[HTML][HTML] Wavenumber-explicit convergence of the hp-FEM for the full-space heterogeneous Helmholtz equation with smooth coefficients

D Lafontaine, EA Spence, J Wunsch - Computers & Mathematics with …, 2022 - Elsevier
A convergence theory for the hp-FEM applied to a variety of constant-coefficient Helmholtz
problems was pioneered in the papers [35],[36],[15],[34]. This theory shows that, if the …

For Most Frequencies, Strong Trapping Has a Weak Effect in Frequency‐Domain Scattering

D Lafontaine, EA Spence… - Communications on Pure …, 2021 - Wiley Online Library
It is well‐known that when the geometry and/or coefficients allow stable trapped rays, the
outgoing solution operator of the Helmholtz equation grows exponentially through a …

Perfectly-matched-layer truncation is exponentially accurate at high frequency

J Galkowski, D Lafontaine, E Spence - SIAM Journal on Mathematical Analysis, 2023 - SIAM
We consider a wide variety of Helmholtz scattering problems including scattering by
Dirichlet, Neumann, and penetrable obstacles. We consider a radial perfectly matched layer …

Local absorbing boundary conditions on fixed domains give order-one errors for high-frequency waves

J Galkowski, D Lafontaine… - IMA Journal of Numerical …, 2024 - academic.oup.com
We consider approximating the solution of the Helmholtz exterior Dirichlet problem for a
nontrapping obstacle, with boundary data coming from plane-wave incidence, by the …

Sharp Preasymptotic Error Bounds for the Helmholtz -FEM

J Galkowski, EA Spence - SIAM Journal on Numerical Analysis, 2025 - SIAM
In the analysis of the-version of the finite-element method (FEM), with fixed polynomial
degree, applied to the Helmholtz equation with wavenumber, the asymptotic regime is when …

Wavenumber-explicit stability and convergence analysis of hp finite element discretizations of Helmholtz problems in piecewise smooth media

M Bernkopf, T Chaumont-Frelet, JM Melenk - arXiv preprint arXiv …, 2022 - arxiv.org
We present a wavenumber-explicit convergence analysis of the hp finite element method
applied to a class of heterogeneous Helmholtz problems with piecewise analytic coefficients …

Does the Helmholtz boundary element method suffer from the pollution effect?

J Galkowski, EA Spence - Siam Review, 2023 - SIAM
In d dimensions, accurately approximating an arbitrary function oscillating with frequency
\lesssimk requires ∼ k^d degrees of freedom. A numerical method for solving the Helmholtz …

Domain decomposition preconditioners for high-order discretizations of the heterogeneous Helmholtz equation

S Gong, IG Graham, EA Spence - IMA Journal of Numerical …, 2021 - academic.oup.com
We consider one-level additive Schwarz domain decomposition preconditioners for the
Helmholtz equation with variable coefficients (modelling wave propagation in …

Decompositions of high-frequency Helmholtz solutions via functional calculus, and application to the finite element method

J Galkowski, D Lafontaine, EA Spence… - SIAM Journal on …, 2023 - SIAM
Over the last 10 years, results from [JM Melenk and S. Sauter, Math. Comp., 79 (2010), pp.
1871–1914],[JM Melenk and S. Sauter, SIAM J. Numer. Anal., 49 (2011), pp. 1210–1243],[S …

The -FEM applied to the Helmholtz equation with PML truncation does not suffer from the pollution effect

J Galkowski, D Lafontaine, EA Spence… - arXiv preprint arXiv …, 2022 - arxiv.org
We consider approximation of the variable-coefficient Helmholtz equation in the exterior of a
Dirichlet obstacle using perfectly-matched-layer (PML) truncation; it is well known that this …