On Delay-Based Linear Models and Robust Control of Cavity Flows

Abstract

Design and implementation of now control problems pose challenging difficulties as the now dynamics are governed by coupled nonlinear equations. Recent research outcomes stipulate that the problem can be studied either from a reduced order modeling point of view or from a transfer function point of view. The latter idcntifies the physics of the problem on the basis of separate components such as scattering, acoustics, shear layer etc. This chapter uses the transfer function representation and demonstrates a good match between the real-time observations and a well-tuned transfer function can be obtained. Utilizing the devised model, an H∞ controller based on Toker-Özbay formula is presented. The simulati on results illustrate that the effect of the noise can be eliminated significantly by appropriately exciting the now dynamics.