A fundamental study on fine unevenness and tangent force on wheel tread of railway vehicle (relations between environmental condition and tangent force characteristics with a two-disk rolling machine)

Abstract

This paper presents the laboratory experimental results in relation to tangent force between a wheel and a rail under different environmental conditions. In the experiments, we used two types of cylindrical test specimens (with / without fine unevenness on contact surface) assuming actual wheels, and investigated the relation of tangent force to the cases of with / without fine unevenness on contact surface under the conditions of different environmental temperature and relative humidity. Consequently, under the conditions of without fine unevenness on the contact surface of a test specimen, it showed that there is a tendency in the tangent force which turned out low whence relative humidity is over 60%, regardless of environmental temperature. However, on the conditions which have fine unevenness on the contact surface of a test specimen, we could not observe the effect of environmental temperature and relative humidity on the tangent force. In addition, running stability analysis of railway vehicle was carried out for the cases of with / without fine unevenness on wheel tread of railway vehicle under the condition of different relative humidity. As a result, it was shown that the critical hunting velocity under the condition of without fine unevenness becomes low while increasing relative humidity. © 2011 The Japan Society of Mechanical Engineers.