Three types of quasi-Trefftz functions for the 3D convected Helmholtz equation: construction and approximation properties

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Imbert-Gerard, Lise-Marie, Sylvand, Guillaume
Formato: Preprint
Publicado: 2022
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866914877902159872
author Imbert-Gerard, Lise-Marie
Sylvand, Guillaume
author_facet Imbert-Gerard, Lise-Marie
Sylvand, Guillaume
contents Trefftz methods are numerical methods for the approximation of solutions to boundary and/or initial value problems. They are Galerkin methods with particular test and trial functions, which solve locally the governing partial differential equation (PDE). This property is called the Trefftz property. Quasi-Trefftz methods were introduced to leverage the advantages of Trefftz methods for problems governed by variable coefficient PDEs, by relaxing the Trefftz property into a so-called quasi-Trefftz property: test and trial functions are not exact solutions but rather local approximate solutions to the governing PDE. In order to develop quassi-Trefftz methods for aero-acoustics problems governed by the convected Helmholtz equation, the present work tackles the question of the definition, construction and approximation properties of three families of quasi-Trefftz functions: two based on generalizations on plane wave solutions, and one polynomial. The polynomial basis shows significant promise as it does not suffer from the ill-conditioning issue inherent to wave-like bases.
format Preprint
id arxiv_https___arxiv_org_abs_2201_12993
institution arXiv
publishDate 2022
record_format arxiv
spellingShingle Three types of quasi-Trefftz functions for the 3D convected Helmholtz equation: construction and approximation properties
Imbert-Gerard, Lise-Marie
Sylvand, Guillaume
Numerical Analysis
Trefftz methods are numerical methods for the approximation of solutions to boundary and/or initial value problems. They are Galerkin methods with particular test and trial functions, which solve locally the governing partial differential equation (PDE). This property is called the Trefftz property. Quasi-Trefftz methods were introduced to leverage the advantages of Trefftz methods for problems governed by variable coefficient PDEs, by relaxing the Trefftz property into a so-called quasi-Trefftz property: test and trial functions are not exact solutions but rather local approximate solutions to the governing PDE. In order to develop quassi-Trefftz methods for aero-acoustics problems governed by the convected Helmholtz equation, the present work tackles the question of the definition, construction and approximation properties of three families of quasi-Trefftz functions: two based on generalizations on plane wave solutions, and one polynomial. The polynomial basis shows significant promise as it does not suffer from the ill-conditioning issue inherent to wave-like bases.
title Three types of quasi-Trefftz functions for the 3D convected Helmholtz equation: construction and approximation properties
topic Numerical Analysis
url https://arxiv.org/abs/2201.12993