Abstract
The control of a globally unstable boundary-layer flow along a two-dimensional cavity is considered. When perturbed by the worst-case initial condition, the flow exhibits a large transient growth associated with the development of a wave packet along the cavity shear layer followed by a global cycle related to the least stable global eigenmodes. The flow simulation procedure is coupled to a measurement feedback controller, which senses the wall shear stress at the downstream lip of the cavity and actuates at the upstream lip. A reduced model for the control optimization is obtained by a projection on the least stable global eigenmodes. The LQG controller is run in parallel to the Navier-Stokes time integration. It is shown that the controller is able to damp out the global oscillations.
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Åkervik, E., Hœpffner, J., Ehrenstein, U., Henningson, D.S. (2008). Model Reduction and Control of a Cavity-Driven Separated Boundary Layer. In: Morrison, J.F., Birch, D.M., Lavoie, P. (eds) IUTAM Symposium on Flow Control and MEMS. IUTAM Bookseries, vol 7. Springer, Dordrecht. https://doi.org/10.1007/978-1-4020-6858-4_17
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DOI: https://doi.org/10.1007/978-1-4020-6858-4_17
Publisher Name: Springer, Dordrecht
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