Numerical simulation of wave propagation in elastic media faces the challenges arising from increasing demand of high resolution in modern 3-D imaging applications, which requires a balance between efficiency and accuracy in addition to being friendly to the distributed high-performance computing environment. In this paper, we propose a distributed local spline simulator (LOSS) for solving the wave equation. LOSS uses patched cubic B-splines to represent the wavefields and attains an accurate evaluation of spatial derivatives with linear complexity. In order to link the adjacent patches, a perfectly matched boundary condition is introduced to give a closure of local spline coefficients. Owing to the rapid decay property of the local wavelets in dual space, it can recover the global spline as accurately as possible only at the cost of local communications among adjacent neighbors. Several typical numerical examples, including 2-D acoustic wave equation and P- and S- wave propagation in 3-D homogenous or heterogenous media, are provided to validate its convergence, accuracy and parallel scalability.
翻译:弹性媒体对波浪传播进行数字模拟,面临在现代三维成像应用中对高分辨率需求日益增加而产生的挑战。 现代三维成像应用中,除了对分布式高性能计算环境有利外,还需要在效率和准确性之间保持平衡。 在本文中,我们建议用分布式本地样板模拟器(LOSS)来解决波方程。 LOSS使用补丁立方位B-spline来代表波场,并获得对具有线性复杂性的空间衍生物的准确评价。为了连接相邻的片段,引入了完全匹配的边界条件,以关闭本地样条系数。由于本地波段在双空的快速衰减特性,它只能以邻邻邻里当地通信的成本尽可能准确地恢复全球样条。提供了几个典型的数字例子,包括2-D声波方程式和P-S-波在3D同源或异源媒体中的传播,以验证其趋同性、准确性和平行的可缩度。