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arXiv · 1811.09704

A projection-based numerical integration scheme for embedded interface: Application to fluid-structure interaction

Bin Liu·Rajeev Kumar Jaiman·Danielle Sweimann Tan
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Abstract

We present a projection-based numerical integration technique to deal with embedded interface in finite element (FE) framework. The element cut by an embedded interface is denoted as a cut cell. We recognize elemental matrices of a cut cell can be reconstructed from the elemental matrices of its sub-divided cells, via projection at matrix level. These sub-divided cells are termed as integration cells. The proposed technique possesses following characteristics (1) no change in FE formulation and quadrature rule; (2) consistency with the derivation of FE formulation in variational principle. It can be considered as a re-projection of the residuals of equation system in the test function space or a reduced-order modeling (ROM) technique. These characteristics significantly improves its scalability, easy-to-implementation and robustness to deal with problems involving embedded discontinuities in FE framework. Numerical examples, e.g., vortex-induced vibration (VIV), rotation, free fall and rigid-body contact in which the proposed technique is implemented to integrate the variational form of Navier-Stokes equations in cut cells, are presented.

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Bin Liu, Rajeev Kumar Jaiman, Danielle Sweimann Tan. 2018-11-18. A projection-based numerical integration scheme for embedded interface: Application to fluid-structure interaction. https://doi.org/10.1016/j.jcp.2020.109461

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