Aeroelastic Response Analysis of Two Dimensional, Single and Two Degree of Freedom Airfoils in Low-Frequency, Small-Disturbance Unsteady Transonic Flow

Abstract

A procedure is developed to obtain the aeroelastic responses of single and two degree of freedom aeroelastic systems in transonic flow. The fluid is described by the two dimensional unsteady low-frequency transonic potential equation based on small disturbance theory. The aerodynamic computer code LTRAN2 which is based on a fully implicit time integration scheme is employed to obtain the aerodynamic forces. The structural equations are simultaneously integrated with the potential flow equations by a numerical method and the aeroelastic responses are obtained. Results for neutrally stable responses are compared with those obtained by the U-g method. Aeroelastic responses are obtained for flat plates (single and two degree of freedom) at M = 0.7 by the linear part of LTRAN2. Examples of an NACA 64A006 airfoil at Mach numbers of 0.88 and 0.85 are also analyzed. Response results obtained for a single pitching degree of freedom system at M = 0.88 are compared with an existing solution. The response results obtained for a two degree of freedom system at M = 0.85 for neutrally stable condition are correlated with those obtained by the flutter analysis. Results also include stable and unstable response curves and their variations with altitude.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1979
Accession Number
ADA073379

Entities

People

  • A. G. Striz
  • P. Guruswamy
  • T. Y. Yang

Organizations

  • Purdue University

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Aerodynamic Forces
  • Air Force
  • Air Masses
  • Aircrafts
  • Differential Equations
  • Equations
  • Equations Of Motion
  • Free Stream
  • Grids
  • Kernel Functions
  • Mach Number
  • Moment Of Inertia
  • Pressure Distribution
  • Shock Waves
  • Steady State
  • Trailing Edges
  • Transonic Flow

Fields of Study

  • Physics

Readers

  • Aerodynamics.
  • Aerodynamics/Aeronautics.
  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.