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arXiv · 2512.07270

Preliminary Study of the Effects of Leading-Edge Serration on a Two-Section Planar Wing in ground-effect at Low Reynolds Number

Arnold Lafond-Saunierr·Simone Basile·Paloma Pizarro·Kiana Yamamoto·Hassan M. Nagib·Ricardo Vinuesa·Raffaello Mariani
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Abstract

A preliminary study has been conducted on the effects of serration on the leading-edge of a two-element trapezoidal wing placed both out-of- and in-ground effect. Aerodynamic performance and flow behaviour were evaluated numerically and validated experimentally. Results indicate an increase in maximum lift coefficient and stall angle obtained implementing a serrated leading-edge geometry due to the flow being re-energized by the formation of a series of counter-rotating pairs of vortices. Results from the analysis of the wing in ground effect appear less well defined. Both leading-edge geometries -- straight and serrated -- show an increase in efficiency due to the proximity to the ground. The wing with the straight leading-edge geometry shows constant improvement up to stall, whilst numerical results show a significant decrease in lift performance at high angles of attack. This may be caused by the lower-fidelity numerical model implemented at higher angles of attack, thus yielding less accurate results.

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Arnold Lafond-Saunierr, Simone Basile, Paloma Pizarro, Kiana Yamamoto, Hassan M. Nagib, Ricardo Vinuesa, Raffaello Mariani. 2025-12-08. Preliminary Study of the Effects of Leading-Edge Serration on a Two-Section Planar Wing in ground-effect at Low Reynolds Number. https://arxiv.org/abs/2512.07270

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