On the Coupling between a Supersonic Boundary Layer and a Flexible Surface

Abstract

The coupling between a two-dimensional, supersonic, laminar boundary layer and a flexible surface is studied using direct numerical computations of the Navier-Stokes equations coupled with the plate equation. The flexible surface is forced to vibrate by plane acoustic waves at normal incidence emanated by a sound source located on the side of the flexible surface opposite to the boundary layer. The effect of the source excitation frequency on the surface vibration and boundary layer stability is analyzed. The results show that, for frequencies near the fifth natural frequency of the surface or lower, large disturbances are introduced in the boundary layer that may alter its stability characteristics. The interaction between a stable two-dimensional disturbance of Tollmien-Schlichting (TS) type with the vibrating surface also is studied. The results show that the disturbance level is higher over the vibrating flexible surface than that obtained when the surface is rigid, which indicates a strong coupling between flow and structure. However, in the absence of the sound source the disturbance levels over the rigid and flexible surfaces are identical. This result is due to the high frequency of the TS disturbance, which does not couple with the flexible surface.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1992
Accession Number
ADA255833

Entities

People

  • Abdelkader Frendi
  • Alvin Bayliss
  • Lucio Maestrello

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Acoustic Waves
  • Boundary Layer
  • Differential Equations
  • Engineering
  • Equations
  • Flow
  • Flow Fields
  • Frequency
  • Laminar Boundary Layer
  • Mach Number
  • Navier Stokes Equations
  • Partial Differential Equations
  • Resonant Frequency
  • Steady State
  • Two Dimensional
  • Vibration
  • Waves

Fields of Study

  • Physics

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Fluid Mechanics and Fluid Dynamics.
  • Structural Dynamics.

Technology Areas

  • Hypersonics
  • Hypersonics - Hypersonic Boundary Layers
  • Hypersonics - Hypersonic Flight