Influence of wheel/rail contact modelling on vehicle stability assessment using numerical simulations

One of the most important aspects to guarantee the ride comfort and running safety of a rail vehicle is to ensure its stability in its entire service life. A key factor in achieving this goal is the modeling of wheel/rail contact when numerical methods are used. While this topic has been explored previously, a comprehensive solution remains elusive due to the significant variations among existing models. To address this challenge, we conducted a comparative study using newly developed non-Hertzian models, namely FASTSIM-SDEC and SHE-SDEC, along with the widely used Simpack models. The numerical experiments of the selected case study reveal significant variations in the predicted critical speed of the same vehicle when different contact models are employed, which underscores the importance of using the proper contact model in this study. The findings enhance our understanding of the differences between available contact models and offer valuable guidance for choosing the most suitable model for rail vehicle stability analysis.