２円筒試験機を用いた水潤滑条件における車輪／レール間の接線力特性の実験的評価

抄録

This paper describes the relationship between a tangential contact force and a slip ratio under various wet condition. In previous studies, the effect of difference in watering amount on the tangential contact force characteristics under wheel/rail contact condition has not been clarified quantitatively. In this study, in order to investigate the effects of various experimental condition such as rotational velocity of a test wheel, the amount of water, and contact pressure on the tangential contact force characteristics, a tangential contact force measurement experiment was conducted under the condition of maximum rotational velocity of 130km/h. As a result, if a small amount of water intervenes on the contact surface, we confirm that the tangential contact force under wet condition sharply becomes small about 30% or less of that under dry condition until the rotational velocity increases to 30km/h; also, we confirm that the faster the rotational velocity is the smaller the decrease in tangential force becomes. This tendency is the same under all contact pressure conditions and is qualitatively consistent with the actual phenomenon. Furthermore, it is clarified from the Polach’s proposed formula and an adhesive planning formula that laboratory experiment may be evaluated more severely than the actual phenomenon due to the difference in the amount of water film on the contact surface. This conclusion means that the tangential contact force characteristics of wheel/rail under wet condition can be estimated on laboratory experiments by correctly evaluating a water film on the contact surface between actual wheels and rails.