The Effects of Acoustical Disturbances on Boundary Layer Transition.

Abstract

The analysis of transition from laminar to turbulent flow on a flat plate has been the subject of numerous investigations. In the present work, emphasis has been placed on establishing a computational technique which can be utilized to develop a basic understanding of the effects of the propagation of acoustic waves into a boundary layer, and the ultimate effect of such disturbances on transition. The nonlinear system of unsteady compressible partial differential equations have been solved by a MacCormack predictor-corrector scheme which allows the effect of imposed disturbances to be tracked in time. The question of the mismatch in propagation velocity between Tollmein Schlichting and acoustic waves has been studied. The program indicates that while disturbances are propagating with the speed of sound in the inviscid flow, the waves well within the boundary layer are propagating at a speed on the order of the freestream velocity and thus the boundary layer is being excited by the classical Tollmein Schlichting waves. The analysis thus indicates that the effect of acoustical disturbances on transition is similar to the effect of other perturbations as experiments have indicated. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Jan 25, 1978
Accession Number
ADA051497

Entities

People

  • Andrew Callegari
  • Gabriel Miller

Organizations

  • New York University

Tags

Communities of Interest

  • Air Platforms
  • Space
  • Weapons Technologies

DTIC Thesaurus Topics

  • Acoustic Waves
  • Aircrafts
  • Boundary Layer
  • Boundary Layer Transition
  • Computational Fluid Dynamics
  • Computational Science
  • Differential Equations
  • Equations
  • Equations Of Motion
  • Fluid Mechanics
  • Jet Propulsion
  • Mechanical Engineering
  • Mechanics
  • Military Research
  • Numerical Analysis
  • Partial Differential Equations
  • Physics Laboratories

Fields of Study

  • Physics

Readers

  • Acoustical Oceanography.
  • Fluid Dynamics.