Kosuke Matsumoto

A proposal of wheel/rail contact model for friction control

Controlling the friction between wheel and rail is direct and very effective measures to improve the curiving performances of railway trucks, because the curving performances depend much on friction characteristics Authors have proposed a method, “fnction control”, which utilizes friction modifier (KELTRACK™ HPF) with onboard spraying system With the method, not only friction coefficient, but also fuction characteristics can be controlled as expected In this study, MBD simulation is very valuable tool to foresee the effect of the control in advance of experiment with real car And the creep characteristics of wheel/rail contact with the fuction modifier takes very important role in the simulation In this paper, authors propose a theoretical model of wheel/rail contact condition considering the creep characterstics of friction modifier, which is derived the application of principle tribological theories

The Optimum Design of an Onboard Friction Control System Between Wheel and Rail in a Railway System for Improved Curving Negotiation

In the subway lines of Tokyo (Tokyo Metro), there are many tight curves that may cause squeal noise, excessive rail/wheel wear and rail corrugation. To solve these serious problems, an onboard friction control system with friction modifier has been developed by the authors and has been equipped on commercial trains as a trial. With this system, the balance between supply and consumption of friction modifier is very important. That is to say, in order to obtain the maximum effect of friction control steadily, it is natural that an appropriate quantity of friction modifier should be required. In this report, results of experiments with a two-roller-rig testing machine, and analysis of the observed data in commercial train tests are introduced. In addition, the authors considered the method to realize the appropriate balance between supply and consumption of friction modifier.

Wheel/rail friction control with feedback system detecting yaw moment of wheelset

In the subway lines of Tokyo Metro, there are many tight curves that may cause squeal noise, excessive rail/wheel wear and also rail corrugation. To solve these serious problems, an onboard friction control system has been developed by the authors and has been equipped on some commercial trains [Y. Suda, H. Komine, T. Iwasa, M. Tomeoka, K. Matsumoto, N. Ubukata, M. Tanimoto, M. Nakata, and T. Nakai, Improvement of curving performance with friction control between wheel and rail, The 17th IAVSD Symposium Poster Session, Lyngby, Denmark, August, 2001; Y. Suda, H. Komine, T. Iwasa, T. Fujii, Tomeoka, K. Matsumoto, N. Ubukata, M. Tanimoto, M. Nakata, and T. Nakai, Experiment and analysis for improvement of curving performance with friction control between wheel and rail, Veh. Syst. Dynam. 41(Suppl.) (2004), pp. 507–516.]. With the system, in order to obtain the enough effect of friction control steadily, it is natural that an appropriate quantity of friction modifier should be required [K. Matsumoto, Y. Suda, T. Fujii, H. Komine, M. Tomeoka, Y. Sato, T. Nakai, M. Tanimoto, and Y. Kishimoto, The optimum design of an onboard friction control system between wheel and rail in a railway system for improved curving negotiation, Veh. Syst. Dynam. 44(Suppl.) (2006), pp. 531–540]. On such a viewpoint, the authors propose a new friction control system with the detection of yaw moment acting on the running wheelset. In this paper, first, outline of conventional feed-forward control system is introduced; secondly, the concept of feedback friction control system is presented considering the results of the multi-body dynamics simulations, and finally some field running test results of the developed system are discussed.

Correlation between Effects of Friction Control and Quantity of Supply

Controlling the friction between wheel and rail is direct and very effective measures to improve the curving performances of railway trucks, because the curving performances of truck depend much on friction characteristics. Authors have proposed a method, “friction control”, which utilizes friction modifier (KELTRACKTM HPF) with onboard spraying system. With the method, not only friction coefficient, but also friction characteristics are able to he controlled as expected. In this paper, results of fundamental experiments are reported which play an important role to realize the new method.

Evaluation of Friction Control Between Wheel/Rail by Simulation and Experiment

Controlling the friction between wheel and rail is direct and very effective measures to improve the curving performances of railway trucks, because the curving performances depend much on friction characteristics. Authors have proposed a method, “friction control”, which utilizes friction modifier (specialized for wheel / rail contact) with onboard spraying system. With the method, not only friction coefficient, but also friction characteristics can be controlled as expected. In this paper, authors introduce a very interesting finding that revolution difference between leading and trailing axles depends on effectiveness of friction control which was found in the procedure of simulation. In order to certify the reality of the finding, authors carried out experiments with 1/10-scaled model vehicle. And as the result, the potential use of revolution difference between the leading and trailing as a means to evaluate effectiveness of friction control was recognized.Copyright