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Title: High order weight‐adjusted discontinuous Galerkin methods for wave propagation on moving curved meshes
Abstract

This article presents high order accurate discontinuous Galerkin (DG) methods for wave problems on moving curved meshes with general choices of basis and quadrature. The proposed method adopts an arbitrary Lagrangian–Eulerian formulation to map the wave equation from a time‐dependent moving physical domain onto a fixed reference domain. For moving curved meshes, weighted mass matrices must be assembled and inverted at each time step when using explicit time‐stepping methods. We avoid this step by utilizing an easily invertible weight‐adjusted approximation. The resulting semi‐discrete weight‐adjusted DG scheme is provably energy stable up to a term that (for a fixed time interval) converges to zero with the same rate as the optimal error estimate. Numerical experiments using both polynomial and B‐spline bases verify the high order accuracy and energy stability of proposed methods.

 
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Award ID(s):
1712639 1719818
NSF-PAR ID:
10445151
Author(s) / Creator(s):
 ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
International Journal for Numerical Methods in Engineering
Volume:
122
Issue:
23
ISSN:
0029-5981
Page Range / eLocation ID:
p. 7101-7133
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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