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Wake Shapes Behind Wings in Close Formation Flight Near the Ground  

Han Cheolheui (Kyungwon Tech)
Cho Leesang (Department Mechaincal Engineering, Hanyang University)
Cho Jinsoo (Department Mechaincal Engineering, Hanyang University)
Publication Information
Journal of Mechanical Science and Technology / v.19, no.2, 2005 , pp. 674-681 More about this Journal
Abstract
The unsteady evolution of trailing vortex sheets behind wings in close formation flight near the ground is simulated using a discrete vortex method. The ground effect is included by an image method. The method is validated by comparing computed results with other numerical results. For a lifting line with an elliptic loading, the ground has an effect of moving wingtip vortices laterally outward and suppressing the development of vortex evolution. The gap between wings in close formation flight has an effect of moving up wingtip vortices facing each other. For wings flying in parallel, the ground effect causes the wingtip vortices facing each other to move up, and it makes the opposite wing tip vortices to move laterally outward. When there is a relative height between the wings in ground effect, right-hand side wingtip vortices from a mothership move laterally inward.
Keywords
Formation Flight; Ground Effect; Aircraft Wake Vortices; Discrete Vortex Method;
Citations & Related Records

Times Cited By Web Of Science : 1  (Related Records In Web of Science)
Times Cited By SCOPUS : 1
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