Hostname: page-component-cd9895bd7-gbm5v Total loading time: 0 Render date: 2024-12-22T11:34:26.396Z Has data issue: false hasContentIssue false

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 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Wallis, R.A. The use of air jets for boundary-layer control, ARL, Melbourne, Australia, June 1952, Aero Note 110.Google Scholar
2. Wallis, R.A. A preliminary note on a modified type of air jet for boundary-layer control, ARC CP 513,1960.Google Scholar
3. Freestone, M.M. Preliminary tests at low speed on vorticity produced by air-jet vortex generators, RM 85/1, Centre for Aeronautics, City University, 1985.Google Scholar
4. Pearcey, H.H., Rao, K. and Sykes, D.M. Inclined air-jets used as vortex generators to suppress shock induced boundary layer separation, AGARD-CP-534, 1993, paper 40.Google Scholar
5. Henry, F.S. and Pearcey, H.H. Numerical model of boundary layer control using air-jet generated vortices, AIAA J, 1994, 32, (J2), pp 24152425.Google Scholar
6. Innes, F., Pearcey, H.H. and Sykes, D.M. Improvement in the performance of a three element high lift system by the application of airjet vortex generators, Proc CEAS European Forum, High Lift and Separation Control, University of Bath, UK, 29-31 March, pp 25.125.11, Royal Aeronautical Society, London, 1995.Google Scholar
7. Akanni, S.D. and Henry, F.S. Numerical modelling of air jet vortex generators in turbulent boundary layers, Proc. CEAS European Forum, High Lift and Separation Control, University of Bath, UK, 29-31 March, pp 16.116.12, Royal Aeronautical Society, London, 1995.Google Scholar
8. Oliver, A.G. Air Jet Vortex Generators for Wind Turbines, PhD thesis, Centre for Aeronautics, City University, December 1997.Google Scholar
9. Küpper, C. A Study of the Application of Air-Jet Vortex Generators to Intake Ducts, PhD thesis. Centre for Aeronautics, City University, July 1999.Google Scholar
10. Peake, D.J., Henry, F.S. and Pearcey, H.H. Viscous flow control with air-jet vortex generators, 17th AIAA Applied Aerodynamics Conference, Norfolk, Virginia, 28 June to 1 July 1999, Paper No AIAA 99-3175.Google Scholar
11.CFX 4 user manual, CFX4.1 Release 4.1, CFDS, AEA Industrial Technology Harwell Lab, Oxfordshire, UK, October 1995.Google Scholar
12. van doormal, J.P. and Raithby, G.D. Enhancements of the SIMPLE method for predicting incompressible fluid flows, Numer, Heat transfer, 1984,7, pp 147163.Google Scholar
13. Eriksson, L.E. Generation of boundary-conforming grids around wing body configurations using transfinite interpolation, AIAA J, 1982, 20, (10), pp 13131320.Google Scholar