Development of Robust Boundary Layer Controllers

Abstract

In this study, control system analysis and design techniques were developed to control turbulent and convective boundary layers. The design was dependant solely on the linearized governing equations of a channel flow and a layer of heated fluid. The three-dimensional Navier-Stokes equations of channel flow, linearized about a Poisueille profile, and Oberbeck-Boussinesq equations of a layer of fluid, linearized about the no motion state, were decomposed by a spectral decomposition involving a two-dimensional Fourier expansion and a Chebyshev Calcrkin projection. The resulting temporal state space model, composed of the coefficients of this decomposition, allowed for a multivariable feedback design combining an array of sensors to an array of actuators. In particular, this spectral decomposition decouples the dynamical equations into a parallel architecture, where each wave number pair sub-system could he handled individually Linear Quadratic Guassian (LQC) multivariable synthesis and model reduction techniques are applied to a few select wave number pair sub-systems, reducing the required computational bandwidth. Controller performance was tested on direct numerical simulations. Even with a limited number of controlled wave number pairs and a drastic reduction in state space size, the controllers have proven remarkably effective.

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Document Details

Document Type
Technical Report
Publication Date
Nov 29, 2002
Accession Number
ADA416220

Entities

People

  • Jason L. Speyer
  • John J Kim

Organizations

  • University of California, Los Angeles

Tags

Communities of Interest

  • Air Platforms
  • Sensors
  • Space

DTIC Thesaurus Topics

  • Boundary Layer
  • Closed Loop Systems
  • Computational Fluid Dynamics
  • Computational Science
  • Control Systems
  • Differential Equations
  • Fluid Dynamics
  • Fluid Flow
  • Fluid Mechanics
  • Heat Transfer
  • Hypervelocity Flow
  • Mathematical Filters
  • Microelectromechanical Systems
  • Stratified Fluids
  • Three Dimensional
  • Turbulent Flow
  • Two Dimensional

Readers

  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Fluid Dynamics.
  • Robotics and Automation.

Technology Areas

  • Space
  • Space - Spacecraft Maneuvers