Numerical boundary flux functions that give provable bounds for nonlinear initial boundary value problems with open boundaries

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Winters, Andrew R., Kopriva, David A., Nordström, Jan
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866918367069208576
author Winters, Andrew R.
Kopriva, David A.
Nordström, Jan
author_facet Winters, Andrew R.
Kopriva, David A.
Nordström, Jan
contents We present a strategy for interpreting nonlinear, characteristic-type penalty terms as numerical boundary flux functions that provide provable bounds for solutions to nonlinear hyperbolic initial boundary value problems with open boundaries. This approach is enabled by recent work that found how to express the entropy flux as a quadratic form defined by a symmetric boundary matrix. The matrix formulation provides additional information for how to systematically design characteristic-based penalty terms for the weak enforcement of boundary conditions. A special decomposition of the boundary matrix is required to define an appropriate set of characteristic-type variables. The new boundary fluxes are directly compatible with high-order accurate split form discontinuous Galerkin spectral element and similar methods and guarantee that the solution is entropy stable and bounded solely by external data. We derive inflow-outflow boundary fluxes specifically for the Burgers equation and the two-dimensional shallow water equations, which are also energy stable. Numerical experiments demonstrate that the new nonlinear fluxes do not fail in situations where standard boundary treatments based on linear analysis do.
format Preprint
id arxiv_https___arxiv_org_abs_2511_04197
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Numerical boundary flux functions that give provable bounds for nonlinear initial boundary value problems with open boundaries
Winters, Andrew R.
Kopriva, David A.
Nordström, Jan
Numerical Analysis
We present a strategy for interpreting nonlinear, characteristic-type penalty terms as numerical boundary flux functions that provide provable bounds for solutions to nonlinear hyperbolic initial boundary value problems with open boundaries. This approach is enabled by recent work that found how to express the entropy flux as a quadratic form defined by a symmetric boundary matrix. The matrix formulation provides additional information for how to systematically design characteristic-based penalty terms for the weak enforcement of boundary conditions. A special decomposition of the boundary matrix is required to define an appropriate set of characteristic-type variables. The new boundary fluxes are directly compatible with high-order accurate split form discontinuous Galerkin spectral element and similar methods and guarantee that the solution is entropy stable and bounded solely by external data. We derive inflow-outflow boundary fluxes specifically for the Burgers equation and the two-dimensional shallow water equations, which are also energy stable. Numerical experiments demonstrate that the new nonlinear fluxes do not fail in situations where standard boundary treatments based on linear analysis do.
title Numerical boundary flux functions that give provable bounds for nonlinear initial boundary value problems with open boundaries
topic Numerical Analysis
url https://arxiv.org/abs/2511.04197