Separated Flows.

Abstract

This report contains a study of separation of three-dimensional steady flows and two-dimensional unsteady flows. During this reporting period, an analytical model of the laminar separation region in supersonic flow at high Reynolds number was formulated and shown to be in reasonable agreement with experimental results. The model gives scaling laws for the flow properties and length scales for the separation region. It was also shown that triple-deck theory is the valid limit for high Reynolds-number flows involving laminar separation and reattachment, on the basis of interacting boundary-layer theory. Another analysis demonstrated the nature of the flow near an abrupt change of surface height, such as steps and bases. Unsteady effects on three-dimensional boundary layers at large Reynolds number were analyzed and were found to fall into three distinct regimes of frequency parameter, based on triple-deck arguments. Algorithms were developed to treat separated flow problems, avoiding the difficulty of the separation singularity by use of time-marching in one case, and using a spectral method in the other case. Results have been obtained for both two and three-dimensional flows involving relatively large regions of separation.

Document Details

Document Type
Technical Report
Publication Date
Jan 29, 1986
Accession Number
ADA163551

Entities

People

  • Odus R. Burggraf

Organizations

  • Ohio State University

Tags

DTIC Thesaurus Topics

  • Boundaries
  • Boundary Layer
  • Flow
  • Fluid Dynamics
  • Fluid Flow
  • Layers
  • Reynolds Number
  • Scaling Laws
  • Steady Flow
  • Supersonic Flow
  • Three Dimensional
  • Three Dimensional Flow
  • Two Dimensional
  • Unsteady Flow

Fields of Study

  • Physics

Readers

  • Fluid Mechanics and Fluid Dynamics.
  • Theoretical Analysis.

Technology Areas

  • Hypersonics
  • Hypersonics - Hypersonic Boundary Layers