【摘 要】
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We present high order accurate numerical methods for the wave equation that combines efficient Hermite methods with geometrically flexible discontinuous Galerkin methods by using overset grids.Near boundaries we use thin boundary fitted curvilinear grids
【机 构】
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Department of Mathematics and Statistics,The University of New Mexico,1 University of New Mexico,MSC
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We present high order accurate numerical methods for the wave equation that combines efficient Hermite methods with geometrically flexible discontinuous Galerkin methods by using overset grids.Near boundaries we use thin boundary fitted curvilinear grids and in the volume we use Cartesian grids so that the computational complexity of the solvers approaches a structured Cartesian Hermite method.Unlike many other overset methods we do not need to add artificial dissipation but we find that the built-in dissipation of the Her-mite and discontinuous Galerkin methods is sufficient to maintain the stability.By numeri-cal experiments we demonstrate the stability,accuracy,efficiency,and the applicability of the methods to forward and inverse problems.
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