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

Jeffrey Galkowski, David Lafontaine, Euan A. Spence

Research output: Contribution to journalArticlepeer-review

3 Downloads (Pure)

Abstract

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 solution of the corresponding boundary value problem where the exterior domain is truncated and a local absorbing boundary condition coming from a Pad\'e approximation (of arbitrary order) of the Dirichlet-to-Neumann map is imposed on the artificial boundary (recall that the simplest such boundary condition is the impedance boundary condition). We prove upper- and lower-bounds on the relative error incurred by this approximation, both in the whole domain and in a fixed neighbourhood of the obstacle (i.e. away from the artificial boundary). Our bounds are valid for arbitrarily-high frequency, with the artificial boundary fixed, and show that the relative error is bounded away from zero, independent of the frequency, and regardless of the geometry of the artificial boundary.
Original languageEnglish
Article numberdrad058
Number of pages124
JournalIMA Journal of Numerical Analysis
DOIs
Publication statusPublished - 9 Sept 2023

Keywords

  • math.NA
  • cs.NA
  • math.AP
  • 35J05, 65N99

Fingerprint

Dive into the research topics of 'Local absorbing boundary conditions on fixed domains give order-one errors for high-frequency waves'. Together they form a unique fingerprint.

Cite this