Dynamics of the Wake Vortices of a Two-aircraft Formation, Hazard Assessment at Large Distances and Sensitivity Analysis

Extended formation flight is foreseen to be a viable technique for fuel consumption reduction in commercial aviation. It is based on a follower tracking the wake of a leader while maintaining a constant adequate separation. This leads however to different wake dynamics compared to those of the wake of an isolated aircraft. The uncertainty on the relative position between the follower and the wake of the leader further increases the analysis of the underlying vortex dynamics. Using Large Eddy Simulations, this paper presents a methodology to quantify the impact of that uncertainty on the propagation of the formation wake. Midway between a vortex method and grid-based CFD, the Vortex Particle-Mesh method combined the Immersed Lifting Lines is particularly well suited for the simulation of such long-lasting structures. The proposed methodology combines 3D Space Developing and 3D Time Developing simulations to capture the roll-up of the vortex sheets originating from the leader and the follower, their mutual interactions and their long term evolution in a turbulent environment. Simulations are performed for several formation flight configurations around a reference in order to produce a probabilistic representation for the wake propagation. Statistics on the wake vortices characteristics are deduced and are compared to the wake properties of an isolated aircraft.

Affiliations

UCLouvainSST/IMMC/TFL - Thermodynamics and fluid mechanics

Citations

APA
Chicago
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Ransquin, I., Duponcheel, M., & Chatelain, P. (2022). Dynamics of the Wake Vortices of a Two-aircraft Formation, Hazard Assessment at Large Distances and Sensitivity Analysis. AIAA Paper, SCITECH 2022 Forum, 2022-1198. https://doi.org/10.2514/6.2022-1198 (Original work published 2022)