One of the nagging problems which appears in the application of discrete solution methods to wave propagation problems is the presence of reflections or wraparound from the boundaries of the numerical mesh. In this paper we describe a scheme for the elimination of these unwanted events which can be applied to a wide class of wave equations and numerical methods. The scheme is first presented as an empirical approach based on a gradual elimination of wave amplitudes along the bondaries of the numerical grid. However, in order to apply the method to implicit and semi-implicit schemes which do not use explicit time stepping, the absorbing boundary condition is rederived and cast in the form of a modified wave equation. This derivation gives the additional benefit of the ability to evaluate the effectiveness of the absorbing boundary a priori, and adjust its parameters without having to make costly computer runs. The absorbing boundary condition is demonstrated with examples from acoustic and elastic wave propagation with the Fourier solution method.
|Number of pages||2|
|State||Published - 1984|
|Event||1984 Society of Exploration Geophysicists Annual Meeting, SEG 1984 - Atlanta, United States|
Duration: 2 Dec 1984 → 6 Dec 1984
|Conference||1984 Society of Exploration Geophysicists Annual Meeting, SEG 1984|
|Period||2/12/84 → 6/12/84|