Abstract: A dynamic substructure model is presented to investigate the propagations of the transient waves generated by a beam impacting against a rod. The dynamic governing equation is derived in physical coordinates and modal coordinates. Both the adhesive contact model and the local contact model of uniaxial compression are applied to simulate contact constraints. By the comparison with the theoretical solution, the present dynamic substructure model is shown to be convergent in numerical calculation and of high numerical precision. The numerical results of the bending waves along the beam and the longitudinal waves along the rod have proven that the dynamic substructure model is valid in depicting wave propagation characteristics, such as wave propagation, wave reflection and wave interaction. Furthermore, the model is applied to simulate the bending and longitudinal waves travelling across the contact constraint, and the simulations illustrate that the impact force response is influenced significantly by the wave propagations of both the bending wave and the longitudinal wave. It might be an important reason of the complicated variations of impact force response.

Key words: Beam, Dynamic substructure model, Impact, Impact force, Rod, Wave