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Control of vortical separation on a circular cone

Published online by Cambridge University Press:  04 July 2016

N. J. Mourtos
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Abstract

For conical bodies, at moderate angles of attack, the flow separates from the lee side, forming two vortices. Although the vortex lift contribution is highly desirable, as the angle of attack increases, the vortex system becomes asymmetric, and eventually the vortices breakdown. Thus, some control of the separation process is necessary if the vortex lift is to be exploited at higher angles of attack.

The theoretical model which is used in this analysis has three parts. First, the ‘single line-vortex’ model is used within the framework of ‘slender-body theory’ to compute the outer inviscid field for specified separation lines. Second, the 3-D boundary layer is represented by a momentum equation for the cross-flow, analogous to that for a plane boundary layer and a von Karman/Pohlhausen approximation is applied to solve this equation. The cross-flow separation for both laminar and turbulent layers is determined by matching the pressure at the upper and lower separation points. This iterative procedure yields a unique solution for the separation lines and consequently for the positions of the vortices and the vortex lift on the body. Third, control of separation is achieved by blowing tangentially from slots located symmetrically along cone generators.

Type
Research Article
Information
The Aeronautical Journal , Volume 94 , Issue 936 , July 1990 , pp. 213 - 219
Copyright
Copyright © Royal Aeronautical Society 1990 

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References

1. Wood, N. J. and Roberts, L. The control of vortical lift on delta wings by tangential leading edge blowing, AlAA paper no. 87-0158, January 1987.Google Scholar
2. Mourtos, N. J. Control of vortical separation on conical bodies, PhD Thesis, Department of Aeronautics and Astronautics, Standford University. Also: Stanford/NASA Ames Joint Institute for Aeronautics and Acoustics TR-78.Google Scholar
3. Bryson, A. E. Symmetric vortex separation on circular cylinders and cones, J Appl Mech, December 1959.Google Scholar
4. Jones, R. T. Properties of Low Aspect Ratio Pointed Wings at Speeds Below and Above the Speed of Sound, NACA report no. 835, 1946. Also: NACA TN-1032, 1946.Google Scholar
5. Schlichting, H. Boundary Layer Theory, McGraw Hill Inc, San Francisco, 1979, p 206.Google Scholar
6. Friberg, E. G. Measurement of vortex separation, Part I: Two-dimensional circular and elliptic bodies, MIT TR-114, August 1965.Google Scholar
7. Friberg, E. G. Measurement of vortex separation, Part II: Two-dimensional circular and elliptic bodies, MIT TR-115, August 1965.Google Scholar
8. Jorgensen, L. H. Elliptic Cones alone and with wings at supersonic speeds, NACA TN-4045, October 1957.Google Scholar
9. Roberts, L. A theory for turbulent curved wall jets, AlAA paper no. 87-0004, January 1987.Google Scholar
10. Smith, J. H. B. Improved calculations of leading edge separation from slender, thin, delta wings, Proc R Soc, 1968, 306, pp 67–90.Google Scholar