Study on the wake vortex behavior behind a commercial aircraft during take-off and landing

• Published in: Journal of mechanical science and technology Vol. 38; no. 7; pp. 3487 - 3497
• Main Authors: Ji, Seunghwan, Han, Cheolheui
• Format: Journal Article
• Language: English
• Published: Seoul Korean Society of Mechanical Engineers 01.07.2024; 대한기계학회
• Subjects: Control; Dynamical Systems; Engineering; Industrial and Production Engineering; Mechanical Engineering; Original Article; Vibration; 기계공학; Wake vortex; Ground effect; Fourier-spectral method; Commercial aircraft
• ISSN: 1738-494X; 1976-3824
• DOI: 10.1007/s12206-024-0623-x

Wake vortices generated from the leading large aircraft can exist over runways for a long lifetime and have the possibility of endangering the flight safety of any aircraft following behind. The study on the wake vortex behavior is required to optimize the flight rules and to increase the airport capacity. In the present study, the wake vortex behaviors behind a commercial aircraft during take-off and landing are studied using a Fourier-spectral method. In order to consider the ground effect, a new boundary condition was implemented to the previously developed Fourier-spectral method. We investigated the complex behaviors of wake vortices from the flaps and wingtips near the ground. It was found that, for a co-rotating vortex pair from the flap and the wingtip, the ratio between the core radius and the separation distance is critical for the initiation of the vortex merging. It was also found that the relative strength between vortices affects the behavior of the vortex merging process (the weaker vortex is absorbed by the stronger vortex after the weaker vortex rotating around the center closer to the stronger one). The flight altitude has an effect of accelerating the vortex merging process. When the aircraft is flying at a lower altitude, the vortices close to the ground generated more quickly separation bubbles on the ground by inducing stronger cross flows. The secondary vortex has an effect of accelerating the vortex merging process by reducing the separation distance between the vortices.