Improved Wheel-Rail Adhesion Estimation

Activity: Talk or presentation typesOral presentation

Description

This paper presents a simple method to improve the adhesion estimation during train braking in low adhesion conditions. The proposed method uses fundamental laws of mechanics by finding the relationship between the wheel acceleration and the acting force/torque and linking this to the available adhesion. The proposed method was developed to more accurately estimate the adhesion at each wheelset using data collected during the sander trial project that funded by the Rail Safety and Standards Board (RSSB). This will give a better understanding of the available adhesion and how it changes due to the cleaning (conditioning) after each wheel passage and sanding effects. A mathematical model, which links the adhesion to the measured Brake Cylinder Pressure (BCP) and the wheelset speed, has been used to estimate the adhesion for different scenarios reported in sander trial project. The simulation results show that the proposed method successfully estimated the adhesion value. It was found that the available adhesion was greater than that achieved. The peak of adhesion occurs at about 5% creepage, but as the Wheel Slide Protection (WSP) acts to push the creepage to about 20% hence the achieved adhesion was at a lower value. As the main inputs for the proposed method are the wheel speed and the BCP, which are both measurable, this method could be used as starting point for real-time adhesion estimation, which have several important applications such as adaptive WSP that tracks the optimal adhesion level, in cab display showing the railhead condition to drivers or providing information to a centralised control room that can distribute this information to the other services on the same line.
Period7 Jun 2022
Event title13th World Congress on Railway Research: Reshaping our railways post-pandemic: Research with an impact
Event typeConference
LocationBirmingham, United Kingdom
Degree of RecognitionInternational