Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published January 2007 | Published
Conference Paper Open

Low-Dimensional Models for Control of Leading-Edge Vortices: Equilibria and Linearized Models


When an airfoil is pitched up rapidly, a dynamic stall vortex forms at the leading edge and produces high transient lift before shedding and stall occur. The aim of this work is to develop low-dimensional models of the dynamics of these leading-edge vortices, which may be used to develop feedback laws to stabilize these vortices using closed-loop control, and maintain high lift. We first perform a numerical study of the two-dimensional incompressible flow past an airfoil at varying angles of attack, finding steady states using a timestepper-based Newton/GMRES scheme, and dominant eigenvectors using ARPACK. These steady states may be either stable or unstable; we develop models linearized about the stable steady states using a method called Balanced Proper Orthogonal Decomposition, an approximation of balanced truncation that is tractable for large systems. The balanced POD models dramatically outperform models using the standard POD/Galerkin procedure, and are used to develop observers that reconstruct the flow state from a single surface pressure measurement.

Additional Information

© 2007 by the authors. Published by the American Institute of Aeronautics and Astronautics, Inc. with permission. Published Online: 18 Jun 2012. We gratefully acknowledge Sam Taira for help with the immersed boundary simulations, and Liang Qiao for help with timestepper based analysis of steady states. This research was supported by AFOSR, grants FA9550-05-1-0369 and FA9550-06-1-0371.

Attached Files

Published - AhujaRowleyKevrekidisEtAl2007.pdf


Files (1.2 MB)
Name Size Download all
1.2 MB Preview Download

Additional details

August 19, 2023
October 20, 2023