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arXiv · 1902.09061

An Artificial Compression Reduced Order Model

Victor DeCaria·Traian Iliescu·William Layton·Michael McLaughlin·Michael Schneier
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Abstract

We propose a novel artificial compression, reduced order model (AC-ROM) for the numerical simulation of viscous incompressible fluid flows. The new AC-ROM provides approximations not only for velocity, but also for pressure, which is needed to calculate forces on bodies in the flow and to connect the simulation parameters with pressure data. The new AC-ROM does not require that the velocity-pressure ROM spaces satisfy the inf-sup (Ladyzhenskaya-Babuska-Brezzi) condition and its basis functions are constructed from data that are not required to be weakly-divergence free. We prove error estimates for the reduced basis discretization of the AC-ROM. We also investigate numerically the new AC-ROM in the simulation of a two-dimensional flow between offset cylinders.

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Victor DeCaria, Traian Iliescu, William Layton, Michael McLaughlin, Michael Schneier. 2019-02-25. An Artificial Compression Reduced Order Model. https://arxiv.org/abs/1902.09061

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