Open AccessA hybrid calculation technique of the Indirect Boundary Element Method and the analytical solutions for three‐dimensional problems of topography
Author(s) -
Yokoi Toshiaki,
SénchezSesma Francisco, J.
Publication year - 1998
Publication title -
geophysical journal international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0956-540X
DOI - 10.1046/j.1365-246x.1998.1331466.x
Subject(s) - boundary element method , discretization , boundary (topology) , gaussian , mathematical analysis , surface (topology) , truncation (statistics) , mathematics , domain (mathematical analysis) , numerical analysis , method of fundamental solutions , element (criminal law) , gaussian integral , free surface , boundary value problem , boundary knot method , finite element method , geometry , physics , mechanics , statistics , quantum mechanics , thermodynamics , political science , law
We present a new approach of the Indirect Boundary Element Method (IBEM) for 3‐D topographic problems which can be used to deal with an infinitely spread free surface owing to the introduction of a reference solution, that is the analytical solution for the half‐space with a flat free surface. This approach is an efficient countermeasure for the non‐physical waves owing to the domain truncation which contaminates the computed results in the ordinary approach. Theoretical consideration shows that this newly proposed approach is a higher‐grade approximation than some existing ones and achieves a higher efficacy and accuracy than those of existing ones. The discretization of the resulting boundary integral equation for this formulation is carried out with triangular elements. Their contributions to the solution are calculated by Gaussian numerical integration except in the case where the wavefield is evaluated on the source element itself. For this case, we present an analytical formula based on the reasonable assumption that the elements are much smaller than the wavelengths appearing in the calculation. Several numerical examples used for validation show acceptably precise results.