地下空洞地震波场的旋转交错网格有限差分数值模拟[EB/OL]
北京：中国科技论文在线
） 摘要： 将真空法和旋转交错网格相结合实现了地下空洞高阶旋转交错网格波场数值模拟
） Abstract： We combined the improved vacuum formulation and the rotated staggered grid finite difference method to implement the high order rotated staggered finite difference elastic wave-field simulation at the presence of underground cavities
Our method overcame the defect of rotated staggered finite difference when modeling the free surface condition which is only stable at second order spatial FD operators, through the comparison with existing vacuum formulation testifies our methods accuracy and stability
The perfectly Matched Layer (PML) absorbing boundary condition is applied to decrease the reflection from the edges of the numerical model
Different seismograms are calculated with models without voids and models contain voids with different size and depth under different source wavelet frequency
The effects of different cavity size and depth and the source wavelet frequency are evaluated from the snapshots and seismograms with and without the cavity
Keywords： rotated staggered grid
模拟了不同模型参数组合情况下的地震波传播以及地震波与地下空洞的相互作用
分析了地震波在地下存在空洞时的传播特征以及震源子波频率、地下空洞大小和埋深对地表地震记录的影响
克服了旋转交错网格在模拟自由边界条件时只在空间二阶差分时稳定的不足
通过和已有普通交错网格下改进的真空法对比
