Investigation of an Improved Structural Model for Damaged T-38 Horizontal Stabilizer Flutter Analysis Using NASTRAN.

Abstract

This thesis investigates tuning a finite element model and applying the procedures to the T-38 horizontal stabilizer for use on NASTRAN. The T-38 stabilizer model is to be used in a subsequent flutter analysis. Static and dynamic analysis has shown the model to have inadequate bending and torsional stiffness. The model was tuned in the frequency domain with free-free boundary conditions. the tuned frequencies and mode shapes show good correlation to the measured values. The finite element model was shown to not contain variables that significantly influence the torsion modes frequencies more than the bending frequencies. Eigenvalue analysis of the tuned model with aircraft installed boundary conditions produced good results for all but the frist torsion frequency. This frequency was tuned by increasing the model's control system stiffness. This tuned model produces good frequencies and mode shapes. Additional investigation is needed to compare the dynamic model corrections to the static model corrections found by Jack Sawdy, AF IT/GAE/AA/81D-27. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1981
Accession Number
ADA111095

Entities

People

  • Lex Clayton Dodge

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Air Force
  • Aircrafts
  • Airfoils
  • Boundaries
  • Classification
  • Control Systems
  • Eigenvalues
  • Frequency
  • Horizontal Stabilizers
  • Modulus Of Elasticity
  • Numerical Analysis
  • Shear Modulus
  • Stiffness
  • Surfaces
  • Three Dimensional
  • Transient Response Analysis
  • Two Dimensional

Readers

  • Computational Modeling and Simulation
  • Structural Dynamics.