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Aeroelastic behavior of composite rotor blades with swept tipsThis paper presents an analytical study of the aeroelastic behavior of composite rotor blades with straight and swept tips. The blade is modeled by beam type finite elements. A single finite element is used to model the swept tip. The nonlinear equations of motion for the finite element model are derived using Hamilton's principle and based on a moderate deflection theory and accounts for: arbitrary cross-sectional shape, pretwist, generally anisotropic material behavior, transverse shears and out-of-plane warping. Numerical results illustrating the effects of tip sweep, anhedral and composite ply orientation on blade aeroelastic behavior are presented. It is shown that composite ply orientation has a substantial effect on blade stability. At low thrust conditions, certain ply orientations can cause instability in the lag mode. The flap-torsion coupling associated with tip sweep can also induce aeroelastic instability in the blade. This instability can be removed by appropriate ply orientation in the composite construction.
Document ID
19930051981
Document Type
Conference Paper
Authors
Yuan, Kuo-An (NASA Langley Research Center Hampton, VA, United States)
Friedmann, Peretz P. (NASA Langley Research Center Hampton, VA, United States)
Venkatesan, Comandur (California Univ. Los Angeles, United States)
Date Acquired
August 16, 2013
Publication Date
January 1, 1992
Publication Information
Publication: In: AHS, Annual Forum, 48th, Washington, June 3-5, 1992, Proceedings. Vol. 2 (A93-35901 14-01)
Subject Category
STRUCTURAL MECHANICS
Funding Number(s)
CONTRACT_GRANT: NAG1-833
Distribution Limits
Public
Copyright
Other