Two-level substructuring and parallel mesh generation for domain decomposition methods

Yannis El Gharbi (1, 2) , Augustin Parret-Fréaud (2) , Christophe Bovet (3) , Pierre Gosselet (1, 4)

1 LMT - Laboratoire de mécanique et technologie
2 Safran Tech
3 DMAS, ONERA, Université Paris Saclay [Châtillon]
4 LaMcube - Laboratoire de Mécanique, Multiphysique, Multiéchelle - UMR 9013

This paper presents a new parallel mesh generation method leading to subdomains of shape well-suited to Schur based domain decomposition methods such as the FETI and BDD solvers. Starting from a coarse mesh, subdomains meshes are created in parallel through hierarchical mesh refinement and morphing techniques. The proposed methodology aims at limiting the occurrence of known pathological situations (jagged interfaces, misplaced heterogeneity with respect to the interfaces, …) that penalize the convergence of the solver. Furthermore, it enables to distribute and parallelize the mesh generation step in the early phases of the whole analysis. Besides its good behavior towards convergence, the mesh generation is thus distributed. The method is assessed, on several academical and industrial test cases, for both its parallel efficiency when creating the mesh and its capability to generate decomposition resulting in less FETI iterations.

Mots clés: FETI; Parallel mesh generation; Domain decomposition methods

Domaines: Mécanique [physics.med-ph]; Analyse numérique [math.NA]

Yannis El Gharbi, Augustin Parret-Fréaud, Christophe Bovet, Pierre Gosselet. Two-level substructuring and parallel mesh generation for domain decomposition methods. Finite Elements in Analysis and Design, 2021, 192, pp.103484. ⟨10.1016/j.finel.2020.103484⟩. ⟨hal-02881249v3⟩