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arXiv · 2101.05090

A novel approach to fluid-structure interaction simulations involving large translation and contact

Daniel Hilger·Norbert Hosters·Fabian Key·Stefanie Elgeti·Marek Behr
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Abstract

In this work, we present a novel method for the mesh update in flow problems with moving boundaries, the phantom domain deformation mesh update method (PD-DMUM). The PD-DMUM is designed to avoid remeshing; even in the event of large, unidirectional displacements of boundaries. The method combines the concept of two mesh adaptation approaches: (1) The virtual ring shear-slip mesh updatemethod (VR-SSMUM); and (2) the elastic mesh update method (EMUM). As in the VR-SSMUM, the PD-DMUMextends the fluid domain by a phantom domain; the PD-DMUM can thus locally adapt the element density. Combined with the EMUM, the PD-DMUMallows the consideration of arbitrary boundary movements. In this work, we apply the PD-DMUM in two test cases. Within the first test case, we validate the PD-DMUM in a 2D Poiseuille flow on a moving background mesh. Subsequently the fluid-structure interaction (FSI) problem in the second test case serves as a proof of concept. More, we stress the advantages of the novel method with regard to conventional mesh update approaches.

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Daniel Hilger, Norbert Hosters, Fabian Key, Stefanie Elgeti, Marek Behr. 2021-01-13. A novel approach to fluid-structure interaction simulations involving large translation and contact. https://arxiv.org/abs/2101.05090

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