Introducing wheel-rail adhesion control into longitudinal train dynamics

Conventional longitudinal train dynamics (LTD) simulations apply several assumptions regarding wheel-rail adhesion but its control is not considered. This study linked an in-house LTD simulator to a commercial MBS dynamics simulator via the TCP/IP protocol. A heavy haul train with the configuration of 3 locomotives + 150 wagons was modelled. The wagons were modelled in the LTD simulator while the locomotives were modelled in the MBS simulator. The locomotive models were 3D models that included wheel-rail contact models and adhesion control models. Locomotives were simulated in parallel using three computer cores. Co-simulations with and without curve lubrication were conducted and compared with a conventional LTD simulation. Computing times with and without parallel computing were also compared. Compared with conventional LTD simulations, wheel-rail adhesion control generates evident differences for maximum traction forces, average train speeds, maximum in-train forces and force patterns. Parallel computing reduced the computing time by about 46%.