Theoretical and Computational Fluid Dynamics

, Volume 15, Issue 2, pp 65–81

Optimal Control of Nonmodal Disturbances in Boundary Layers

  • Peter Corbett
  • Alessandro Bottaro

DOI: 10.1007/s001620100043

Cite this article as:
Corbett, P. & Bottaro, A. Theoret Comput Fluid Dynamics (2001) 15: 65. doi:10.1007/s001620100043

Abstract.

The optimal control of infinitesimal flow disturbances experiencing the largest transient gain over a fixed time span, commonly termed “optimal perturbations,” is undertaken using a variational technique in two- and three-dimensional boundary layer flows. The cost function employed includes various energy metrics which can be weighted according to their perceived importance, simplifying the task of determining which terms are essential for a “good” control scheme. In the accelerated boundary layers investigated, disturbance kinetic energy can be typically reduced by about one order of magnitude. However, it seems impossible to suppress completely over the entire control interval; “good” control strategies still permit approximately an order magnitude growth over the initial energy at some point in the interval. It is shown that the control effort efficiently targets the physical mechanisms behind transient growth.

Copyright information

© Springer-Verlag Berlin Heidelberg 2001

Authors and Affiliations

  • Peter Corbett
    • 1
  • Alessandro Bottaro
    • 1
  1. 1.Institut de Mécanique des Fluides de Toulouse, Allée du Pr. Camille Soula, 31400 Toulouse, FranceFR