(Continued from Proc. Instn. Mech. Engrs. Part F, 1997, Vol. 211, F1, 11 - 26) The linearized dynamic models for the conformal contact of a wheel and rail presented before have been used to calculate the dynamic response to a predescribed sinusoidal ripple on the railhead. Three models have been developed: single-point contact with low or high conformity, and two-point contact. The input comprises rail a normal displacement Delta ei.omega.t together with a rotation Psi ei.omega.t applied to the railhead. The output comprises rail displacements and forces, contact creepages and forces, and frictional energy dissipation. According to the Frederic-Valdivia hypothesis, if this last quantity has a component in phase with the input ripple, the amplitude of the ripple will be attenuated, and vice versa. Over the most of the frequency range, a pure displacement input (Psi = 0) was found to give rise, predominantly, to a normal force at the railhead. A purely rotational input (Delta = 0) caused a single point of contact to oscillate across the railhead or, in the case of two-point contact, to give rise to fluctuating out-of-phase forces at the two points. The general tenor of behaviour revealed by the three models was similar: frictional energy dissipation, and hence wear, increases conformity and is usually of such a phase as to suppress corrugation growth. Thus the association, found on the Vancouver mass transit system, of corrugations with the development of close conformity between wheel and rail profiles must arise from some feature of the system not included in the present models.
Wheel-rail dynamics with closely conformal contact. Part 2: forced response, results and conclusions
Modellentwicklung zur Rad-Schiene-Dynamik mit streng konformem Kontaktverhalten. Teil 2: Riffelbildung, Reibung, Verschleiß. Erzwungenes Antwortverhalten, Ergebnisse und Schlußfolgerungen
1997
14 Seiten, 10 Bilder, 2 Tabellen, 5 Quellen
Aufsatz (Zeitschrift)
Englisch
Wheel-rail dynamics with closely conformal contact Part 2: Forced response, results and conclusions
SAGE Publications | 1997
|Wheel-rail dynamics with closely conformal contact Part 2: Forced response, results and conclusions
Online Contents | 1997
|Wheel-rail dynamics with closely conformal contact Part 1: Dynamic modelling and stability analysis
Online Contents | 1997
|Wheel-rail dynamics with closely conformal contact Part 1: Dynamic modelling and stability analysis
SAGE Publications | 1997
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