Codice | MOX 90 |
Titolo | A semi-implicit approach for fluid-structure interaction based on an algebraic fractional step method |
Data | 2006-10-23 |
Autore/i | Quaini, Annalisa; Quarteroni, Alfio |
Link | Download full text |
Abstract | We address the numerical simulation of fluid-structure interaction problems dealing with an incompressible fluid whose density is
close to the structure density. We propose a semi-implicit coupling scheme based on an algebraic fractional-step method. The
basic idea of a semi-implicit scheme consists in coupling implicitly the added-mass effect, while the other terms (dissipation, convection and geometrical non-linearities) are treated explicitly. Thanks to this kind of explicit-implicit splitting, computational costs can be reduced (in comparison to
fully implicit coupling algorithms) and the scheme remains stable for a wide range of discretization parameters. In this paper we propose to derive this kind of splitting from the algebraic
formulation of the coupled fluid-structure problem (after finite-element space discretization). This approach extends for the first time to fluid-structure problems the algebraic
fractional step methodology that was previously advocated to treat the pure fluid problem in a fixed domain. More particularly, for
the specific semi-implicit method presented in this report we adapt the Yosida scheme to the case of a coupled fluid-structure problem. This scheme relies on an approximate LU block factorization of the matrix obtained after the discretization in time and space of the fluid-structure
system.
We analyze the numerical performances of this scheme on 2D fluid-structure simulations performed with a simple 1D structure model. |
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