Accurate Finite element simulation and experimental study of elastic wave propagation in a long cylinder under impact loading

Published

April 14, 2014

Author(s)

Steven P. Mates, A. V. Idesman

Abstract

An accurate solution for elastic wave propagation in a long axisymmetric elastic bar under impact loading is obtained using the new finite element technique proposed in our recent papers. In contrast to known numerical techniques, the new numerical approach quantifies and removes spurious high-frequency oscillations which may invalidate numerical results in impact loading simulations. The comparison of the accurate experimental results for the impact of striker and incident bars with the corresponding accurate numerical results allows us to explain some details of elastic wave propagation in long bars. For example, the analysis of the wave pulse at different locations from the impact face shows the presence of physical damping of some high frequencies during the pulse propagation. Due to the absence of very high frequencies in the obtained experimental results, the number of finite elements along the radial direction of the bar should be limited for the numerical description of these results. However, for the accurate numerical solution of the impact problem with zero physical damping, the number of elements in the radial direction should be large. By the comparison of the numerical and experimental data, we can accurately determine the longitudinal wave velocity from experiments. The accurate numerical solutions also allows the analysis of the uniformity of the different strain and velocity components across the radius at different distances from the impact face. The validity of some assumptions used in the 1-D theory for wave propagation in long bars is also checked by the use of the accurate numerical solution. We have also shown that the known disperion-correction technique used for the description of the shape of the wave pulse at different locations along the axisymmetric bar is inaccurate for the prediction of pulses close to the impact face.

Citation

Journal of the Mechanics and Physics of Solids

Pub Type

Journals

Keywords

elastic waves, finite elements, Hopkinson bar, impact loading, spurious oscillations

Citation

Mates, S. and Idesman, A. (2014), Accurate Finite element simulation and experimental study of elastic wave propagation in a long cylinder under impact loading, Journal of the Mechanics and Physics of Solids (Accessed April 18, 2024)