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arXiv · 2111.04206

Finite element methods for large-strain poroelasticity/chemotaxis models simulating the formation of myocardial oedema

Nicolas Barnafi·Bryan Gómez-Vargas·Wesley de Jesus Lourenço·Ruy Freitas Reis·Bernardo Martins Rocha·Marcelo Lobosco·Ricardo Ruiz-Baier·Rodrigo Weber dos Santos
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Abstract

In this paper we propose a novel coupled poroelasticity-diffusion model for the formation of extracellular oedema and infectious myocarditis valid in large deformations, manifested as an interaction between interstitial flow and the immune-driven dynamics between leukocytes and pathogens. The governing partial differential equations are formulated in terms of skeleton displacement, fluid pressure, Lagrangian porosity, and the concentrations of pathogens and leukocytes. A five-field finite element scheme is proposed for the numerical approximation of the problem, and we provide the stability analysis for a simplified system emanating from linearisation. We also discuss the construction of an adequate, Schur complement based, nested preconditioner. The produced computational tests exemplify the properties of the new model and of the finite element schemes.

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Nicolas Barnafi, Bryan Gómez-Vargas, Wesley de Jesus Lourenço, Ruy Freitas Reis, Bernardo Martins Rocha, Marcelo Lobosco, Ricardo Ruiz-Baier, Rodrigo Weber dos Santos. 2021-11-07. Finite element methods for large-strain poroelasticity/chemotaxis models simulating the formation of myocardial oedema. https://doi.org/10.1007/s10915-022-01944-2

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