A numerical model for the analysis of heavy freight trains dynamics with respect to running safety

The dynamics of heavy freight trains might pose safety issues when strong driving or braking actions (i.e. emergency braking) are required while the train is running on turnouts or sharp curves. Besides being expensive, an experimental investigation of safety condition does not usually provide a deep understanding of the problem: the information collected with experimental tests are relevant to a particular trainset running on the specific track considered. On the other hand, numerical simulations can represent a useful tool to analyse a wider range of operating conditions, allowing to investigate the effect of several factors (i.e. trainset composition, track geometry etc) on running safety. For this reason, a numerical procedure has been developed to reproduce the dynamics of a whole trainset: a numerical model designed for the analysis of the trainset longitudinal dynamics (TSDyn TrainSet Dynamics simulator) was joined with a multibody model for the simulation of vehicle’s running behaviour (MoNSTram MOdular Non Stationary TRAMcar dynamics simulator) originally developed to analyse the dynamics of modular tramcars. The proposed numerical procedure allows to investigate the influence of track geometry, trainset composition, and buffers’ response on the dynamic behavior and to perform analyses according to the leaflets (EN14363 and UIC 518) with respect to running safety.