考虑材料温变特性的三维轮轨接触热分析

Three-Dimensional Wheel–Rail Contact Thermal Analysis Considering Temperature-Dependent Material Property

为研究材料温变特性对轮轨接触行为和摩擦温升的影响,提出了一种考虑材料温变特性的三维轮轨热力耦合模型,能够考虑纵、横向蠕滑率和自旋的影响,更为真实地模拟轮轨系统的服役状态.首先,研究了热力耦合建模方式对轮轨界面摩擦温升及接触应力的影响;随后,将该模型应用于地铁小半径曲线处车辆-轨道相互作用模拟.结果表明:当轮轨界面温度达到450℃时,轮轨接触应力显著降低,降幅可达20%;考虑热力耦合建模后,轮轨界面的预测温升明显低于不考虑热力耦合建模时的结果,在蠕滑率为0.16时,两者的差异可达51%;地铁车辆在小半径曲线线路上运行时轮轨摩擦温升因过大的蠕滑率与自旋会急剧增大到750℃,应考虑轮轨热力耦合建模以避免过高估计轮轨摩擦温升以及轮轨接触应力.

In order to study the influence of the temperature-dependent material property on the wheel–rail contact behavior and frictional temperature rise,a three-dimensional wheel–rail thermal-mechanical coupling model considering the temperature-dependent material property was proposed in this paper,which could consider the longitudinal and lateral creepage rates and spins to simulate the service state of the wheel–rail system more realistically.In this paper,the influence of the thermal-mechanical coupling modeling method on the wheel–rail frictional temperature rise and contact stress was first studied.Subsequently,this model was applied to the simulation of vehicle–rail interaction of subways running on a small radius curve.The results show that when the temperature reaches 450℃,the wheel–rail contact stress is significantly reduced by 20%.After considering the thermal-mechanical coupling modeling,the predicted temperature rise of wheel–rail interface is significantly lower than that without considering the thermal-mechanical coupling modeling.When the creepage rate is 0.16,the difference between the two can reach 51%.Due to excessive creepage rate and spin,the wheel–rail frictional temperature rise will increase sharply to 750℃when subways run on a small radius curve.Therefore,the wheel–rail thermal-mechanical coupling modeling should be considered to avoid overestimating the wheel–rail frictional temperature rise and wheel–rail contact stress.