Effects of leading-edge tubercles on wing flutter speeds

Abstract

Abstract. The dynamic aeroelastic effects on wings modified with bio-inspired leading-edge (LE) tubercles are examined in this study. We adopt a state-space aeroelastic model via the coupling of unsteady vortex-lattice method and a composite beam to evaluate stability margins as a result of LE tubercles on a generic wing.The unsteady aerodynamics and spanwise mass variations due to LE tubercles have counteracting effects on stability margins with the former having dominant influence.When coupled, flutter speed is observed to be 5% higher, and this is accompanied by close to 6% decrease in reduced frequencies as an indication of lower structural stiffness requirements for wings with LE tubercles. Both tubercle amplitude and wavelength have similar influences over the change in flutter speeds, and such modifications to the leading-edge would have minimal effect on stability margins when concentrated inboard of the wing. Lastly, when used in sweptback wings, LE tubercles are observed to have smaller impacts on stability margins as the sweep angle is increased.

Numerical Investigation of Ice Formation on a Wing with Leading-Edge Tubercles

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Aerodynamics with state-of-the-art bioinspired technology: Tubercles of humpback whale

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Investigating Mechanical Response and Structural Integrity of Tubercle Leading Edge under Static Loads

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