{ "id": "1608.01944", "version": "v1", "published": "2016-08-05T17:22:28.000Z", "updated": "2016-08-05T17:22:28.000Z", "title": "Weight-adjusted discontinuous Galerkin methods: wave propagation in heterogeneous media", "authors": [ "Jesse Chan", "Russell J. Hewett", "T. Warburton" ], "comment": "Submitted to SISC", "categories": [ "math.NA" ], "abstract": "Time-domain discontinuous Galerkin (DG) methods for wave propagation require accounting for the inversion of dense elemental mass matrices, where each mass matrix is computed with respect to a parameter-weighted L2 inner product. In applications where the wavespeed varies spatially at a sub-element scale, these matrices are distinct over each element, necessitating additional storage. In this work, we propose a weight-adjusted DG (WADG) method which reduces storage costs by replacing the weighted L2 inner product with a weight-adjusted inner product. This equivalent inner product results in an energy stable method, but does not increase storage costs for locally varying weights. A-priori error estimates are derived, and numerical examples are given illustrating the application of this method to the acoustic wave equation with heterogeneous wavespeed.", "revisions": [ { "version": "v1", "updated": "2016-08-05T17:22:28.000Z" } ], "analyses": { "keywords": [ "weight-adjusted discontinuous galerkin methods", "wave propagation", "heterogeneous media", "l2 inner product", "mass matrix" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }