传统和旋转交错网格有限差分在双相介质中的模拟对比

The simulation contrast in the two-phase media between the traditional and rotated staggered grid

以Biot双相介质模型为背景,笔者推导了双相各向同性介质二维三分量一阶速度——应力弹性波方程方程,建立了各向同性双相介质波动方程的二维三分量有限差分格式。分别采用传统交错网格有限差分技术和旋转交错网格有限差分技术对均匀和非均匀双相各向同性介质进行了波场模拟。结果表明,旋转交错网格有限差分技术能够有效模拟双相各向同性介质中弹性波的传播情况;通过传统和旋转交错网格有限差分技术的对比,说明了旋转交错网格有限差分算法的稳定性更强,避免了插值带来的误差,是一种有效的地震波场模拟方法。

Starting with the model of the Biot two-phase media theory, the authors set up the 2D/3C velocity-stress elastic wave equation of the two-phase isotropie media and the finite difference time domain scheme through deduction.The wave field simulation is based on the two-phase homogeneous and inhomogeneous isotropic media using the traditional staggered-grid method and the rotated staggered- grid method.The results show that the rotated staggered grid difference scheme performs perfectly for the two-phase isotropic media.A comparison between rotated stagger-grid and traditional stagger-grid demonstrates that the finite difference algorithm of rotating stag- gered-grid is more stable and can avoid errors caused by interpolation, and hence the rotated staggered-grid difference scheme is a nu- merical simulation of seismic wave field method with a strong effectiveness.