2018_EJRNL_PP_AJAY_MALKOTI_1.pdf
Terbatas  
» Gedung UPT Perpustakaan
Terbatas  
» Gedung UPT Perpustakaan
The accuracy of a numerical derivative has a significant effect on any numerical simulation. Long
stencils can provide high accuracy as well as reduce the numerical anisotropy error. However,
such a long stencil demands extensive computational resources and with their growing size, such
derivatives may become physically non-realistic since contributions from very far offset whereas
the derivative is local in nature. Further, the application of such long stencils at boundary points
may introduce errors. In this paper, we present a very efficient, accurate and compact size
numerical scheme for acoustic wave propagation using implicit finite difference operator, which
utilizes a lesser number of points to estimate derivatives in comparison to the conventional central
difference derivative operator. The implicit derivative operator, despite its several advantages, is
generally avoided due to its high computational cost. Therefore in this paper, we discuss a method
which can dramatically reduce the computational cost of this scheme to almost half. This strategy
is useful particularly for 2D and 3D case. Spectral characteristics of the derivative operator and the
numerical scheme are compared with several other central difference schemes. We have also
demonstrated an application of this scheme for seismic wave propagation in 2D and 3D acoustic
media.