Fast simulation of railway pneumatic brake systems

The pneumatic brake system is the most important safety component in freight trains. Understanding its behavior during operation is crucial to identify the causes of technical problems and to improve driving techniques. Commercial codes can be used to analyze the system, aiming to develop better braking procedures and to predict eventual problems. However, these codes are not aimed to improve driver's skills or to predict the effects of unexpected driver's actions on the system, which can be done using train simulators and requires real-time simulations. This work focuses on modeling the pneumatic brake system to estimate the pressure along the brake line in real time by employing two different methods: the lumped characteristics approach and an isothermal approach using the Navier–Stokes equation. The results from both models match with the ones from a commercial software, which is known to represent adequately the system's behavior on the field. Using processing time as the selection criteria, this work shows that the lumped characteristics method is the best choice to be employed in real-time simulations