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arXiv · 2308.07742

Optimization of piecewise smooth shapes under uncertainty using the example of Navier-Stokes flow

Caroline Geiersbach·Tim Suchan·Kathrin Welker
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Abstract

We investigate a complex system involving multiple shapes to be optimized in a domain, taking into account geometric constraints on the shapes and uncertainty appearing in the physics. We connect the differential geometry of product shape manifolds with multi-shape calculus, which provides a novel framework for the handling of piecewise smooth shapes. This multi-shape calculus is applied to a shape optimization problem where shapes serve as obstacles in a system governed by steady state incompressible Navier-Stokes flow. Numerical experiments use our recently developed stochastic augmented Lagrangian method and we investigate the choice of algorithmic parameters using the example of this application.

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Caroline Geiersbach, Tim Suchan, Kathrin Welker. 2023-08-15. Optimization of piecewise smooth shapes under uncertainty using the example of Navier-Stokes flow. https://arxiv.org/abs/2308.07742

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