The project is motivated by the issue of low adhesion in wheel-rail contacts, which can cause serious problems with traction and braking in railways. This issue is frequently connected to the ‘wet-rail’ phenomenon where the contact is naturally contaminated with a mixture of water and solid particles. At a critical particle concentration, a significant drop in the friction coefficient can be observed. Although the phenomenon is well known from railway operations, the physical relationships are not yet fully understood. The aim is to provide experimental evidence of the transient nature of the phenomenon in rolling contacts contaminated with a water-particle suspension based on optical observation of the contact and to provide a physics-based model describing this phenomenon in its full complexity. Ball-on-disc optical tribometer combined with thin-film colorimetric interferometry and fluorescence imaging will be used for fluid film thickness and flow measurement. Particle-based simulations (DEM) will be coupled with flow simulations between rough wheel-rail surfaces.

Keywords
contact;friction;wheel/rail interface;solid particles; suspension

24-14624L

English

Křupka Ivan, prof. Ing., Ph.D. - principal person responsible

Institute of Machine and Industrial Design
- responsible department (14.12.2023 - not assigned)
Institute of Machine and Industrial Design
- beneficiary (14.12.2023 - not assigned)

JORDÁN, T.; GALAS, R.; OMASTA, M.; KŘUPKA, I.; HARTL, M. COMPREHENSIVE ASSESSMENT OF SOLID STICK FRICTION MODIFIERS IN WHEEL/RAIL CONTACT. Tokyo, Japan: Japanese Society of Contact Mechanics on Railway, 2025. 7 p.
Detail

OMASTA, M.; SIX, K.; KVARDA, D.; GALAS, R.; SUHR, B.; KŘUPKA, I.; TRUMMER, G.; HARTL, M. On the transient mechanism of water-particle induced low-adhesion phenomenon. Proceedings of the 13th International Conference on Contact Mechanics and Wear of Rail/Wheel Systems (CM2025). Tokyo: Japanese Society of Contact Mechanics on Railway (JSCMR), 2025. 6 p.
Detail

Responsibility: Křupka Ivan, prof. Ing., Ph.D.