Investigation of the Vortex Dynamics of a Landing Commercial Aircraft to Reduce the Range of Wake Vortices Using Disturbance Elements

• Applicants: Professor Dr.-Ing. Sven Grundmann; Dr. Frank Holzäpfel
• Subject Area: Fluid Mechanics
• Term: since 2026
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 577935025

The proposed research project investigates the decay of wake vortices generated by large commercial aircraft during landing, with the aim of increasing flight safety and improving airport capacity. Wake vortices arise from the lift at the wings and represent a particular risk near the ground, as they can induce strong rolling moments on following aircraft. Previous studies have shown that so-called plate lines – plates installed perpendicular to the runway – accelerate the decay of these vortices and thus reduce their lifetime. This could enable a reduction of the prescribed minimum separation between landing aircraft without compromising safety. In the preceding project, fundamental towing-tank experiments were carried out that yielded important insights into vortex decay with and without ground effects. The present proposal builds on these results and combines laboratory experiments, existing data of field measurements (International Airport Vienna), and numerical simulations to systematically assess the effect of plate lines. Special emphasis is placed on the processes of ground linking – the interaction of vortices with the ground – as well as on end effects, both of which play a central role in vortex decay. Specifically, landing approaches will be simulated in the towing tank to capture the time-resolved velocity field of vortices with and without plate lines using advanced laser measurement techniques. In parallel, extensive numerical simulations will be performed at both model and full scale (e.g., for A320 aircraft at Vienna Airport). These simulations will account for the interactions between plate lines, wake vortices, and atmospheric influences such as crosswind and turbulence. By comparing experimental, field, and simulation data, the project aims to establish a deep physical understanding of the vortex decay mechanisms. The results will be integrated into a probabilistic prediction model that realistically represents vortex evolution under varying boundary conditions. This model will enable the assessment of safety risks for following aircraft as well as for novel aerial vehicles such as air taxis and drones, and it will support the development of recommendations for the optimal deployment of plate lines at airports. In the long term, the project offers the prospect of reducing aircraft separation distances on final approach by up to 20 %, thereby increasing the capacity of congested airports. At the same time, it will enhance overall safety by mitigating or avoiding hazardous vortex configurations.

• DFG Programme: Research Grants