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arXiv · 1702.06809

Toward a chaotic adjoint for LES

Patrick J. Blonigan·Pablo Fernandez·Scott M. Murman·Qiqi Wang·Georgios Rigas·Luca Magri
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Abstract

Adjoint-based sensitivity analysis methods are powerful tools for engineers who use flow simulations for design. However, the conventional adjoint method breaks down for scale-resolving simulations like large-eddy simulation (LES) or direct numerical simulation (DNS), which exhibit the chaotic dynamics inherent in turbulent flows. Sensitivity analysis based on least-squares shadowing (LSS) avoids the issues encountered by conventional methods, but has a high computational cost. The following report outlines a new, more computationally efficient formulation of LSS, non-intrusive LSS, and estimates its cost for several canonical flows using Lyapunov analysis.

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Patrick J. Blonigan, Pablo Fernandez, Scott M. Murman, Qiqi Wang, Georgios Rigas, Luca Magri. 2017-02-22. Toward a chaotic adjoint for LES. https://arxiv.org/abs/1702.06809

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