Nonlinear Dynamics and Control of Three-Dimensional Separated Flows

Abstract

Our objective in this project was to derive a mathematically exact theory of unsteady fluid flow separation. We have obtained analytic formulae for the location and shape of separation profiles in terms of measurable, wall-based physical quantities. These formulae can now be used to design feedback controllers that alter, destroy, or create separation. Our main achievements are as follows: (1) We have developed a mathematical theory of unsteady three-dimensional separation for flows with a steady mean component. (2) We have developed a theory of moving unsteady separation for flows with a time-varying mean component. (3) We have developed a theory of separation for two-dimensional flows with a slip boundary ((1)-(3) above cover no-slip boundaries) (4) We also conducted experiments to prove existence of a new three-dimensional separation pattern (separation along a limit cycle of the wall shear field) first predicted by our 3D steady separation theory.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Feb 28, 2009
Accession Number
ADA495394

Entities

People

  • George Haller

Organizations

  • Massachusetts Institute of Technology

Tags

Communities of Interest

  • Human Systems

DTIC Thesaurus Topics

  • Boundaries
  • Boundary Layer
  • Dynamics
  • Engineering
  • Equations
  • Flow
  • Flow Separation
  • Flow Visualization
  • Fluid Flow
  • Geometry
  • Mathematics
  • Mechanical Engineering
  • Nonlinear Dynamics
  • Three Dimensional
  • Two Dimensional
  • Two Dimensional Flow
  • Unsteady Flow

Fields of Study

  • Physics

Readers

  • Calculus or Mathematical Analysis
  • Fluid Mechanics and Fluid Dynamics.