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Normal shock wave-turbulent boundary-layer interactions in the presence of streamwise slots and grooves

Published online by Cambridge University Press:  04 July 2016

A. N. Smith
Affiliation:
Engineering Department, University of Cambridge, UK
H. Babinsky
Affiliation:
Engineering Department, University of Cambridge, UK
J. L. Fulker
Affiliation:
Centre for Aerospace Technology, QinetiQ, Bedford, UK
P. R. Ashill
Affiliation:
Cranfield College of Aeronautics, Bedfordshire, UK

Abstract

The effect of streamwise slots and grooves on a normal shock wave-turbulent boundary-layer interaction has been investigated experimentally at a Mach number of 1.3. The surface pressure distribution for the controlled interaction in the presence of slots featured a distinct plateau. This was due to a change in shock structure from a typical unseparated normal shock wave-boundary-layer interaction to a large bifurcated lambda type shock pattern. Velocity measurements downstream of the slots revealed a strong spanwise variation of boundary-layer properties, whereas the modified shock structure was found to be relatively two-dimensional. Cross flow measurements indicate that slots introduce streamwise vortices into the flow. When applied to an aerofoil, streamwise slots have the potential to reduce wave drag while incurring only small viscous penalties. In the presence of grooves the interaction was initially found to be significantly different. A bifurcated shock structure was observed but the trailing leg appeared stronger and featured a second lambda foot. Oil flow visualisation also revealed differences in the interactions, with the region of suction and blowing being limited to a smaller extent of the grooved control surface. The amount of crossflow present was reduced compared to the slotted control surface. By varying the internal geometry of the grooves it was found that the interaction could be modified to be similar to that in the presence of slots indicating that a more practical control device can be designed.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2002 

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References

1. Fulker, J.L. and Simmons, M.J. An experimental investigation of passive shock/boundary-layer control on an aerofoil, notes on numerical fluid mechanics, 56, Euroshock-drag reduction by passive shock control, edited by Stanewsky, E., Delery, J., Fulker, J. and Geissler, W. Vieweg, 1997, pp 379386.Google Scholar
2. Rosemann, H., Knauer, A. and Stanewsky, E. Experimental investigation of the transonic airfoils DA LVA1-1A and VA-2 with shock control, notes on numerical fluid mechanics, 56, Euroshock-drag reduction by passive shock control, edited by Stanewsky, E., Delery, J., Fulker, J., and Geissler, W. Vieweg, 1997, pp 355378.Google Scholar
3. Raghunathan, S. Passive control of shock-boundary-layer interaction, progress in aerospace sciences, 25, 1988, pp 271296.Google Scholar
4. Delery, J.M. Shock phenomena is high speed aerodynamics: still a source of major concern, Aeronaut J, Jan 1999, pp 1934.Google Scholar
5. Bohning, R. and Doerffer, P. Hybrid and active control of the shock wave-turbulent boundary-layer interaction and porous plate transpiration flow, Euroshock II final technical report, contribution of Karlsruhe University, July 1999.Google Scholar
6. Fulker, J.L. and Simmons, M.J. An investigation of active, suction, shock and boundary-layer control techniques, Euroshock II TR CT95- 0095/3.1, Jan 1999.Google Scholar
7. Ashill, P.R. and Fulker, J.L. A review of flow control research at DERA, Proceeding of IUTAM Symposium on mechanics of passive and active flow control, Kluwer Academic Publishers, 1999, pp 4356.Google Scholar
8. Stanewsky, E. Adaptive wing and flow control technology, Progress in Aerospace Sciences, 2001, 37, pp 583667.Google Scholar
9. Thiede, P. and Dargel, G. Assessment of shock and boundary-layer control concepts for hybrid laminar flow wing design, Euroshock II TR BRPR-95-0076, Sep 1999.Google Scholar
10. Smith, A.N., Babinsky, H., Fulker, J.A. and Ashill, P. Control of normal shock wave-turbulent boundary-layer interaction using stream-wise slots, AIAA 2001-0739.Google Scholar
11. Atkin, C.J. and Squire, L.C. A study of the interaction of a normal shock wave with a turbulent boundary-layer at Mach numbers between 1-3 and 1-55, Euro J of Mechanics BIFluids, 11, (1), 1992, pp 93118.Google Scholar
12. Gibson, T.M., Babinsky, H. and Squire, L.C. Passive control of shock wave boundary-layer interactions, Aeronaut J, Mar 2000, pp 129140.Google Scholar
13. Sun, C. and Childs, M.E. A modified wall wake velocity profile for turbulent compressible boundary-layers, J Airc, 10, (6), 1970, pp 381383.Google Scholar
14. McCormick, D.C. Shock-boundary-layer interaction control with vortex generators and passive cavity, AIAA J, 31, (1), 1993, pp 9196.Google Scholar
15. Saida, N. and Tomizuka, Y. Passive control of shock-boundary-layer interaction, Proceedings of the 22nd International Symposium on Shock Waves, Imperial College London, July 1999.Google Scholar