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arXiv · 1810.07686

Thrust augmentation of flapping airfoils in low Reynolds number flow using a flexible membrane

Justin W. Jaworski·Raymond E. Gordnier
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Abstract

The unsteady aerodynamic thrust and aeroelastic response of a two-dimensional membrane airfoil under prescribed harmonic motion are investigated computationally with a high-order Navier-Stokes solver coupled to a nonlinear membrane structural model. The effects of membrane prestress and elasticity are examined parametrically for selected plunge and pitch-plunge motions at a chord-based Reynolds number of 2500. The importance of inertial membrane loads resulting from the prescribed flapping is also assessed for pure plunging motions. This study compares the period-averaged aerodynamic loads of flexible versus rigid membrane airfoils and highlights the vortex structures and salient fluid-membrane interactions that enable more efficient flapping thrust production in low Reynolds number flows.

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Justin W. Jaworski, Raymond E. Gordnier. 2018-10-17. Thrust augmentation of flapping airfoils in low Reynolds number flow using a flexible membrane. https://doi.org/10.1016/j.jfluidstructs.2014.08.010

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