Investigation of Torsion Free Wing Trend Flutter Models.

Abstract

Four types of aluminum plate flutter models of a torsion free wing (TFW) were studied: (1) cantilever wing; (2) pitch restrained wing; (3) TFW with forward trim surface; and (4) TFW with aft trim surface. Models (3) and (4) included the effect of fuselage. Free vibration analyses were performed by using the finite element program NASTRAN. Generalized aerodynamic forces were computed by using the program LAT2D based on the subsonic lifting surface theory of Kussner. Flutter speeds and frequencies were predicted by using the program FLTTR based on the V-g method. The predicted flutter speeds were compared with available computed and tested results. The predicted flutter speeds for the four models were compared with each other and conclusions were made. To determine the designs that yielded higher flutter speeds, parametric studies were conducted by varying each of the six parameters: thickness parameter of the wing; thickness parameter of either trim surface; location of the wing pivot; length of the boom; swept angle of the wing; and swept angle of either trim surface. The effect of these parameters on the flutter speeds of models (3) and (4) were plotted as trend curves and discussions and conclusions were made. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Sep 15, 1978
Accession Number
ADA061942

Entities

People

  • C. H. Wan
  • Henry T. Y. Yang

Organizations

  • Purdue University

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Aerodynamic Forces
  • Aerospace Craft
  • Air Force
  • Air Force Facilities
  • Aircrafts
  • Airframes
  • Computer Programs
  • Frequency
  • Fuselages
  • Horizontal Stabilizers
  • Kernel Functions
  • Mechanics
  • Resonant Frequency
  • Surfaces
  • Vibration
  • Wind Tunnel Tests
  • Wind Tunnels

Fields of Study

  • Physics

Readers

  • Aerodynamics/Aeronautics.
  • Structural Dynamics.