Bound-preserving finite element approximations of the Keller-Segel equations

This paper aims to develop numerical approximations of the Keller{Segel equations that mimic at the discrete level the lower bounds and the energy law of the continuous problem. We solve these equations for two unknowns: the organism (or cell) density, which is a positive variable, and the chemoattr...

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Detalles Bibliográficos
Autores: Badia, Santiago, Bonilla, Jesús, Gutiérrez Santacreu, Juan Vicente
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2023
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/168309
Acceso en línea:https://hdl.handle.net/11441/168309
https://doi.org/10.1142/S0218202523500148
Access Level:acceso abierto
Palabra clave:Keller-Segel equations
Nonlinear parabolic equations
Shock detector
Lower bounds
Energy law
Descripción
Sumario:This paper aims to develop numerical approximations of the Keller{Segel equations that mimic at the discrete level the lower bounds and the energy law of the continuous problem. We solve these equations for two unknowns: the organism (or cell) density, which is a positive variable, and the chemoattractant density, which is a non-negative variable. We propose two algorithms, which combine a stabilized nite element method and a semi-implicit time integration. The stabilization consists of a nonlinear arti cial di usion that employs a graph-Laplacian operator and a shock detector that localizes local extrema. As a result, both algorithms turn out to be nonlinear and can generate cell and chemoattractant numerical densities ful lling lower bounds. However, the rst algorithm requires a suitable constraint between the space and time discrete parameters, whereas the second one does not. We design the latter to attain a discrete energy law on acute meshes.