1 research outputs found
Elastic wave propagation in curvilinear coordinates with mesh refinement interfaces by a fourth order finite difference method
We develop a fourth order accurate finite difference method for the three
dimensional elastic wave equation in isotropic media with the piecewise smooth
material property. In our model, the material property can be discontinuous at
curved interfaces. The governing equations are discretized in second order form
on curvilinear meshes by using a fourth order finite difference operator
satisfying a summation-by-parts property. The method is energy stable and high
order accurate. The highlight is that mesh sizes can be chosen according to the
velocity structure of the material so that computational efficiency is
improved. At the mesh refinement interfaces with hanging nodes, physical
interface conditions are imposed by using ghost points and interpolation. With
a fourth order predictor-corrector time integrator, the fully discrete scheme
is energy conserving. Numerical experiments are presented to verify the fourth
order convergence rate and the energy conserving property