Citation

Wilson N, Wu H, Tournay H, Urban C. Veh. Syst. Dyn. 2010; 48(Suppl 1): 487-503.

Copyright

(Copyright © 2010, Informa - Taylor and Francis Group)

DOI

10.1080/00423114.2010.490590

PMID

unavailable

Abstract

In North American freight service, lateral instability (vehicle hunting) is normally associated with light vehicles and high-speed operations. However, recent research conducted by Transportation Technology Center, Inc. (TTCI), under the Association of American Railroads' Strategic Research Initiatives Program, has shown that some new designs of heavy axle load freight cars are now susceptible to hunting when fully loaded at normal freight train operating speeds. Undesirable wheel/rail (W/R) contact conditions interacting with the car body dimensions and inertial parameters, combined with the characteristics of the suspensions, contribute to hunting. A summary of the investigation is presented here, which includes results of the vehicle tests, wheel and rail profile measurements and analyses, and NUCARS® 1 computer simulations. The effects of the vehicle suspension parameters and car body inertial parameters, combined with undesirable W/R contact patterns, are shown to have a significant influence on the vehicle's lateral stability performance, with potential consequences for damage to both vehicles and track, and increased potential for derailment.