Finite Element Analysis of Tire Traction Using a Rubber-Ice Friction Model

The friction of road surface covered by snow or ice is very low and that results in reducing vehicle traction forces and potential traffic accidents. In general, to establish a master curve on a rubber-ice friction model is difficult because the ice surface, being not far removed from its melting point, reacts itself very sen-sitively to pressure, speed, and temperature changes. In this paper, an accepta-ble frictional interaction model was implemented to finite element method to rationally examine the frictional interaction behavior on ice between the tire and the road surface. The formula of friction characteristic according to tem-perature and sliding velocity on the ice surface was applied for tire traction analysis. Numerical results were verified by comparing the outdoor test data and it was confirmed to indicate similar correlation. It is found that the rub-ber-ice friction model will be useful for the improvement of the ice traction performance of tire.

函数型摩擦系数条件下轮轨滚动和滑动接触的热机耦合分析

以直径为860mm的LMA型踏面轮对和60kg.m-1钢轨为例,在考虑轮轨间热传导以及轮轨与环境间的热传导和热辐射基础上,采用非线性有限元分析软件ABAQUS提供的mixed Lagrangian-Eulerian方法建立轮轨接触的热机耦合有限元模型,并采用隐式和显式相结合的方法分析轮轨滚、滑动接触工况下的热机耦合问题。结果表明:轮轨滚动接触时,轮轨间的摩擦温升较小、不影响轮轨表面的材料性能,工程上可以忽略其温度对轮轨接触特性的影响;轮轨滑动接触时,轮轨间的摩擦温升足以改变轮轨表面的材料性能,进而影响摩擦系数,且不同摩擦系数对轮轨接触热机耦合特性影响也较大,因此采用与相对滑动速度、温度和载荷等因素相关的函数型摩擦系数可以准确分析轮轨滑动接触的热机耦合特性。

滑动摩擦热效应浅析

本文分析了在摩擦过程中热的产生和扩散，阐述了热效应对摩擦性能的影响及在机械设计中考虑摩擦学设计的重要性。