Control of Structural Vibrations by Vorticity Production.

Abstract

Analytical models are investigated of the damping of sound and structural vibrations by vorticity production in the apertures of bias flow and grazing flow perforated elastic plates. A generalized bending wave equation is formulated for a plate perforated with an homogeneous distribution of small apertures, and is used to predict the attenuation of sound and resonant bending waves. The results depend on the Rayleigh conductivity of an aperture in a thin plate which is determined numerically in the presence of one and two-sided mean grazing flows. The Kutta condition is applied to model the generation of vorticity at the edges of the aperture by an applied time-varying pressure field. The influence of flow nonlinearity in the apertures is investigated by use of a model equation for the aperture flows. Preliminary validation tests are described, and recommendations made for future research.

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Document Details

Document Type
Technical Report
Publication Date
Feb 01, 1996
Accession Number
ADA309976

Entities

People

  • Michael S. Howe

Organizations

  • Boston University

Tags

Communities of Interest

  • Energy and Power Technologies
  • Sensors

DTIC Thesaurus Topics

  • Acoustic Propagation
  • Acoustic Waves
  • Acoustics
  • Applied Mathematics
  • Boundary Layer
  • Computational Fluid Dynamics
  • Computational Science
  • Convection
  • Energy Transfer
  • Equations
  • Fluid Dynamics
  • Fluid Mechanics
  • Hydrodynamics
  • Mechanics
  • Turbulent Mixing
  • Wave Equations
  • Wave Power

Fields of Study

  • Physics

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Fluid Dynamics.
  • Structural Health Monitoring of Composite Structures.