摘要
机械零部件中的结合面刚度影响整体结构的动态特性,刚度模型是否准确是影响整体结构动力学模型的关键因素之一。将结合面假设为刚性光滑平面与粗糙平面之间的接触,基于Weierstrass-Mandelbrot函数建立结合面三维实体模型,并进行有限元静力学分析,获得外加载荷与结合面变形之间的函数表达式,利用微分关系建立结合面法向与切向刚度与外加载荷呈现K=m Pn的指数关系。通过对已有研究成果对比,验证了所建刚度模型的正确性,并获得重要结论:结合面法向刚度和切向刚度有着相同的变化趋势,即随着法向载荷的增大,法向与切向刚度随之增大;系数m随着分形维数D的增加而递增,而系数n却随之减小。
The stiffness of joint interfaces has an influence on the dynamic characteristics for mechanical parts, and the validity of stiffness model is one of the key factors for the whole dynamic model.The joint interfaces are assumed by rigidsmooth plane and rough plane,and the Weierstrass-Mandelbrot fractal function is used to generate the fractal surface, then the static analysis is conducted by FME （finite element method）, achieving the relationship between pressure and deformation, an exponential relationship model （K=mPn）between normal/tangential stiffness and pressure is achieved by differential method. The validity of the model was verified with an example ,the results show that the variation tendency is the same of normal stiffness and tangential stiffness ,the contact stiffness increased with the pressure, coefficient m increased and exponent n decreased with fractal dimension D.
出处
《机械设计与制造》
北大核心
2016年第12期252-256,共5页
Machinery Design & Manufacture
基金
国家自然科学基金资助项目(51305327
51475352)
高等学校博士学科点专项科研基金资助项目(20136120120020)
陕西省自然科学基金项目资助(2014JQ7270)
关键词
结合面
分形理论
法向刚度
切向刚度
Joint Interface
Fractal Theory
Normal Stiffness
Tangential Stiffness
