ASA 125th Meeting Ottawa 1993 May

2pNS1. The generation of high-speed train noise from roughness.

Paul J. Remington

Jonathon Webb

Bolt Beranek and Newman, Inc., 70 Fawcett St., Cambridge, MA 02138

The forces generated in the contact area between railroad wheels and rails due to small scale roughness has been estimated using three analytical techniques: a simple average of the roughness, a point reacting spring model, and a full elastic interaction model. Roughness data measured in a number of parallel tracks in the rolling direction on partially worn wheels and rails was used in these three models. The forces estimated by all three analytical techniques were remarkably similar in the range of wavelengths important for noise generation from high-speed (200-to 400-km/h) trains. Wave-number decomposition of the roughness data has shown it to be bandlimited in the direction transverse to rolling, a result consistent with the similarity in the predictions of the three analytical techniques. The influence of wheel and rail profile and high roughness amplitudes at low wave number will be discussed.