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- Krishna, Visakh V, et al.
(författare)
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Rail RCF damage quantification and comparison for different damage models
- 2021
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Ingår i: Railway Engineering Science. - : Springer. - 2662-4745 .- 2662-4753.
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Tidskriftsartikel (refereegranskat)abstract
- There are several fatigue-based approaches that estimate the evolution of Rolling Contact Fatigue (RCF) on rails over time, built to be used in tandem with Multi-Body Simulations of vehicle dynamics. However, most of the models are not directly comparable with each other since they are based on different physical models even though they shall predict the same RCF damage at the end. This article studies different approaches to quantifying RCF and puts forward a measure for the degree of agreement between them. The methodological framework studies various steps in the RCF quantification procedure within the context of one another, identifies the ‘primary quantification step’ in each approach and compares results of the fatigue analyses. In addition to this, two quantities - ‘similarity’ and ‘correlation’ have been put forward to give an indication of mutual agreement between models. Four widely used surface-based and subsurface-based fatigue quantification approaches with varying complexities have been studied. Different operational cases corresponding to a metro vehicle operation in Austria have been considered for this study. Results showed that the best possible quantity to compare is the normalized damage increment per loading cycle coming from different approaches. Amongst the methods studied, approaches that included the load distribution step on the contact patch showed higher similarity and correlation in their results. While the different approaches might qualitatively agree on whether contact cases are ‘damaging’ due to RCF, they might not quantitatively correlate with the trends observed for damage increment values.
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| 2. |
- Six, Klaus, et al.
(författare)
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Assessment of running gear performance in relation to rolling contact fatigue of wheels and rails based on stochastic simulations
- 2019
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Ingår i: Proceedings of the Institution of mechanical engineers. Part F, journal of rail and rapid transit. - : Sage Publications. - 0954-4097 .- 2041-3017. ; 234:4, s. 405-416
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Tidskriftsartikel (refereegranskat)abstract
- In this work, the authors present a methodology for assessing running gear with respect to rolling contact fatigue of wheels and rails. This assessment is based on the wheel/rail contact data of different wheel profile wear states obtained from a wheel profile prediction methodology. The approach allows a cumulative assessment of the rolling contact fatigue of rails in different curve radii (e.g. the sum of damage over the lifetime of wheel profiles). Furthermore, the assessment of the rolling contact fatigue can be undertaken at different wear states of the wheel profiles to provide an insight on how the rolling contact fatigue of wheels and rails varies depending on the evolution of wheel wear. The presented methodology is exemplarily applied to two bogie types, the UIC-Y25 standard bogie and the so-called FR8RAIL bogie with a mechanical wheelset steering device. The presented methodology has been shown to be a useful tool for the optimisation of vehicles already in an early stage of the vehicle development process.
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