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Optimising wing lift distribution to minimise wake vortex hazard

Published online by Cambridge University Press:  04 July 2016

W. R. Graham
W. R. Graham*
Affiliation:
Department of EngineeringUniversity of Cambridge, UK
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Abstract

The aim of this work is to investigate how the wake vortex hazard generated by an aircraft can be reduced by modifying the wing lift distribution. The wake associated with a given lift distribution is simulated with a two-dimensional, in viscid ‘vortex method’. A numerical optimisation technique is used to guide the modifications so that a hazard measure, based on the rolling moment induced on a following aircraft encountering the wake, is minimised. The results show that a significant (~20–25%) reduction in hazard compared with conventional high-lift configurations can be achieved, via lift distributions that have a local minimum between the regions contributing to the flap and tip vortices. The counter-signed vorticity associated with this minimum appears to prevent the tip and flap vortices from merging, resulting in a safer wake. Furthermore, the hazard reduction is robust to variations in other features of the lift distribution and should thus be achievable in practice.

Type
Research Article
Information
The Aeronautical Journal , Volume 106 , Issue 1062 , August 2002 , pp. 413 - 426
Copyright
Copyright © Royal Aeronautical Society 2002 

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