2020 Volume 76 Issue 2 Pages I_173-I_181
In this study, the H -matrix method is applied to a harmonic balance-boundary element method (HB-BEM). The HB-BEM is a numerical method which deals with steady-state wave scattering by a crack with contact acoustic nonlinearity. The HB-BEM requires high computational costs because it is necessary to simultaneously solve boundary integral equations for several frequencies which are coupled by nonlinear boundary conditions. Since the Newton method is used in the process of solving the nonlinear equations,the computational time for inversion of the Jacobi matrix is predominant. The inversion process is accelerated by means of the H -matrix method, which allows us to use LU decomposition because the Jacobi matrix is ill-conditioned. Through numerical results, the in fluence due to the arrangement of matrix on the acceleration is examined. The computational costs versus the number of unknown variables are also investigated.
