Analysis of vertical dynamic wheel/rail interaction caused by polygonal wheels on high-speed trains

• A vehicle-track coupled model is adopted to simulate wheel/rail interaction.
• The polygonal wheel causes obvious fluctuations of wheel/rail force at high speeds.
• The derivative of radial deviation reflects dynamic wheel/rail contact force.
• The dynamic wheel/rail interaction is categorized into three main forms.
• Short-wavelength harmonics of the polygonal wheel intensify rail vibration.

In order to investigate vertical dynamic wheel/rail interaction resulting from a polygonal wheel at high-speeds, a vertical vehicle-track coupled dynamics model is adopted. The measured results from German ICE polygonal wheels are utilized as multi-harmonic excitations. Two types of out-of-round wheels, the periodic and the non-periodic, are simulated and compared. The dynamic wheel/rail interaction induced by different harmonics is analyzed in both time and frequency domains. Results demonstrate that the polygonal wheel will result in considerable fluctuation of wheel/rail contact force. Derivative of wheel radial deviations can effectively reflect dynamic wheel/rail contact force at train speeds above 300 km/h. Dynamic wheel/rail load becomes more sensitive to high order harmonics with increased speeds. Influence of the out-of-round wheel on vehicle system is mainly related to the wheelset vibration. Short-wavelength components of the polygonal wheel stimulate high-frequency vibrations of rails and sleepers.