The Helmholtz Dirichlet and Neumann problems on piecewise smooth open curves
Helsing, Johan LU
and Jiang, Shidong
(2025)
In Journal of Computational Physics
539.
- Abstract
A numerical scheme is presented for solving the Helmholtz equation with Dirichlet or Neumann boundary conditions on piecewise smooth open curves, where the curves may have corners and multiple junctions. Existing integral equation methods for smooth open curves rely on analyzing the exact singularities of the density at endpoints for associated integral operators, explicitly extracting these singularities from the densities in the formulation, and using global quadrature to discretize the boundary integral equation. Extending these methods to handle curves with corners and multiple junctions is challenging because the singularity analysis becomes much more complex, and constructing high-order quadrature for discretizing layer potentials... (More)
A numerical scheme is presented for solving the Helmholtz equation with Dirichlet or Neumann boundary conditions on piecewise smooth open curves, where the curves may have corners and multiple junctions. Existing integral equation methods for smooth open curves rely on analyzing the exact singularities of the density at endpoints for associated integral operators, explicitly extracting these singularities from the densities in the formulation, and using global quadrature to discretize the boundary integral equation. Extending these methods to handle curves with corners and multiple junctions is challenging because the singularity analysis becomes much more complex, and constructing high-order quadrature for discretizing layer potentials with singular and hypersingular kernels and singular densities is nontrivial. The proposed scheme is built upon the following two observations. First, the single-layer potential operator and the normal derivative of the double-layer potential operator serve as effective preconditioners for each other locally. Second, the recursively compressed inverse preconditioning (RCIP) method can be extended to address “implicit” second-kind integral equations. The scheme is high-order, adaptive, and capable of handling corners and multiple junctions without prior knowledge of the density singularity. It is also compatible with fast algorithms, such as the fast multipole method. The performance of the scheme is illustrated with several numerical examples.
(Less)
- author
- Helsing, Johan
LU
and Jiang, Shidong
- organization
- publishing date
- 2025-10
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Dirichlet problem, Helmholtz equation, Integral equation method, Neumann problem, Open surface problem, RCIP method
- in
- Journal of Computational Physics
- volume
- 539
- article number
- 114223
- publisher
- Academic Press
- external identifiers
-
- scopus:105010021383
- ISSN
- 0021-9991
- DOI
- 10.1016/j.jcp.2025.114223
- language
- English
- LU publication?
- yes
- id
- 2cf8adbe-234f-485a-92b3-9430548c3570
- date added to LUP
- 2025-11-04 11:07:55
- date last changed
- 2025-11-04 11:08:57
@article{2cf8adbe-234f-485a-92b3-9430548c3570,
abstract = {{<p>A numerical scheme is presented for solving the Helmholtz equation with Dirichlet or Neumann boundary conditions on piecewise smooth open curves, where the curves may have corners and multiple junctions. Existing integral equation methods for smooth open curves rely on analyzing the exact singularities of the density at endpoints for associated integral operators, explicitly extracting these singularities from the densities in the formulation, and using global quadrature to discretize the boundary integral equation. Extending these methods to handle curves with corners and multiple junctions is challenging because the singularity analysis becomes much more complex, and constructing high-order quadrature for discretizing layer potentials with singular and hypersingular kernels and singular densities is nontrivial. The proposed scheme is built upon the following two observations. First, the single-layer potential operator and the normal derivative of the double-layer potential operator serve as effective preconditioners for each other locally. Second, the recursively compressed inverse preconditioning (RCIP) method can be extended to address “implicit” second-kind integral equations. The scheme is high-order, adaptive, and capable of handling corners and multiple junctions without prior knowledge of the density singularity. It is also compatible with fast algorithms, such as the fast multipole method. The performance of the scheme is illustrated with several numerical examples.</p>}},
author = {{Helsing, Johan and Jiang, Shidong}},
issn = {{0021-9991}},
keywords = {{Dirichlet problem; Helmholtz equation; Integral equation method; Neumann problem; Open surface problem; RCIP method}},
language = {{eng}},
publisher = {{Academic Press}},
series = {{Journal of Computational Physics}},
title = {{The Helmholtz Dirichlet and Neumann problems on piecewise smooth open curves}},
url = {{http://dx.doi.org/10.1016/j.jcp.2025.114223}},
doi = {{10.1016/j.jcp.2025.114223}},
volume = {{539}},
year = {{2025}},
}