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Numerical and experimental investigations of air-jet vortex generators in streamwise pressure gradients

Published online by Cambridge University Press:  04 July 2016

N. P. Lewington
Affiliation:
City University London, UK
F. S. Henry
Affiliation:
City University London, UK
D. J. Peake
Affiliation:
City University London, UK
C. Singh
Affiliation:
City University London, UK

Abstract

Numerical and experimental results are presented demonstrating the sensitivity of the performance of air-jet vortex generators (AJVGs) operating at jet to freestream velocity ratios of up to 4 to jet pitch and jet skew. The merits of installing co- or counter-rotational systems are shown. Numerical results for AJVG arrays on a flat plate in a zero pressure gradient indicate optimum values for jet spacing and velocity ratios to enhance the downstream skin friction above the uncontrolled value. The installation of a co-rotating array of AJVGs into a modified NACA 23012 unswept wing and the improvements in the lift and drag performance are illustrated. It is demonstrated that by careful implementation of boundary conditions in relatively straightforward ‘numerical’ experiments it is possible to carry out a sensitivity analysis on the vortex generator arrays before they are implemented in successfully enhancing wing performance.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2001 

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