为准确计入结合面表面微观形貌对结合面的影响,提出结合面的"固-隙-固"接触模型。基于该接触模型和接触分形理论以及赫兹理论,建立考虑摩擦因素影响的结合面切向接触阻尼的分形预估模型,并通过数值仿真研究揭示有关参数对结合面切向接触阻尼的影响,为后续结合面动力学建模和动力学特性分析做准备。仿真分析结果表明:结合面的切向接触阻尼随结合面实际接触面积的增大而增大;随结合面法向载荷的增大而减小;随结合面间摩擦因数的增大而趋于恒定;实际接触面积影响cte*-μ曲线转折点(即临界摩擦因数μc)的位置,随着实际接触面积的增大,临界摩擦因数μc亦同时增大;不同的分形维数取值,尤其是分形维数取值在临界值(D=1.55)的两侧时,结合面间的接触行为存在较大差异。
In order to accurately consider the influence of micro-morphology on the joint surface,the "solid-gap-solid" contact model of joint surface is proposed.The fractal prediction model of the tangential contact damping of joint surface is established based on the "solid-gap-solid" contact model,contact fractal theory and the Hertz theory.And the influence of relevant parameters on the tangential contact damping is revealed with the research of numerical simulation.All the work provides the preparation for follow-up dynamic modeling and dynamic analysis of joint surface.Simulation results show that tangential contact damping of joint surface increases with the increase of real contact area,reduces with the increase of normal load of joint surface and tends to be constant with the increase of friction coefficient between the joint surfaces.Real contact area influences the location of the turning point of the cte*-μ(critical friction coefficient μc).With the increase of the real contact area,critical friction coefficient μc increases at the same time.Big differences exist between the contact behaviors with the different fractal dimension values,especially on both sides of the fractal dimension critical value(D=1.55).