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arXiv · 1712.06523

POD for optimal control of the Cahn-Hilliard system using spatially adapted snapshots

Carmen Gräßle·Michael Hinze·Nicolas Scharmacher
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Abstract

The present work considers the optimal control of a convective Cahn-Hilliard system, where the control enters through the velocity in the transport term. We prove the existence of a solution to the considered optimal control problem. For an efficient numerical solution, the expensive high-dimensional PDE systems are replaced by reduced-order models utilizing proper orthogonal decomposition (POD-ROM). The POD modes are computed from snapshots which are solutions of the governing equations which are discretized utilizing adaptive finite elements. The numerical tests show that the use of POD-ROM combined with spatially adapted snapshots leads to large speedup factors compared with a high-fidelity finite element optimization.

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Carmen Gräßle, Michael Hinze, Nicolas Scharmacher. 2017-12-18. POD for optimal control of the Cahn-Hilliard system using spatially adapted snapshots. https://arxiv.org/abs/1712.06523

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