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Summary Numerical methods are proposed for the nonlinear Stokes‐Biot system modeling interaction of a free fluid with a poroelastic structure. We discuss time discretization and decoupling schemes that allow the fluid and the poroelastic structure computed independently using a common stress force along the interface. The coupled system of nonlinear Stokes and Biot is formulated as a least‐squares problem with constraints, where the objective functional measures violation of some interface conditions. The local constraints, the Stokes and Biot models, are discretized in time using second‐order schemes. Computational algorithms for the least‐squares problems are discussed and numerical results are provided to compare the accuracy and efficiency of the algorithms.
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This content will become publicly available on February 24, 2026
A Robin–Robin strongly coupled partitioned method for fluid–poroelastic structure interaction
Abstract This work focuses on the development of a novel, strongly-coupled, second-order partitioned method for fluid–poroelastic structure interaction. The flow is assumed to be viscous and incompressible, and the poroelastic material is described using the Biot model. To solve this problem, a numerical method is proposed, based on Robin interface conditions combined with the refactorization of the Cauchy’s one-legged ‘ϑ-like’ method. This approach allows the use of the mixed formulation for the Biot model. The proposed algorithm consists of solving a sequence of Backward Euler–Forward Euler steps. In the Backward Euler step, the fluid and poroelastic structure problems are solved iteratively until convergence. Then, the Forward Euler problems are solved using equivalent linear extrapolations. We prove that the iterative procedure in the Backward Euler step is convergent, and that the converged method is stable whenϑ∈ [1/2, 1]. Numerical examples are used to explore convergence rates with varying parameters used in our scheme, and to compare our method to a monolithic method based on Nitsche’s coupling approach.
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- PAR ID:
- 10594156
- Publisher / Repository:
- De Gruyter
- Date Published:
- Journal Name:
- Journal of Numerical Mathematics
- ISSN:
- 1570-2820
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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