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arXiv · 2012.10073

Recycling augmented Lagrangian preconditioner in an incompressible fluid solver

Maxim Olshanskii·Alexander Zhiliakov
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Abstract

The paper discusses a reuse of matrix factorization as a building block in the Augmented Lagrangian (AL) and modified AL preconditioners for non-symmetric saddle point linear algebraic systems. The strategy is applied to solve two-dimensional incompressible fluid problems with efficiency rates independent of the Reynolds number. The solver is then tested to simulate motion of a surface fluid, an example of a 2D flow motivated by an interest in lateral fluidity of inextensible viscous membranes. Numerical examples include the Kelvin--Helmholtz instability problem posed on the sphere and on the torus. Some new eigenvalue estimates for the AL preconditioner are derived.

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Maxim Olshanskii, Alexander Zhiliakov. 2020-12-18. Recycling augmented Lagrangian preconditioner in an incompressible fluid solver. https://doi.org/10.1002/nla.2415

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