preliminary results on multi-body dynamic simulation of a new test rig for wheel-rail contact

the ability to perform rolling contact fatigue (rcf) experiments in wheel–rail material is provided by a new small–scale test rig, manifesting the actual dynamic behaviour of the railway system. in this paper, a multi-body dynamics (mbd) model is proposed, simulating the vibration behaviour of the prescribed rig. the new testing facility is modelled using a three-dimensional model of the vehicle-track system in mbd environment. this computer model, implemented in msc adams, represents the main components of the test rig, and evaluates their dynamic functionalities. the model is developed by coupling the mbd approach with the finite element method (fem). it provides the capability of performing time–domain simulations under various loading conditions. by applying the geometric profile of the rail under a sample of v-shape defect, dynamic responses of the test rig components are obtained. using a pulse load function, the rail defect is simulated by the imaginary motion of the wheel over the defected rail. performing a modal analysis using a mixed model of the mbd–fem, the main dynamic characteristics of the system are determined. the results of analysis show that, the mbd–fem simulation can only deal with low–frequency vibrations of the components, even if rail defects with relatively small wavelengths are applied as the source of dynamic excitations.