Physical processes in wheel–rail contact and its implications on vehicle–track interaction

Abstract

Friction within the wheel–rail contact highly influences all aspects of vehicle–track interaction. Models describing this frictional behaviour are of high relevance, for example, for reliable predictions on drive train dynamics. It has been shown by experiments, that the friction at a certain position on rail is not describable by only one number for the coefficient of friction. Beside the contact conditions (existence of liquids, solid third bodies, etc.) the vehicle speed, normal loading and contact geometry are further influencing factors. State-of-the-art models are not able to account for this sufficiently. Thus, an Extended-Creep-Force-Model was developed taking into account effects from third body layers. This model is able to describe all considered effects. In this way, a significant improvement of the prediction quality with respect to all aspects of vehicle–track interaction is expected.

Keywords:

• wheel–rail contact
• traction
• friction modelling
• tribological effects
• third body layer

Acknowledgements

The authors acknowledge the financial support of the ‘COMET - Competence Centers for Excellent Technologies Programme’ of the Austrian Federal Ministry for Transport, Innovation and Technology (bmvit), the Austrian Federal Ministry of Science, Research and Economy (bmwfw), the Austrian Research Promotion Agency (FFG), the Province of Styria and the Styrian Business Promotion Agency (SFG).

We would furthermore like to express our thanks to our supporting industrial and scientific project partners, namely L.B. Foster Rail Technologies, Corp., ÖBB Infrastruktur AG, Siemens AG Österreich, voestalpine Schienen GmbH and to the Graz University of Technology.