FRACTAL MODELLING OF THE STATIC FRICTION COEFFICIENT IN ELLIPTIC HERTZIAN WHEEL-RAIL CONTACT

Laura Mariana BABICI, Andrei TUDOR, Jordi ROMEU

Abstract


This research determined that the static friction coefficient uses a fractal approach, which combines the fundamental principles of fractal geometry with the mechanics of contact in both Hertzian wheel-rail systems and the interactions of flat-cylinder specimens that involve rough surfaces. Using the Weierstrass-Mandelbrot model, the study examines the transition through various deformation states, considering the static COF as indicative of the softer material's intrinsic properties and influenced by fractal parameters. Contrasting with the traditional assumption of a homogeneous contact surface, this study integrates fractal properties to calculate the actual contact area more precisely. This approach offers a more nuanced understanding of surface interactions, establishing static COF as a crucial factor for adhesion and a performance indicator in railway operations.

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