Study on Wheel-Rail Rolling Contact-Impact Behavior at High-speed Rail Welds under Variable Friction Conditions
The wheel-rail rolling contact behavior can be described more accurately by using variable friction coefficient.In order to study the effect of variable friction coefficient on wheel-rail rolling contact behavior at rail weld,a three-di-mensional wheel-rail transient rolling contact finite element model was established for three different rail weld conditions.By comparing the results of Coulomb friction coefficients,the effects of variable friction coefficients on wheel-rail forces,micro slip within contact area and stick-slip distribution were calculated and analyzed.The results show that the propor-tion of the sliding area in the contact area with variable friction coefficient will be larger and the stick-slip oscillation will be caused in the sliding area.The more obvious the sliding phenomenon at the wheel-rail interface is,the more severe the stick-slip oscillation will be.The variable friction coefficient has minor effect on the normal contact solution,while the tangential contact solution is significantly affected by the change of contact state,resulting in uneven wear of convex 1 weld.The variable friction coefficient will affect the von Mises stress distribution,with the location of the maximum von Mises stress moving towards the bottom of the rail,affecting the location of the damage.
variable friction coefficientrail weldthree-dimensional transient rolling contactexplicit finite element methodwheel-rail contact solution