Wave propagation across fluid-solid interfaces:a grid method approach
会议名称：《中国科学院地质与地球物理研究所2004学术年会》
会议日期：2004年
学科分类：081801[工学-矿产普查与勘探] 081802[工学-地球探测与信息技术] 08[工学] 0818[工学-地质资源与地质工程]
关 键 词：finite difference grid method marine seismic modelling sea bottom topography
摘 要：This paper presents a new numerical technique for modelling wave propagation in media with both fluid(acoustic) and solid(elastic) regions,as found for instance in a marine seismic case. The scheme can correctly satisfy the fluid-solid interface conditions and accurately models the arbitrary interface *** work is an extension of the grid method,which is able to model wave propagation in heterogeneous solid(elastic) media with arbitrary surface topography and irregular *** scheme is developed by formulating the problem in terms of displacements in elastic regions and pressure in acoustic regions with an explicit boundary between *** fluid-solid interface conditions on this explicit boundary are implemented by introducing an integral approach to the fluid-solid interface *** solution in terms of pressure in acoustic regions together with this integral approach means that no extra computational cost is needed to implement the fluid-solid interface conditions for a complex geometry,instead of resulting in additional computations as with the spectralelement, finite-element or finite-difference *** this paper an acoustic grid method is developed to solve the acoustic problem inside the fluid,and the(elastic) grid method,which is improved based on a parsimonious staggered-grid scheme,is used to solve the elastic problem inside the *** numerical dispersion and stability criteria for the acoustic grid method are discussed in *** with an analytical solution demonstrates that the proposed scheme handles the fluid-solid interface conditions *** of wave propagation in a mixed fluid/solid model with both weak and strong sinusoidal fluid-solid interfaces illustrate the suitability of the proposed scheme for modelling wave propagation across fluid-solid interfaces with complex geometries.