DOMAIN EXPANSION FACTOR

为了从分形的角度更加准确地研究结合面的接触刚度,基于M-B分形模型和赫兹理论,引入域扩展因子来表征分形维数,分别建立结合面法向和切向接触刚度分形模型。该模型综合考虑了载荷、分形维数以及材料参数等因素的影响。同时,通过数值仿真得到结合面接触刚度与各参数的变化趋势,结合面法向接触刚度与法向载荷的变化趋势相同,与分形特征和长度尺度系数相反,但与分形维数的变化趋势比较复杂,不再具有单调性;结合面切向接触刚度与上述参数引起的变化趋势与法向接触刚度的变化趋势相似。

In order to study the contact stiffness of the bonding surface in more detail from the perspective of fractal theory,on the basis of the M-B fractal model and the Hertz theory,a domain expansion factor is introduced to represent the fractal dimension to establish the normal and tangential contact stiffness fractal models of the bonding surface,respectively.The model comprehensively considers the effects of load,fractal dimension and material parameters on the contact stiffness.At the same time,the change trend of the contact stiffness of the joint surface and each parameter is obtained through numerical simulation.The change trend of normal contact stiffness and normal load is the same,which is opposite to the fractal characteristics and length scale coefficient,but the change trend of the fractal dimension is more complicated,no longer monotonic.The change trend caused by tangential contact stiffness and the above parameters is similar to that caused by normal contact stiffness.