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Aeroelastic stability and response of horizontal axis wind turbine bladesCoupled flap-lag-torsion equations of motion of an isolated horizontal axis wind turbine (HAWT) blade have been formulated. The analysis neglects blade-tower coupling. The final nonlinear equations have periodic coefficients. A new and convenient method of generating an appropriate time-dependent equilibrium position, required for the stability analysis, has been implemented and found to be computationally efficient. Steady-state response and stability boundaries for an existing (typical) HAWT blade are presented. Such stability boundaries have never been published in the literature. The results show that the isolated blade under study is basically stable. The tower shadow (wake) has a considerable effect on the out-of-plane response but leaves blade stability unchanged. Nonlinear terms can significantly affect linearized stability boundaries; however, they have a negligible effect on response, thus implying that a time-dependent equilibrium position (or steady-state response), based completely on the linear system, is appropriate for the type of HAWT blades under study.
Document ID
19800028946
Document Type
Reprint (Version printed in journal)
Authors
Kottapalli, S. B. R. (California Univ. Los Angeles, CA, United States)
Friedmann, P. P. (California, University Los Angeles, Calif., United States)
Rosen, A. (Technion - Israel Institute of Technology Haifa, Israel)
Date Acquired
August 10, 2013
Publication Date
December 1, 1979
Publication Information
Publication: AIAA Journal
Volume: 17
Subject Category
STRUCTURAL MECHANICS
Funding Number(s)
CONTRACT_GRANT: NSG-3082
Distribution Limits
Public
Copyright
Other