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Cavity drag at transonic speeds

Published online by Cambridge University Press:  04 July 2016

L. C. Squire
Affiliation:
Department of Engineering, Cambridge University
S. H. Nasser
Affiliation:
Department of Engineering, Cambridge University

Abstract

This paper presents the results of an investigation of the flow around rectangular and chamfered cavities at high subsonic and low supersonic speeds. Pressures measured on the faces of the cavities are integrated to find the pressure drag of the cavities. The types of cavity tested range from simple sawcuts to cavities so long that the two ends can be regarded as independent and the results for these are compared with the sum of the drags of isolated forward and rear facing steps.

Although the Reynolds numbers of the tests are similar to those in flight conditions the maximum depth of the cavities tested is only 6 mm so that the pressure resolution on the vertical faces of the cavities is limited. In spite of this it is estimated that the maximum error in the drag of any particular cavity is less than the skin friction drag on a smooth surface equal in area to half the plan area of the cavity.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 1993 

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References

1. Wieghardt, K. Increase of the turbulent frictional resistance caused by surface irregularities, MAP R & T No 103, June 1946 (Translation of FB 1563-ZWB 1942).Google Scholar
2. Tillmann, W. Additional measurements of the drag of surface irregularities in turbulent boundary layer, NACA Technical Memorandum 1299, 1951.Google Scholar
3. Roshko, A. Some measurements of flow in a rectangular cut out, NACA Technical Note 3488, 1955.Google Scholar
4. Rossiter, J.E. Wind tunnel experiments on the flow over rectangular cavities at subsonic and transonic speeds, Aeronautical Research Council R & M No 3438, 1964.Google Scholar
5. Winter, K.G. and Gaudet, L. A program of tests on the drag of excrescences proposed for the 8 x 8 ft wind tunnel and a brief analysis of some previous results, Royal Aircraft Establishment, TM 1005, August 1967.Google Scholar
6. Gaudet, L. and Winter, K.G. Measurements of the drag of some characteristic aircraft excrescences immersed in turbulent boundary layer, AGARD Conference on Aerodynamic Drag, CP 124, 1973 Google Scholar
7. Gaudet, L. and Johnson, P. Measurements of the drag of various two-dimensional excrescences immersed in turbulent boundary layer at Mach numbers between 0.2 and 2.8, Royal Aircraft Establishment, Technical Report 70190, 1970.Google Scholar
8. Gaudet, L. and Johnson, P. Measurements of the drag of excrescences immersed in turbulent boundary layer at Mach number between 0.2 and 2.8: circular holes, Royal Aircraft Establishment, Technical Report 71181, 1971.Google Scholar
9. Pallister, K.C. Wind tunnel measurements of transonic drag of excrescences immersed in turbulent boundary layer, Aircraft Research Association, Report No. 37, December 1974.Google Scholar
10. Young, A.D. and Paterson, J.H. Aircraft excrescence drag, AGARDograph No 264, AGARD, 1981.Google Scholar
11. Zhang, X. and Edwards, J.A. Computational analysis of unsteady supersonic cavity flows driven by thick shear layers, Aeronaut J, November 1988, 92, (919), pp 365374.Google Scholar
12. Zhang, X. and Edwards, J.A. An investigation of supersonic oscillatory cavity flows driven by thick shear layers, Aeronaut .J, December 1990, 94, (940), pp 355364.Google Scholar
13. Squire, L.C. and Savill, A.M. Drag measurements on planar riblet surfaces at high subsonic speeds, Applied Scien Res, 1989, 46, pp 229243.Google Scholar
14. Charwat, A.F., Roos, J.N., Dewey, F.C. and Hitz, J.A. An investigation of separated flow, Part I, J Aerospa Sci, 1961, 28, pp 457470 and Part II, J Aerospa Sci,1961, 28, pp 513-527.Google Scholar
15. Sarohia, V. Experimental investigation of oscillations in flows over shallow cavities, AIAA Paper 76-182, 1976.Google Scholar
16. Kendrick, J.F. and Cockrell, Private communication, University of Leicester, 1989.Google Scholar
17. East, L.F. Aerodynamically induced resonance in rectangular cavities, J Sound and Vib, 1966, 3, (3) pp 277287.Google Scholar