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arXiv · 1809.10896

High-Order Isogeometric Methods for Compressible Flows. I. Scalar Conservation Laws

Andrzej Jaeschke·Matthias Möller
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Abstract

Isogeometric analysis was applied very successfully to many problem classes like linear elasticity, heat transfer and incompressible flow problems but its application to compressible flows is very rare. However, its ability to accurately represent complex geometries used in industrial applications makes IGA a suitable tool for the analysis of compressible flow problems that require the accurate resolution of boundary layers. The convection-diffusion solver presented in this chapter, is an indispensable step on the way to developing a compressible flow solver for complex viscous industrial flows. It is well known that the standard Galerkin finite element method and its isogeometric counterpart suffer from spurious oscillatory behaviour in the presence of shocks and steep solution gradients. As a remedy, the algebraic flux correction paradigm is generalized to B-Spline basis functions to suppress the creation of oscillations and occurrence of non-physical values in the solution. This work provides early results for scalar conservation laws and lays the foundation for extending this approach to the compressible Euler equations.

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Andrzej Jaeschke, Matthias Möller. 2018-09-28. High-Order Isogeometric Methods for Compressible Flows. I. Scalar Conservation Laws. https://arxiv.org/abs/1809.10896

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