Turbulent Spot Observations within a Hypervelocity Boundary Layer ona 5-degree Half-Angle Cone

Abstract

Laminar to turbulent transition is a critically important process in hypersonic vehicle design. Higher thermal loads, by half an order of magnitude or more, result from the increased heat transfer due to turbulent flow. Drag, skin friction, and other flow properties are also significantly impacted. Turbulent transition occurs through the genesis, growth, and propagation of isolated local turbulence patches, known as turbulent spots. H.W. Emmons (1951) was the first to propose that laminar boundary layers break down through the convergence of spots, after observations of a water-table analogy to air flow. Spot formation has been studied extensively in subsonic flows, notably by Narasimha (1957), Dhawan and Narasimha (1958), Chen and Thyson (1971), Abu-Ghannam and Shaw (1980), Narasimha (1985), and Simon (1995).

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Document Details

Document Type
Technical Report
Publication Date
Apr 01, 2012
Accession Number
ADA587721

Entities

People

  • Ivett Leyva
  • Joseph E. Shepherd
  • Joseph S. Jewell
  • Nicholaus J. Parziale

Organizations

  • Air Force Research Laboratory

Tags

Communities of Interest

  • Materials and Manufacturing Processes
  • Space
  • Weapons Technologies

DTIC Thesaurus Topics

  • Air Flow
  • Air Force Research Laboratories
  • Boundaries
  • Boundary Layer
  • Boundary Layer Transition
  • Computational Fluid Dynamics
  • Engineering
  • Flow
  • Fluid Dynamics
  • Fluid Flow
  • Fluid Mechanics
  • Heat Transfer
  • Hydrodynamics
  • Hypersonics
  • Layers
  • Turbulence
  • Turbulent Flow

Fields of Study

  • Physics

Readers

  • Fluid Mechanics and Fluid Dynamics.

Technology Areas

  • Hypersonics
  • Hypersonics - Hypersonic Boundary Layers