Iterative control of Görtler vortices via local wall deformations

Sescu, Adrian and Taoudi, Lamaie and Afsar, Mohammed (2017) Iterative control of Görtler vortices via local wall deformations. Theoretical and Computational Fluid Dynamics. pp. 1-10. ISSN 1432-2250

[img]
Preview
Text (Sescu-etal-TCFD2017-Iterative-control-of-Gortler-vortices-via-local-wall-deformations)
Sescu_etal_TCFD2017_Iterative_control_of_Gortler_vortices_via_local_wall_deformations.pdf
Accepted Author Manuscript

Download (668kB)| Preview

    Abstract

    Görtler vortices develop along concave walls as a result of the imbalance between the centrifugal force and radial pressure gradient. In this study, we introduce a simple control strategy aimed at reducing the growth rate of Görtler vortices by locally modifying the surface geometry in span- wise and streamwise directions. Such wall deformations are accounted in the boundary region equations (BRE) by using a Prandtl transform of dependent and independent variables. The vortex energy is then controlled via a classical proportional control algorithm for which either the wall-normal velocity or the wall shear stress serves as the control variable. Our numerical results indicate that the control algorithm is quite effective in minimizing the wall shear stress.