Application of Trigonometric and Conventional Finite Difference Approximations to Beam Buckling.

Abstract

A relatively new trigonometric approach to the finite difference calculus was applied to the problem of beam buckling as represented by both virtual work and equilibrium equations. The trigonometric functions were varied by adjusting a wave-length parameter in the approximating Fourier series. Values of the critical force obtained from the modified approach for beams with a variety of boundary conditions were compared to results using the conventional finite difference method. The trigonometric approach produced significantly more accurate approximations for the critical force than the conventional approach for a relatively wide range in values of the wavelength parameter; and the optimizing value of the wavelength parameter corresponded to the half wavelength of the buckled mode shape. It was found from a modal analysis that the most accurate solutions are obtained when the approximating function closely represents the actual displacement function.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1977
Accession Number
ADA048371

Entities

People

  • Steven Ray Hannah

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Energy and Power Technologies
  • Weapons Technologies

DTIC Thesaurus Topics

  • Accuracy
  • Air Force
  • Algorithms
  • Buckling
  • Calculus
  • Computers
  • Differential Equations
  • Displacement
  • Eigenvalues
  • Eigenvectors
  • Engineering
  • Engineers
  • Equations
  • Fourier Series
  • Mechanics
  • Modal Analysis
  • Structural Mechanics

Readers

  • Approximation Theory.
  • Structural Dynamics.