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Aeroelastic optimization of a helicopter rotor using an efficient sensitivity analysisTo reduce oscillatory hub loads in forward flight, a structural optimization analysis of a hingeless helicopter rotor has been developed and applied. The aeroelastic analysis of the rotor is based on a finite element method in space and time, and linked with automated optimization algorithms. For the optimization analysis two types of structural representation are used: a generic stiffness-distribution and a single-cell thin-walled beam. For the first type, the design variables are nonstructural mass and its placement, chordwise center of gravity offset from the elastic axis, and stiffness. For the second type, width, height and thickness of spar are used as design variables. For the behavior constraints, frequency placement, autorotational inertia and aeroelastic stability of the blade are included. The required sensitivity derivatives are obtained using a direct analytical approach. An optimum oscillatory hub load shows a 25-77 percent reduction for the generic blade, and 30-50 percent reduction for the box-beam.
Document ID
19900042182
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Lim, Joon W.
(Maryland Univ. College Park, MD, United States)
Chopra, Inderjit
(Maryland, University College Park, United States)
Date Acquired
August 14, 2013
Publication Date
January 1, 1990
Subject Category
Aircraft Design, Testing And Performance
Report/Patent Number
AIAA PAPER 90-0951
Meeting Information
Meeting: AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference
Location: Long Beach, CA
Country: United States
Start Date: April 2, 1990
End Date: April 4, 1990
Accession Number
90A29237
Funding Number(s)
CONTRACT_GRANT: NAG1-739
Distribution Limits
Public
Copyright
Other

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