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http://dx.doi.org/10.5139/JKSAS.2008.36.12.1146

Effects of Torsional Flexibility on a Flapping Airfoil  

Cho, Moon-Sung (한국항공대학교 항공우주 및 기계공학부 대학원)
Bae, Jae-Sung (한국항공대학교 항공우주 및 기계공학부)
Kim, Hark-Bong (한국항공대학교 항공우주 및 기계공학부)
Kim, Woo-Jin (한국항공대학교 항공우주 및 기계공학부 대학원)
Publication Information
Journal of the Korean Society for Aeronautical & Space Sciences / v.36, no.12, 2008 , pp. 1146-1151 More about this Journal
Abstract
In this paper, the effects of torsional flexibility on a flapping airfoil are investigated. The aerodynamic forces of a torsional flexible flapping airfoil is computed using 2-D unsteady vortex panel method. A typical-section aeroelastic model is used for the aeroelsatic calculation of the flapping airfoil. Torsional flexibility and excitation frequency are considered as main effective parameters. Under heavy airfoil condition , the thrust peak is observed at the points where the frequency ratio is about 0.75. Based on this peak criterion, there exists two different motions. One is an inertia driven deformation motion and the other is an oscillation driven deformation motion. Also, in the thrust peak condition, the phase angle is kept 85 degrees, independent of the torsional flexibility and the excitation frequency.
Keywords
Unsteady; Panel Method; Airfoil; Flapping; Torsional Stiffness; Aeroelasticity; Plunge motion;
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