A Preliminary Experimental Study of the Behavior of Disturbances Introduced into a Highly Accelerated Laminar Boundary Layer.

Abstract

An experimental study is described in which the effects of disturbances introduced into a highly accelerated, two-dimensional, laminar boundary layer were investigated. The disturbances were produced by a vibrating ribbon and the Reynolds number was in the range 400 - 1500. Small amplitude disturbances in the frequency range 10 - 150 Hz damped out quickly. For certain types of disturbances, apparent transition was observed even for values of the Reynolds number an order of magnitude below the minimum critical value given by classical theory. Tests were made to determine the nature of this transition, but no specific conclusion was developed on the basis of the available data. Comparison of measured and theoretical damping rates showed reasonable agreement for cases in which no transition occurred. The explanation of the observed effects, and the way in which the concepts of streamtube stretching under the influence of high acceleration is involved, requires further investigation. (Author)

Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1970
Accession Number
AD0714628

Entities

People

  • Coleman Dup. Donaldson
  • John E. Yates
  • Richard S. Snedeker

Tags

DTIC Thesaurus Topics

  • Agreements
  • Amplitude
  • Boundaries
  • Boundary Layer
  • Fluid Mechanics
  • Frequency
  • High Acceleration
  • Laminar Boundary Layer
  • Layers
  • Physical Properties
  • Reynolds Number
  • Transitions
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Control Systems Engineering.
  • Fluid Dynamics.
  • Mechanical Engineering/Mechanics of Materials.