Share Email Print

Proceedings Paper

Modeling damage in tapered flexbeams
Author(s): Ashish S. Purekar; Darryll J. Pines
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Flexbeams in hingeless rotors have non-uniform geometries to form virtual hinges for the lead-lag and flap motions of blades. For bearingless rotors, the flexbeams also contain a virtual hinge for the pitch of the blades. Commonly, flexbeams are damaged through high cyclic and vibratory loadings. Damage in the form of delamination for composite beams degrade performance and can potentially cause catastrophic failure. This paper develops an analytical model of tapered rotorcraft flexbeams. In a beam of uniform cross section, the transverse dynamics of a beam can be characterized by four wavetypes. By tracking the progression of the waves along the beam and back again, the wavetypes can be used to model the response. A more practical application of these wavetypes is to use them in a manner similar to shape functions for finite element analysis. The concept of a spectral element methodology is introduced for a uniform beam and then extended for an element with linearly varying width and thickness. A model of the delamination region is then incorporated into the spectral element methodology. Using this model for the dynamics of tapered beams, analytical results are then compared with experimental data for undamaged and damaged cases.

Paper Details

Date Published: 9 June 1999
PDF: 17 pages
Proc. SPIE 3668, Smart Structures and Materials 1999: Smart Structures and Integrated Systems, (9 June 1999); doi: 10.1117/12.350712
Show Author Affiliations
Ashish S. Purekar, Univ. of Maryland/College Park (United States)
Darryll J. Pines, Univ. of Maryland/College Park (United States)

Published in SPIE Proceedings Vol. 3668:
Smart Structures and Materials 1999: Smart Structures and Integrated Systems
Norman M. Wereley, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?