A nonlinear state-dependent model for vibrations excited by roughness in rolling contacts

Investigation of the Dynamic Properties of Railway Tracks using a Model for Calculation of Generation of Wheel/Rail Noise

“…It can be calculated, according to section 1.2.4, in the time-domain with the rail/wheel simulation program [11], and the nonlinear state-dependent rolling contact model [12].…”

“…In an iterative manner for each time-step, the wheel and rail displacements as well as the contact force are determined by balancing the geometric relation stated above with the state-dependent contact force expression (11) where k c (δ) is the state-dependent contact stiffness and are the state-dependent line texture heights. Definitions and methodology of the state-dependent force formulation, which here is applied to the wheel-rail contact, was previously presented in [12]. In summary, the widely used Hertzian contact stiffness and the linearized contact filter are replaced by state-dependent contact stiffness and contact filters which vary with the relative displacement of the wheel and the rail.…”

“…Contact force calculation in the frequency domain It is shown in [8], in a way similar to the TWINS simulation program, that a linear approximation for the contact force spectrum between rail and wheel can be written (12) where v is the train speed, is the roughness spectrum of the running surface of the rail, is the roughness spectrum of the running surface of the wheel, and is the contact filter. means the linearized Hertzian contact spring stiffness, is the vertical rail receptance, and is the radial receptance of the wheel.…”

“…Instead, a set of roughness data of the wheel and the rail in short wavelengths from [15] is used as reference since the values correspond well with the roughness levels and the decaying slopes presented in [13,14] in a region of wavelengths where the two data sets overlap. Using the short wavelength roughness from [15] together with a method to generate surface data from line texture data (see [12]), surface roughness is generated and superimposed on the geometrical shape of the wheel and the rail.…”

Thermal and dynamic behaviors of wheel/rail contact system considering thermal-mechanical coupling effects

“…Xiaolu Cui. et al [5], Oskar E. Lundberg et al [6] and Chao Zou et al [7] researched the vibrations and noise of wheel/rail under different contact states. And the suggestions to reduce the vibration and noise of wheel/rail system are given.…”