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arXiv · 1503.00884

Simultaneous Single-Step One-Shot Optimization with Unsteady PDEs

Stefanie Günther·Nicolas R. Gauger·Qiqi Wang
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Abstract

The single-step one-shot method has proven to be very efficient for PDE-constrained optimization where the partial differential equation (PDE) is solved by an iterative fixed point solver. In this approach, the simulation and optimization tasks are performed simultaneously in a single iteration. If the PDE is unsteady, finding an appropriate fixed point iteration is non-trivial. In this paper, we provide a framework that makes the single-step one-shot method applicable for unsteady PDEs that are solved by classical time-marching schemes. The One-shot method is applied to an optimal control problem with unsteady incompressible Navier-Stokes equations that are solved by an industry standard simulation code. With the Van-der-Pol oscillator as a generic model problem, the modified simulation scheme is further improved using adaptive time scales. Finally, numerical results for the advection-diffusion equation are presented.

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Stefanie Günther, Nicolas R. Gauger, Qiqi Wang. 2015-03-03. Simultaneous Single-Step One-Shot Optimization with Unsteady PDEs. https://arxiv.org/abs/1503.00884

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