Accession Number : ADA329660

Title :   Optimal and Robust Control Transition and Turbulence in Plane Channel Flow

Descriptive Note : Final technical rept. 1 Jan 93-30 Sep 96

Corporate Author : STANFORD UNIV CA DEPT OF MECHANICAL ENGINEERING

Personal Author(s) : Moin, Parviz ; Bewley, Thomas

PDF Url : ADA329660

Report Date : 19 DEC 1996

Pagination or Media Count : 68

Abstract : Efficient feedback control algorithms based on optimal and robust control theories have been formulated and tested in direct numerical simulations of turbulent channel flow. The optimization technique used is based solely on the equations governing the fluid flow and variations of a mathematical statement of the control objective, with out the heuristic procedures normally used to determine effective flow control algorithms. The control algorithms tested are shown to be extremely effective, and a host of new ideas for the determination of simple, implementable, effective control rules for turbulent flows have been proposed and are currently still under investigation. The problem of transition control via optimal and robust techniques has also been studied to draw parallels between the linear and nonlinear theories on problems of significant interest in fluid mechanics. Results on this problem have also been quite good and clearly demonstrate how the control theories are related. With this insight, an important extension of the concepts of robust control theory to nonlinear problems has been made.

Descriptors :   *FLUID MECHANICS, ALGORITHMS, TURBULENT FLOW, NONLINEAR SYSTEMS, TRANSITIONS, CONTROL THEORY, CHANNEL FLOW.

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE