Aeroelastic Flutter and Divergence of Graphite/Epoxy Cantilevered Plates with Bending-Torsion Stiffness Coupling.

Abstract

The aeroelastic flutter and divergence behavior of rectangular, graphite/epoxy, cantilevered plates with varying amounts of bending-torsion stiffness coupling is investigated for incompressible flow. A general Rayleigh-Ritz formulation is used to calculate flexibility influence coefficients, static deflections, divergence velocities, vibration frequencies, and flutter velocities. Flutter calculations are done using the U-g method. Test plates were constructed and subjected to static, vibration and wind tunnel tests. Wind tunnel tests indicated static deflections, divergence instabilities, bending-torsion flutter at low angles of attack, and stall flutter at high angles of attack. Bending stiffness and first bending frequencies showed good agreement between theory and experiment. Torsional stiffness and first torsion frequencies were not accurately predicted by the theory for highly coupled plates. Divergence velocities and reduced flutter velocities showed reasonable agreement between theory and experiment. Test plates with varying amounts of coupling exhibited markedly different stall flutter characteristics. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1981
Accession Number
ADA101726

Entities

People

  • Steven James Hollowell

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Aerodynamic Forces
  • Aeronautics
  • Air Force
  • Aircrafts
  • Barometric Pressure
  • Calibration
  • Composite Materials
  • Data Reduction
  • Engineering
  • Materials Laboratories
  • Materials Processing
  • Materials Testing
  • Measurement
  • Resonant Frequency
  • Swept Wings
  • Two Dimensional
  • Wind Tunnel Tests

Fields of Study

  • Physics

Readers

  • Aerodynamics/Aeronautics.
  • Structural Dynamics.