基于ANSYS的轮轨摩擦生热分析

发布时间：2018-05-27 01:43

本文选题：轮轨摩擦 + 温升　；参考：《西南交通大学》2011年硕士论文

【摘要】：随着铁路的高速化、重载化,车轮踏面和钢轨表面的擦伤和剥离破坏越来越严重。车轮运行中的摩擦生热是引发磨损破坏的主要因素,所以分析轮轨接触的温度场和应力场具有重要意义。主要应用大型有限元软件ANSYS分别建立车轮在钢轨上滑动和滚动过程的有限元模型,在轮轨接触区利用接触单元法来建立接触。模型中考虑了车轮和钢轨接触间的热传导,以及自由表面与环境的热对流,假设摩擦功全部转化为摩擦热,摩擦热流平均分配给车轮和钢轨。通过直接耦合法求解轮轨间的摩擦生热,详细的分析了接触区内的瞬时温度场、应力场、剪应力和接触区的接触压力分布特征,以及最高温升和应力的变化趋势。在纯滑动工况中,轮轨接触表面很容易产生瞬时的高温：1)材料的非线性影响不可忽略；2)轮轨的热效应影响层很薄,最高温升和应力产生在表面中线靠后处；3)轮轨表面最高应力和温度均随着轴重、速度及摩擦因数的增大而增大。在滚滑工况中,由于温升较小,计算中未考虑材料的非线性影响。结果表明：1)高速列车车轮在低蠕滑率下运行时,温升不高,但也产生了可观的热应力,由于接触时间很短,使得最高温升产生于远离接触区的部位；2)车轮滚动过程中承受冷热交替的载荷,很容易产生破坏；3)最大剪应力产生于接触表面很薄层,在此薄层容易产生剪切破坏；4)随着轴重、摩擦因数和蠕滑率的增大轮轨的摩擦热效应越明显。本文计算分析将为探讨轮轨擦伤和剥离提供理论参考,对于揭示热损伤机理有很大的指导意义。
[Abstract]:This paper analyzes the thermal conduction between wheel and rail and the thermal convection between the free surface and the environment , and analyzes the transient temperature field , stress field , shear stress and contact pressure distribution characteristics of the contact zone , and the change trend of the highest temperature rise and stress .

In the pure sliding mode , it is easy to produce instantaneous high temperature : 1 ) the nonlinear influence of the material is not negligible ;
2 ) the thermal effect of the wheel track is very thin , and the highest temperature rise and the stress are generated at the rear part of the surface center line ;
3 ) The highest stress and temperature on the surface of the wheel track increase with the increase of axle load , speed and friction factor .

The results show that : 1 ) When the high - speed train wheel runs at low creep rate , the temperature rise is not high , but also considerable thermal stress is generated , and the contact time is short , so that the highest temperature rise is generated at the part far from the contact area ;
2 ) the alternating load of cold and heat during the rolling process of the wheel can be easily damaged ;
3 ) the maximum shearing stress is generated in a thin layer of the contact surface , and shearing damage can be easily generated in the thin layer ;
4 ) As the axle load , the friction factor and the creep rate increase the friction heat effect of the wheel rail is more obvious .

The calculation and analysis of this paper will provide a theoretical reference for the discussion of wheel - rail friction and peel - off , which is of great significance to reveal the mechanism of thermal damage .
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TH117.1

【参考文献】