Improving the track friendliness of a four-axle railway vehicle using an inertance-integrated lateral primary suspension

Abstract

Improving the track friendliness of a railway vehicle can benefit the railway industry significantly. Rail surface damage in curves can be reduced by using vehicles with a lower Primary Yaw Stiffness (PYS); however, this can reduce high-speed stability and worsen ride comfort. Previous studies have shown that this trade-off between track friendliness and passenger comfort can be successfully combated by using an inerter in the primary suspension; however, these utilise simplified vehicle models, contact models, and track inputs. Considering a realistic four-axle passenger vehicle model, this paper investigates the extent to which the PYS can be reduced with inertance-integrated primary lateral suspensions without increasing root-mean-square (RMS) carbody lateral accelerations. The vehicle model, with these enhanced suspensions, has been created in VAMPIRE${}^{\circledR }$,  with the dynamics being captured over a range of vehicle velocities and equivalent conicities. Based on systematic optimisations using network-synthesis theory, several beneficial inertance-integrated configurations are identified, and the PYS can be reduced by up to 47% compared to the default vehicle (a potential Network Rail Variable Usage Charge saving of 26%), without increasing RMS carbody lateral accelerations. Further simulations are performed to investigate the vehicle's performance in curve transitions and when subject to one-off peak lateral track irregularities.

Keywords:

• Inertance-integrated networks
• suspension
• vibration
• railway vehicle

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors would like to thank Engineering and Physical Sciences Research Council (EPSRC) (Grant Reference: EP/P013546/1) and the Rail Safety and Standards Board (RSSB) for funding this research.