Comparison between quasi-static and multibody dynamic simulations for wheel-rail contact analysis

Rails experience contact with a range of wheel profiles that pummel their surface at different points and with different intensities. This work compares two methods for evaluating pummeling analyzes for the wheel-rail interaction: simplified quasi-static model and multibody dynamics simulations. The first is solved with the GIRAFFE program and simulates the interaction of a single wheelset with the rail in a quasi-static approach. In the second, the full dynamics of a railway wagon on a track layout are evaluated using the multibody dynamics simulation programs SIMPACK (R) and VAMPIRE (R). The proposal for a quasi-static model is to reduce the time and computational effort to perform a pummeling analysis and quickly evaluate thousands of cases of wheel-rail contact. Track parameters and vehicle loads of a heavy haul railway are considered for the simulations. The results showed that the quasi-static model has a good correlation with the dynamic models on tangent track sections. For the curved sections, differences were observed in the distribution of pressures due to the absence of creep forces in the quasi-static model. The comparison between the models also showed slightly different results due to the different calculation of contact in each approach. The quasi-static approach reduced the time consuming by at least 73.4% over the multibody approach. Notwithstanding, the proposed model shows to be promising in replacing complete dynamic analysis for time-consuming tasks such as pummeling.