3-D NUMERICAL SIMULATION OF SUB-HARMONIC GENERATION PHENOMENON DUE TO CONTACT ACOUSTIC NONLINEARITY ON CRACK FACES

Abstract

This paper deals with nonlinear analysis of elastic wave scattering by cracks with contact boundary conditions in three-dimension (3-D). A generation mechanism of sub-harmonic waves due to contact acoustic nonlinearity has not been understood clearly. However, 2-D simulations of sub-harmonic generation by cracks with specific shape and arrangement have been conducted (Maruyama et al. 2015). Therefore, 3-D numerical simulations for similar models to the case of 2-D are performed. Through obtained numerical results, cause of the sub-harmonic generation phenomenon is discussed. The implicit Runge-Kutta based convolution quadrature time-domain boundary element method is used for precise and stable simulation.