School of Engineering and Materials Science
Research Student Awards
PhD Thesis: Closed-loop flow control for bundary layer instabilities
Author: ZHANG, Zhenyu
Supervisor(s): Mike Gaster
The study in this thesis attempts to find an efficient closed-loop active control scheme to cancel the unstable Tollmien-Schlichting waves in a transitional boundary layer flow. The T-S instabilities was simulated by numerical solutions of the linearised Navier-Stokes equation system. Controllers were designed according to the frequency characteristics of the disturbed flowfield and implemented on the basis of the classical control theory in frequency domain. The performance of controllers in the disturbed boundary layer flow along a flat plate were evaluated through numerical simulations and then validated by experiments.