Nonlinear Equations for Dynamics of Pretwisted Beams Undergoing Small Strains and Large Rotations.

Abstract

Nonlinear beam kinematics are developed and applied to the dynamic analysis of a pretwisted, rotating beam element. The common practice of assuming moderate rotations caused by structural deformation in geometric nonlinear analyses of rotating beams has been abandoned in the present analysis. The kinematic relations that describe the orientation of the cross section during deformation are simplified by systematically ignoring the extensional strain compared to unity in those relations. Open cross section effects such as warping rigidity and dynamics are ignored, but other influences of warp are retained. THe beam cross section is not allowed to deform in its own plane. Various means of implementation are discussed, including a finite element formulation. Numerical results obtained for nonlinear static problems show remarkable agreement with experiment. Keywords: Dynamic structural analysis; Rotating beams; Helicopter rotors. (Author)

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1985
Accession Number
ADA156934

Entities

People

  • D. H. Hodges

Organizations

  • Ames Research Center

Tags

Communities of Interest

  • Air Platforms
  • C4I
  • Space

DTIC Thesaurus Topics

  • Angular Acceleration
  • Boundaries
  • Computational Science
  • Constitutive Equations
  • Coordinate Systems
  • Curvature
  • Differential Equations
  • Elongation
  • Equations
  • Equations Of Motion
  • Experimental Data
  • Helicopter Rotors
  • Kinematics
  • Mechanics
  • Partial Differential Equations
  • Shape
  • Transient Response Analysis

Fields of Study

  • Physics

Readers

  • Structural Dynamics.