The Ultra Weak Variational Formulation (UWVF) of the Helmholtz equation provides a variational framework suitable for discretization using plane wave solutions of an appropriate adjoint equation. Currently convergence of the method is only proved on the boundary of the domain. However substantial computational evidence exists showing that the method also converges throughout the domain of the Helmholtz equation. In this paper we exploit the fact that the UWVF is essentially an upwind discontinuous Galerkin method to prove convergence of the solution in the special case where there is no absorbing medium present. We also provide some other estimates in the case when absorption is present, and give some simple numerical results to test the estimates. We expect that similar techniques can be used to prove error estimates for the UWVF applied to Maxwell's equations and elasticity.
@article{M2AN_2008__42_6_925_0, author = {Buffa, Annalisa and Monk, Peter}, title = {Error estimates for the ultra weak variational formulation of the Helmholtz equation}, journal = {ESAIM: Mathematical Modelling and Numerical Analysis - Mod\'elisation Math\'ematique et Analyse Num\'erique}, volume = {42}, year = {2008}, pages = {925-940}, doi = {10.1051/m2an:2008033}, mrnumber = {2473314}, zbl = {1155.65094}, language = {en}, url = {http://dml.mathdoc.fr/item/M2AN_2008__42_6_925_0} }
Buffa, Annalisa; Monk, Peter. Error estimates for the ultra weak variational formulation of the Helmholtz equation. ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique, Tome 42 (2008) pp. 925-940. doi : 10.1051/m2an:2008033. http://gdmltest.u-ga.fr/item/M2AN_2008__42_6_925_0/
[1] Dispersive and dissipative properties of discontinuous Galerkin methods for the wave equation. J. Sci. Comput. 27 (2006) 5-40. | MR 2285764 | Zbl 1102.76032
, and ,[2] Unified analysis of discontinuous Galerkin methods for elliptic problems. SIAM J. Numer. Anal. 39 (2002) 1749-1779. | MR 1885715 | Zbl 1008.65080
, , and ,[3] Stability and convergence of the method of fundamental solutions for Helmholtz problems on analytic domains. J. Comp. Phys. (to appear). | MR 2435440 | Zbl pre05303096
and ,[4] A GSVD formulation of a domain decomposition method for planar eigenvalue problems. IMA J. Numer. Anal. 27 (2007) 451-478. | MR 2337576 | Zbl pre05173878
,[5] Application d'une nouvelle formulation variationnelle aux équations d'ondes harmoniques. Problèmes de Helmholtz 2D et de Maxwell 3D. Ph.D. thesis, Université Paris IX Dauphine, France (1996).
,[6] Application of the ultra-weak variational formulation of elliptic PDEs to the 2-dimensional Helmholtz problem. SIAM J. Numer. Anal. 35 (1998) 255-299. | MR 1618464 | Zbl 0955.65081
and ,[7] Using plane waves as base functions for solving time harmonic equations with the Ultra Weak Variational Formulation. J. Comput. Acoustics 11 (2003) 227-238. | MR 2013687
and ,[8] Sharp regularity coefficient estimates for complex-valued acoustic and elastic Helmholtz equations. Math. Models Methods Appl. Sci. 16 (2006) 139-160. | MR 2194984 | Zbl 1134.35317
and ,[9] A comparison of two Trefftz-type methods: The ultraweak variational formulation and the least-squares method, for solving shortwave 2-D Helmholtz problems. Int. J. Numer. Meth. Eng. 71 (2007) 406-432. | MR 2332814
and ,[10] Plane wave discontinuous Galerkin methods. Preprint NI07088-HOP, Isaac Newton Institute Cambride, Cambridge, UK, December (2007) http://www.newton.cam.ac.uk/preprints/NI07088.pdf.
, and ,[11] Boundary Methods: an Algebraic Theory. Pitman (1984). | MR 766561 | Zbl 0549.35004
,[12] The perfectly matched layer for the ultra weak variational formulation of the 3D Helmholtz equation. Int. J. Numer. Meth. Eng. 61 (2004) 1072-1092. | MR 2094680 | Zbl 1075.76648
, and ,[13] Computational aspects of the Ultra Weak Variational Formulation. J. Comput. Phys. 182 (2002) 27-46. | MR 1936802 | Zbl 1015.65064
, and ,[14] The Ultra Weak Variational Formulation for elastic wave problems. SIAM J. Sci. Comput. 25 (2004) 1717-1742. | MR 2087333 | Zbl 1093.74028
, , and ,[15] Solving Maxwell's equations using the Ultra Weak Variational Formulation. J. Comput. Phys. 223 (2007) 731-758. | MR 2319231 | Zbl 1117.78011
, and ,[16] On generalized finite element methods. Ph.D. thesis, University of Maryland, College Park, USA (1995).
,[17] The partition of unity finite element method: Basic theory and applications. Comput. Meth. Appl. Mech. Eng. 139 (1996) 289-314. | MR 1426012 | Zbl 0881.65099
and ,[18] A least squares method for the Helmholtz equation. Comput. Meth. Appl. Mech. Eng. 175 (1999) 121-136. | MR 1692914 | Zbl 0943.65127
and ,[19] Least-squares Trefftz-type elements for the Helmholtz equation. Int. J. Numer. Meth. Eng. 41 (1998) 831-849. | MR 1607804 | Zbl 0909.76052
,[20] Three-dimensional discontinuous Galerkin elements with plane waves and Lagrange multipliers for the solution of mid-frequency Helmholtz problems. Int. J. Numer. Meth. Eng. 66 (2006) 796-815. | MR 2219901 | Zbl 1110.76319
and ,[21] Ein gegenstück zum Ritz'schen verfahren, in Proc. 2nd Int. Congr. Appl. Mech., Zurich (1926) 131-137. | JFM 52.0483.02
,