【摘要】 基于分形理论,考虑摩擦因素的影响,应用描述三维粗糙表面形貌的W-M函数,推导了结合面切向阻尼能耗和切向等效黏性阻尼三维分形模型。使用Matlab软件进行仿真分析,结果显示:结合面的切向阻尼能耗随着法向总载荷、摩擦因数的增大而减小,随着材料塑性指数、切法向载荷比、分形粗糙度参数的增大而增大;结合面的切向接触阻尼能耗和分形维数之间的关系比较复杂;结合面的切向接触等效黏性阻尼随着摩擦因数、分形粗糙度参数的增大而减小,随着法向总载荷、切法向载荷比、材料塑性指数的增大而增大;结合面的切向接触等效黏性阻尼随着分形维数增大先增大后减小,在分形维数等于2.7附近时取最大值;当分形维数等于2.1～2.5时,结合面的切向接触等效黏性阻尼和法向总载荷呈现明显的非线性关系;当分形维数2.5～2.9时,结合面的切向接触等效黏性阻尼和法向总载荷趋于线性关系。更多还原

【Abstract】 Based on fractal theory,continuous smooth exponential model of elastic-plastic contact,and considering the influence of friction factors and applying an improved W-M function that simulating three-dimensional fractal profile surface,the fractal model of energy dissipation for tangential contact in joint interfaces and its equivalent viscous damping model are proposed.It is shown from the models that the tangential contact damping dissipating energy of joint interfaces decreases with the increase of normal load on joint interfaces,the friction coefficient,but increases with the increase of plastic index of contact materials,the ratio of the tangential dynamic load amplitude to normal contact load,the fractal dimension,the fractal roughness of joint interfaces. The variation rule of the tangential contact damping dissipating energy of joint interfaces with the fractal dimension is very complex. The tangential equivalent viscous damping of joint interfaces decreases with the increase of friction coefficient,the fractal roughness of joint interfaces,but increases with the increase of normal load on joint interfaces,the ratio of the tangential dynamic load amplitude to normal contact load,the plastic index of contact materials. The tangential contact equivalent viscous damping of the joint surface increases at first and then decreases with the increase of the fractal dimension,and the maximum value is taken when the fractal dimension is equal to 2. 7. There is an obvious nonlinear relationship between the tangential contact equivalent viscous damping of joint interfaces,when fractal dimension D value is between 2. 1 and 2. 5. There is an obvious linear relationship between the tangential contact equivalent viscous damping of joint interfaces and the normal contact load,when fractal dimension D value is between 2. 5 and 2. 9.更多还原