Strain-rate-dependent model for elastoplastic normal repeated impacts of a sphere on a beam

Abstract

Normal repeated impacts are common phenomena in machine dynamics. When repeated impacts occur, the plastic deformation from previous collisions can affect the behavior of following collisions. To increase the efficiency of calculation and analysis, in this paper a hybrid model (analytical-numerical model) is developed to analysis of the impact transient response of a flexible beam, driven by normal low-velocity repeated transverse impact of a sphere. The hybrid model include a refined contact model and a combined discretization model. The dependence of material strain rate is considered in both the sub-models. During each impact, the sphere strikes the beam at the same position. In subsequent impacts the accumulated contact plastic deformation of the beam remains. The transient responses of repeated impacts of beam simulated by the hybrid model is validated using experimental test and 3D finite element (FE) model. The comparisons of the results of hybrid model with the results of finite element (FE) analysis and experimental show that the hybrid model is valid which can accurately predict the transient response of normal repeated impacts. The calculating efficiency comparison between hybrid model and the FE model shows that the hybrid model is suitable and highly efficient for parametric study.