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arXiv · 1711.09780

Streamline derivative projection-based POD-ROM for convection-dominated flows. Part I : Numerical Analysis

Mejdi Azaïez·Tomás Chacón Rebollo·Samuele Rubino
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Abstract

We introduce improved Reduced Order Models (ROM) for convection-dominated flows. These non-linear closure models are inspired from successful numerical stabilization techniques used in Large Eddy Simulations (LES), such as Local Projection Stabilization (LPS), applied to standard models created by Proper Orthogonal Decomposition (POD) of flows with Galerkin projection. The numerical analysis of the fully Navier-Stokes discretization for the proposed new POD-ROM is presented, by mainly deriving the corresponding error estimates. Also, we suggest an efficient practical implementation of the stabilization term, where the stabilization parameter is approximated by the Discrete Empirical Interpolation Method (DEIM).

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Mejdi Azaïez, Tomás Chacón Rebollo, Samuele Rubino. 2017-11-24. Streamline derivative projection-based POD-ROM for convection-dominated flows. Part I : Numerical Analysis. https://arxiv.org/abs/1711.09780

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