# Second-order adjoint-based sensitivity for hydrodynamic stability and control

@article{Boujo2021SecondorderAS, title={Second-order adjoint-based sensitivity for hydrodynamic stability and control}, author={Edouard Boujo}, journal={Journal of Fluid Mechanics}, year={2021}, volume={920} }

Abstract Adjoint-based sensitivity analysis is routinely used today to assess efficiently the effect of open-loop control on the linear stability properties of unstable flows. Sensitivity maps identify regions where small-amplitude control is the most effective, i.e. yields the largest first-order (linear) eigenvalue variation. In this study an adjoint method is proposed for computing a second-order (quadratic) sensitivity operator, and applied to the flow past a circular cylinder, controlled…

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