Coupling schemes for the FSI forward prediction challenge: Comparative study and validation

Self Cite

In order to reduce the complexity of heart hemodynamics simulations, uncoupling approaches are often considered for the modeling of the immersed valves as an alternative to complex fluid‐structure interaction (FSI) models. A possible shortcoming of these simplified approaches is the difficulty to correctly capture the pressure dynamics during the isovolumetric phases. In this work, we propose an enhanced resistive immersed surfaces (RIS) model of cardiac valves, which overcomes this issue. The benefits of the model are investigated and tested in blood flow simulations of the left heart where the physiological behavior of the intracavity pressure during the isovolumetric phases is recovered without using fully coupled fluid‐structure models and without important alteration of the associated velocity field.

scriptL

in Section ). The surface velocities are given by the following expressions for all x ∈ ∂ Ω 2,D :

w_{0} false(bold-italicx, t false) = bold-italic0 \forall t \in R^{+},

w_{iso} false(bold-italicx, t false) = ({, \begin{matrix} right 0 & left \forall t \in {double-struckR}^{+} | (R_{12} (t) \neq 0 and R_{23} (t) \neq 0), & right \\ right r (x, t) & left \forall t \in {double-struckR}^{+} | (R_{12} (t) = 0 or R_{23} (t) = 0,) \end{matrix})

…”

Section: Numerical Experimentsmentioning

confidence: 99%

“…The surface displacement prescribed on ∂ Ω 2,D is extended to the rest of the domain using an appropriate nonlinear lifting operator (denoted

scriptL

Section: Numerical Experimentsmentioning

confidence: 99%

Section: Toy Problemmentioning

confidence: 99%

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Augmented resistive immersed surfaces valve model for the simulation of cardiac hemodynamics with isovolumetric phases

This

Boilevin-Kayl

Fernández

et al. 2019

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“…50 At the same time, the coupling can be defined as loosely or strongly coupled. 51 In the former type of coupling, also called unidirectional, there is no feedback force to the structure. The strongly coupled technique, also called bidirectional or implicit is physically and numerically more accurate due to the enforced energy conservation.…”

Section: Coupled Multi-physics Cardiac Computational Modeling State Omentioning

confidence: 99%

“…Interaction with the fluid domain is imposed by one of two main methods: immersed boundary (IB) or arbitrary Lagrangian‐Eulerian (ALE) . At the same time, the coupling can be defined as loosely or strongly coupled . In the former type of coupling, also called unidirectional, there is no feedback force to the structure.…”

Section: Introductionmentioning

confidence: 99%

Fully coupled fluid‐electro‐mechanical model of the human heart for supercomputers

Santiago

Aguado-Sierra

Zavala-Aké

et al. 2018

In this work, we present a fully coupled fluid-electro-mechanical model of a 50th percentile human heart. The model is implemented on Alya, the BSC multi-physics parallel code, capable of running efficiently in supercomputers. Blood in the cardiac cavities is modeled by the incompressible Navier-Stokes equations and an arbitrary Lagrangian-Eulerian (ALE) scheme. Electrophysiology is modeled with a monodomain scheme and the O'Hara-Rudy cell model. Solid mechanics is modeled with a total Lagrangian formulation for discrete strains using the Holzapfel-Ogden cardiac tissue material model. The three problems are simultaneously and bidirectionally coupled through an electromechanical feedback and a fluid-structure interaction scheme. In this paper, we present the scheme in detail and propose it as a computational cardiac workbench.

Computational modeling of the fluid flow and the flexible intimal flap in type B aortic dissection via a monolithic arbitrary Lagrangian/Eulerian fluid‐structure interaction model

Ryzhakov

Soudah

Dialami

2019

In the present work, we perform numerical simulations of the fluid flow in type B aortic dissection (AD), accounting for the flexibility of the intimal flap. The interaction of the flow with the intimal flap is modeled using a monolithic arbitrary Lagrangian/Eulerian fluid‐structure interaction model. The model relies on choosing velocity as the kinematic variable in both domains (fluid and solid) facilitating the coupling. The fluid flow velocity and pressure evolution at different locations is studied and compared against the experimental evidence and the formerly published numerical simulation results. Several tear configurations are analyzed. Details of the fluid flow in the vicinity of the tears are highlighted. Influence of the tear size upon the fluid flow and the flap deformation is discussed.