Mechanism of Rail Gouging Phenomena Induced by Microparticles During High-Speed Sliding Electrical Contact Based on SPH Method

The microparticles on the rail surface are recognized as one of the primary causes of the gouging phenomena during the high-speed sliding electrical contact processes. In this article, the mechanism of the rail gouging phenomena induced by the microparticles on the rail surface is studied by a modified smoothed-particle hydrodynamics (SPH) method, considering the velocity skin effect (VSE). First, based on the modified SPH method, a slider–rail model is established to explore the gouging processes under the collisions of microparticles on the rail surface. Then, the influence of the size and quantity of microparticles on the gouging damages is investigated. Finally, the formation mechanism of gouging damages induced by the microparticles is analyzed. The results demonstrate that as the horizontal velocity of the slider increases, the gouge craters on the rail surface become more extensive and pronounced. Furthermore, as the radius of the microparticle increases, the length of the gouge craters and the height of the gouge lips increase while the depth of the gouge craters increases first and then decreases. When the quantity of microparticles on the rail surface increases, both the length and the depth of the gouge craters and the height of the gouge lips rise. It is also found that the combined effects of localized pressure and heat concentration during the high-speed sliding electrical contact processes are the fundamental cause of the gouging damages to the rail surface. The results of this article may provide valuable insights for a comprehensive understanding of gouging damages in sliding electrical contact systems.