Direct Solution Techniques for Viscous Flow and Their Control

Abstract

Major objectives of this study of two- and three-dimensional low- speed viscous separated flow problems were to understand the effect of flow separation, unsteadiness, three-dimensionality and nonlinear dynamics in simple two- and three-dimensional flows and, subsequently, to examine the control of these flows. Significant effort was directed toward developing basic computational methods which were made available to interested researchers and organizations involved in computational fluid dynamics research. The several analyses developed include two-dimensional Navier-Stokes analyses for steady and unsteady bluff body separation and massively separated flow past generalized airfoils at high angle of attack; a passive flow-control analyses using a flap for a generalized airfoil; active flow control analyses using an oscillating flap modulated suction/injection and free-stream unsteadiness; nonlinear dynamical systems analysis for low-speed separated flows; and, finally, three- dimensional analysis using velocity and vorticity for internal flows. The finite-Re results obtained for steady bluff body separation revealed some anomalies in the existing theoretical models and should help in improving these models. The Navier-Stokes analysis for unsteady separation past a circular cylinder provided very accurate prediction of Reynolds stresses from the first principles. The generalized airfoil analysis provided an analytical grid- generation technique using Schwarz-Christoffel conformal mapping.

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1991
Accession Number
ADA236201

Entities

People

  • Kirti N. Ghia
  • Urmila Ghia

Organizations

  • University of Cincinnati

Tags

Communities of Interest

  • Energy and Power Technologies
  • Space

DTIC Thesaurus Topics

  • Boundary Layer
  • Computational Fluid Dynamics
  • Computational Science
  • Fluid Dynamics
  • Fluid Flow
  • Fluid Mechanics
  • Geometry
  • Hydrodynamics
  • Hypervelocity Flow
  • Mechanical Phenomena
  • Mechanical Properties
  • Mechanics
  • Physics Laboratories
  • Three Dimensional
  • Turbulent Mixing
  • Two Dimensional
  • Viscous Flow

Fields of Study

  • Physics

Readers

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