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arXiv · 2308.06494

Immersed-Boundary Fluid-Structure Interaction of Membranes and Shells

Marin Lauber·Gabriel D. Weymouth·Georges Limbert
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Abstract

This paper presents a general and robust method for the fluid-structure interaction of membranes and shells undergoing large displacement and large added-mass effects by coupling an immersed-boundary method with a shell finite-element model. The immersed boundary method can accurately simulate the fluid velocity and pressure induced by dynamic bodies undergoing large displacements using a computationally efficient pressure projection finite volume solver. The structural solver can be applied to bending and membrane-related problems, making our partitioned solver very general. We use a strongly-coupled algorithm that avoids the expensive computation of the inverse Jacobian within the root-finding iterations by constructing it from input-output pairs of the coupling variables from the previous time steps. Using two examples with large deformations and added mass contributions, we demonstrate that the resulting quasi-Newton scheme is stable, accurate, and computationally efficient.

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Marin Lauber, Gabriel D. Weymouth, Georges Limbert. 2023-08-12. Immersed-Boundary Fluid-Structure Interaction of Membranes and Shells. https://arxiv.org/abs/2308.06494

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