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arXiv · 1904.05577

Space-Time NURBS-Enhanced Finite Elements for Solving the Compressible Navier-Stokes Equations

Michel Make·Norbert Hosters·Marek Behr·Stefanie Elgeti
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Abstract

This article considers the NURBS-Enhanced Finite Element Method (NEFEM) applied to the compressible Navier-Stokes equations. NEFEM, in contrast to conventional finite element formulations, utilizes a NURBS-based computational domain representation. Such representations are typically available from Computer-Aided-Design tools. Within the NEFEM, the NURBS boundary definition is utilized only for elements that are touching the domain boundaries. The remaining interior of the domain is discretized using standard finite elements. Contrary to isogeometric analysis, no volume splines are necessary. The key technical features of NEFEM will be discussed in detail, followed by a set of numerical examples that are used to compare NEFEM against conventional finite element methods with the focus on compressible flow.

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Michel Make, Norbert Hosters, Marek Behr, Stefanie Elgeti. 2019-04-11. Space-Time NURBS-Enhanced Finite Elements for Solving the Compressible Navier-Stokes Equations. https://arxiv.org/abs/1904.05577

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