Calculated and Measured Blade Structural Response on a Full-Scale Rotor

Abstract

The restricted problem of calculating the bending-moment response of a full-scale rotor to measured airloads is studied. Data are used from separate tests of an articulated rotor in flight and in a wind tunnel. Linear equations to represent the blade mass and structure are used, and the solution is obtained by numerically solving the resulting two-point boundary problem. The measured aerodynamic loads include effects caused by both rigid blade motion and elastic deformation and hence, represent an exact aerodynamic model. By comparing the calculated blade-bending and torsional-moment response with measurement, it is possible to assess the adequacy of the structural model for the calculation of calculating vibratory loads. These comparisons are good for the flap- and torsional-moments at the lower harmonics. Calculations for the chord-bending moments are less satisfactory and reveal problems with the method of deriving the chord airloads from the measured normal forces, or the representation of the nonlinear lead-lag damper.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1986
Accession Number
ADA174261

Entities

People

  • Jacques Esculier
  • William G. Bousman

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Aircrafts
  • Bending Moments
  • Blade Tips
  • Control Systems
  • Differential Equations
  • Equations
  • Equations Of Motion
  • Frequency
  • Grids
  • Helicopters
  • Measurement
  • Partial Differential Equations
  • Strain Gages
  • Transducers
  • Trim Angle
  • Wind Tunnel Tests
  • Wind Tunnels

Fields of Study

  • Physics

Readers

  • Aerodynamics.
  • Calculus or Mathematical Analysis
  • Structural Dynamics.