Estimation of the dispersion error in the numerical wave number of standard and stabilized finite element approximations of the Helmholtz equation

An estimator for the error in the wave number is presented in the context of finite element approximations of the Helmholtz equation. The proposed estimate is an extension of the ideas introduced in Steffens and D'iez (Comput. Methods Appl. Mech. Engng 2009; 198:1389–1400). In the previous work...

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Detalles Bibliográficos
Autores: Steffens, Lindaura Maria, Parés Mariné, Núria|||0000-0002-2914-9904, Díez, Pedro|||0000-0001-6464-6407
Tipo de recurso: artículo
Fecha de publicación:2011
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/117188
Acceso en línea:https://hdl.handle.net/2117/117188
https://dx.doi.org/10.1002/nme.3104
Access Level:acceso abierto
Palabra clave:Waves
Numerical analysis
wave problems
Helmholtz equation
a posteriori error estimation
error estimation of wave number
dispersion/pollution error
stabilized methods
Ones
Anàlisi numèrica
Classificació AMS::74 Mechanics of deformable solids::74J Waves
Classificació AMS::65 Numerical analysis::65G Error analysis and interval analysis
Àrees temàtiques de la UPC::Matemàtiques i estadística::Anàlisi numèrica::Mètodes numèrics
Àrees temàtiques de la UPC::Matemàtiques i estadística::Matemàtica aplicada a les ciències
Descripción
Sumario:An estimator for the error in the wave number is presented in the context of finite element approximations of the Helmholtz equation. The proposed estimate is an extension of the ideas introduced in Steffens and D'iez (Comput. Methods Appl. Mech. Engng 2009; 198:1389–1400). In the previous work, the error assessment technique was developed for standard Galerkin approximations. Here, the methodology is extended to deal also with stabilized approximations of the Helmholtz equation. Thus, the accuracy of the stabilized solutions is analyzed, including also their sensitivity to the stabilization parameters depending on the mesh topology. The procedure builds up an inexpensive approximation of the exact solution, using post-processing techniques standard in error estimation analysis, from which the estimate of the error in the wave number is computed using a simple closed expression. The recovery technique used in Steffens and Díez (Comput. Methods Appl. Mech. Engng 2009; 198:1389–1400) is based in a polynomial least-squares fitting. Here a new recovery strategy is introduced, using exponential (in a complex setup, trigonometric) local approximations respecting the nature of the solution of the wave problem.