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arXiv · 1902.07113

Isogeometric analysis of linear free-surface potential flow

I. Akkerman·J. H. A. Meijer·M. ten Eikelder
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Abstract

This paper presents a novel variational formulation to simulate linear free-surface flow. The variational formulation is suitable for higher-order finite elements and higher-order and higher-continuity shape functions as employed in Isogeometric Analysis (IGA). The novel formulation combines the interior and free-surface problems in one monolithic formulation. This leads to exact energy conservation and superior performance in terms of accuracy when compared to a traditional segregated formulation. This is confirmed by the numerical computation of traveling waves in a periodic domain and a three-dimensional sloshing problem. The isogeometric approach shows significant improved performance compared to traditional finite elements. Even on very coarse quadratic NURBS meshes the dispersion error is virtually absent.

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I. Akkerman, J. H. A. Meijer, M. ten Eikelder. 2019-02-19. Isogeometric analysis of linear free-surface potential flow. https://doi.org/10.1016/j.oceaneng.2020.107114

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