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arXiv · 1205.6887

Stability of the kinematically coupled \beta-scheme for fluid-structure interaction problems in hemodynamics

Suncica Canic·Boris Muha·Martina Bukac
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Abstract

It is well-known that classical Dirichlet-Neumann loosely coupled partitioned schemes for fluid-structure interaction (FSI) problems are unconditionally unstable for certain combinations of physical and geometric parameters that are relevant in hemodynamics. It was shown in \cite{causin2005added} on a simple test problem, that these instabilities are associated with the so called ``added-mass effect''. By considering the same test problem as in \cite{causin2005added}, the present work shows that a novel, partitioned, loosely coupled scheme, recently introduced in \cite{MarSun}, called the kinematically coupled $\beta$-scheme, does not suffer from the added mass effect for any $\beta \in [0,1]$, and is unconditionally stable for all the parameters in the problem. Numerical results showing unconditional stability are presented for a full, nonlinearly coupled benchmark FSI problem, first considered in \cite{formaggia2001coupling}.

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Suncica Canic, Boris Muha, Martina Bukac. 2012-05-31. Stability of the kinematically coupled \beta-scheme for fluid-structure interaction problems in hemodynamics. https://arxiv.org/abs/1205.6887

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