Advances in Aircraft and Spacecraft Science Volume 8, Number 2, March 2021 , pages 151-167 DOI: https://doi.org/10.12989/aas.2021.8.2.151 |
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Stall in ground effect using the unsteady vortex lattice method with Kirchhoff-based correction |
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Carlos A. Neves and Pedro J. Boschetti
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Abstract | ||
The goal of this research is to evaluate the stall behavior of a high aspect ratio rectangular wing in ground effect using an unsteady vortex-lattice method with a Kirchhoff-based correction (UVLM-K), including how the lift coefficient achieved in stall is affected by dynamic ground effect. A flow separation algorithm based on the Kirchhoff-Helmholtz theory and a flow separation model presented by Fischenberg are applied. The code was validated using experimental data from previously published works. The stall behavior of a rectangular wing of aspect ratio of 8.587 formed with a NACA 4415 airfoil section was studied in static and dynamic ground effect. To obtain the empirical data required by the UVLM-K, the NACA4415 airfoil was simulated at fixed height aboveground using a finite-volume code solver. The wing simulation results have shown that the lift coefficient achieved by the wing in stall for takeoff and flare maneuvers are lower than those estimated at a fixed height above the ground. It can be concluded, based on the results obtained herein, that the stall behavior of a wing in dynamic ground effect depends on the history of the maneuver. | ||
Key Words | ||
unsteady aerodynamics; stall prediction; ground effect; computational fluid dynamics; take-off and landing; Kirchhoff flow theory | ||
Address | ||
Carlos A. Neves: Department of Mechanical Engineering, Universidad Simón Bolívar, Sartenejas Valley, Caracas 1080-A, Venezuela Pedro J. Boschetti: Department of Industrial Technology, Universidad Simón Bolívar, Camuri Valley, Naiguatá 1163, Venezuela | ||