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Annual Review of Fluid Mechanics

Volume 51, 2019

Leading-Edge Vortices: Mechanics and Modeling

Abstract

The leading-edge vortex (LEV) is known to produce transient high lift in a wide variety of circumstances. The underlying physics of LEV formation, growth, and shedding are explored for a set of canonical wing motions including wing translation, rotation, and pitching. A review of the literature reveals that, while there are many similarities in the LEV physics of these motions, the resulting force histories can be dramatically different. In two-dimensional motions (translation and pitch), the LEV sheds soon after its formation; lift drops as the LEV moves away from the wing. Wing rotation, in contrast, incites a spanwise flow that, through Coriolis tilting, balances the streamwise vorticity fluxes to produce an LEV that remains attached to much of the wing and thus sustains high lift. The state of the art of vortex-based modeling to capture both the flow field and corresponding forces of these motions is reviewed, including closure conditions at the leading edge and approaches for data-driven strategies.

Keyword(s): data-driven, leading-edge vortex, LEV, pitching, rotating, surging, translating, unsteady aerodynamics, vortex model
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2019-01-05
2024-04-19
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/content/journals/10.1146/annurev-fluid-010518-040334
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Leading-Edge Vortices: Mechanics and Modeling
Annual Review of Fluid Mechanics 51, 75 (2019); https://doi.org/10.1146/annurev-fluid-010518-040334
/content/journals/10.1146/annurev-fluid-010518-040334
/content/journals/10.1146/annurev-fluid-010518-040334
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