Frequency-Dependent Nonreflecting Boundary for Absorbing Lamb Waves Based on Lysmer and Kuhlemeyer Absorbing Boundary

Abstract

This paper reports two nonreflecting boundaries based on the Lysmer and Kuhlemeyer (L-K) absorbing boundary, respectively for absorbing symmetric and antisymmetric Lamb wave, which compensate for the weakness of the L-K absorbing boundary in the application for absorbing Lamb waves at the structural boundary. In this paper, the accurate and approximate formulas of the coefficients of the nonreflecting boundary for symmetric and antisymmetric Lamb waves are obtained by theoretical deduction based on the L-K method. The effectiveness and robustness of these nonreflecting boundaries are verified by comparing with the conventional L-K absorbing boundary in simulation cases. In addition, the limitations of these nonreflective boundaries are discussed.