Stochastic Non-Linear Flutter of Aeroelastic Structures.

Abstract

The linear and non-linear random modal interactions of a two degree-of-freedom aeroelastic structure are examined by using the Fokker-Planck equation approach. A general differential equation describing the evolution of the response moments is derived for any moment order. For the case of linear modal interaction this differential equation is found to constitute a closed set of moment equations. The stationary response is determined for various system parameters. It is found that the linear interaction results in a suppression of one mode when the uncoupled frequencies of the structure are close to each other. For the case of nonlinear modal (known as autoparametric) interaction the differential equation of the response moments forms an infinite coupled set of equations which are closed via two closure schemes. These are the Gaussian and non-Gaussian closure leads to 69 differential equations in the first four orders of response moments. The two sets are solved by numerical integration. Keywords: Equations of motion; Coefficients.

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Document Details

Document Type
Technical Report
Publication Date
Oct 21, 1985
Accession Number
ADA162748

Entities

People

  • Raouf A. Ibrahim

Organizations

  • Texas Tech University

Tags

Communities of Interest

  • Energy and Power Technologies
  • Human Systems
  • Space

DTIC Thesaurus Topics

  • Air Force
  • Classification
  • Coefficients
  • Differential Equations
  • Energy
  • Energy Transfer
  • Engineering
  • Equations
  • Equations Of Motion
  • Fokker Planck Equations
  • Frequency
  • Mechanical Engineering
  • Numerical Integration
  • Physical Properties
  • Resonant Frequency
  • Scientific Research
  • Stochastic Processes

Fields of Study

  • Mathematics

Readers

  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Statistical inference.
  • Structural Dynamics.