多参数摩擦模型及其在机构动力学分析中的应用  

Multi-parameter Friction Model and Its Application to Dynamics Analysis of a Mechanism

作　　者：原大宁 康锋 

机构地区：[1]甄安理工大学,西安710048

出　　处：《机械科学与技术》2009年第7期936-940,共5页Mechanical Science and Technology for Aerospace Engineering

基　　金：国家自然科学基金项目(50575180);陕西省教育厅科研项目(06JC07)资助

摘　　要：论述了多参数摩擦模型中各参数的物理意义及其取值。分析了指数+双曲正切摩擦模型中,Stribeck速度vs和双曲正切函数中参数k的关系,得出了要使摩擦力曲线峰值fmax与静摩擦力fs的比值的误差小于5%,应使k≥(10/vs)的结论。基于指数+双曲正切摩擦模型,建立了游梁式抽油机非线性动力学分析模型,应用数值迭代法求解,获得了驱动力矩和机械效率的变化规律。理论计算与实际现象相符合,说明在机构动力学仿真中,指数+双曲正切这一多参数摩擦模型较之库仑摩擦模型能更精确地反映运动副耗散力的影响。The physical meaning and selection of parameters of multi-parameter friction models are discussed. The relationship between Stribeck velocity v, and coefficient k in the exponent ＋ hyperbolic tangent friction model is ana- lyzed. It is found that in order to guarantee that the error of ratio between the peak value fmax Of friction curve and the static friction f, is less than 5%, there should be k ≥ （ 10/v, ）. In addition, based on the exponent ＋ hyperbolic tangent friction model, the nonlinear dynamic equation of a linkage mechanism for beam pumping unit is estab- lished. The nonhnear dynamic equation is then solved by using the numerical iterative method ; the curve of driving torque acting on the crank and the mechanical efficiency of this system are obtained. The theoretic analysis result agrees with the actual phenomenon. It is shown that the exponent ＋ hyperbolic tangent friction model is more precise than the Coulomb friction model for describing the energy dissipation in mechanism dynamic simulation.

关 键 词：摩擦模型 机构动力学 机械效率 

分 类 号：TH112[机械工程—机械设计及理论]