Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-17T19:15:05.614Z Has data issue: false hasContentIssue false

Some features of steady separated flow from low speed to hypersonic

Published online by Cambridge University Press:  03 February 2016

S. L. Gai*
Affiliation:
School of Aerospace and Mechnical Engineering, Canberra, Australia

Extract

Steady non-vortex shedding base flow behind a bluff body is considered. Such a flow is characterised by the flow separation at the trailing edge of the body with an emerging shear layer which reattaches on the axis with strong recompression and recirculating flow bounded by the base, the shear layer, and the axis.

Steady wake flows behind a bluff body at low speeds have been studied for more than a century (for example, Kirchhoff; Riabouchinsky). Recently, research on steady bluff body wake flow at low speeds has been reviewed and reinterpreted by Roshko. Roshko has also commented on some basic aspects of steady supersonic base flow following on from Chapman and Korst analyses.

In the present paper, we examine the steady base flow features both at low speeds and supersonic speeds in the light of Roshko’s model and expand on some further aspects of base flows at supersonic and hypersonic speeds, not covered by Roshko.

Type
Technical note
Copyright
Copyright © Royal Aeronautical Society 2008 

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. Kirchhoff, G., Zur Theorie freier, 1869, Flussigkeitstrahlen, Crelle 70, 416.Google Scholar
2. Riabouchinsky, D., On steady fluid motion with free surfaces. Proceedings of London Mathematical Society, 1920, Series 2, 19, pp 206215.Google Scholar
3. Roshko, A., Free shear layers, base pressure, and bluff body drag, Symposium on Developments in Fluid Dynamics and Aerospace Engineering, 1993, Bangalore, India.Google Scholar
4. Roshko, A., Perspectives on bluff body aerodynamics, J Wind Eng & Industrial Aerodynamics, 1993, 49, pp 79100.Google Scholar
5. Chapman, D.R., Kuehn, D.M. and Larson, H.K., Investigation of separated flows in supersonic and subsonic streams with emphasis on the effects of transition, 1957, NACA Rept 1356.Google Scholar
6. Korst, H.H., A Theory for base pressures in transonic and supersonic flow, J Applied Mechanics, 1956, 23, pp 593600.Google Scholar
7. Govinda Ram, H.S. and Arakeri, V., Studies on unsteady pressure fields in the region of separating and reattaching flows, ASME J Fluids Engineering, 1990, 112, pp 402408.Google Scholar
8. Elliott, G.S. and Samimy, M., Compressibility effects in shear layers, Physics of Fluids, 1990, Series A, 2, pp 12311240.Google Scholar
9. Eaton, J.K. and Johnston, J.P., A review of research on subsonic turbulent flow reattachment, AIAA J, 1981, 19, (9), pp 10931100.Google Scholar
10. Bradshaw, P. and Wong, F.Y.F., The reattachment and relaxation of a turbulent shear layer, J Fluid Mech, 1972, 52, pp 113135.Google Scholar
11. Arie, M. and Rouse, H., Experiments on two-dimensional flow over a normal wall, J Fluid Mech, 1956, 1, pp 129141.Google Scholar
12. Tani, I., Iuchi, M. and Komoda, H., Experimental investigation of flow separation associated with a step or groove, 1961, Aero Res Inst University of Tokyo, Tokyo, Japan, Rept 364.Google Scholar
13. Mueller, T.J. and Robertson, J.M., A study of mean motion and turbulence downstream of a roughness element, 1962, Proceedings of First Southeastern Conference on Theoretical and Applied Mechanics, Galinburg, TN, USA, pp 326340.Google Scholar
14. Smits, A.J. and Dussauge, J.P., Turbulent Shear Layers in Supersonic Flow, 1996, pp 133156, AIP Press, New York, USA.Google Scholar
15. Sirieix, M., Pression de culot et processus de melange turbulent en ecoulement supersonique plan, La Recherche Aéronautique, 1960, 78, pp 1322.Google Scholar
16. Martellucci, A., Trucco, H. and Agnone, A., Measurements of the turbulent near wake of a cone at Mach 6, AIAA J, 1966, 4, (3), pp 385391.Google Scholar
17. Reeves, B.L. and Buss, H.M., A theoretical model of laminar hypersonic near wakes behind blunt-based slender bodies, February 1969, Avco Rept AVSMD 122-69-RR.Google Scholar
18. Batt, R.G. and Kubota, T., Experimental investigation of laminar near wakes behind 20° wedges at M = 6, AIAA J, 1968, 6, (11), pp 20772083.Google Scholar
19. Shang, J.S. and Korkegi, R.H., Investigation of flow separation over a rearward-facing step in a hypersonic stream, AIAA J, 1968, 6, (5), pp 986987.Google Scholar
20. Gai, S.L., Separated high enthalpy dissociated laminar hypersonic flow behind a step – pressure measurements, AIAA J, 1992, 30, (7), pp 19151918.Google Scholar
21. O’Byrne, S.O. PhD thesis, The Australian National University, Canberra, Australia, 2001.Google Scholar
22. Hayne, M.J, Gai, S.L., Mee, D.J., Morgan, R.G. and McIntyre, T.J., Heat transfer and flow behind a step in high enthalpy superorbital flow, Aeronaut J, 2003, 107, (7), pp 435442.Google Scholar
23. Hama, F.R., Experimental studies on the lip shock, AIAA J, 1968, 6, (2), pp 212219.Google Scholar
24. Nash, J.F., An analysis of two-dimensional base flow including the Effect of the approaching boundary layer, 1963, Aeronautical Research Council, UK, R&M No 3344.Google Scholar
25. Tanner, M., Theories for base pressure in incompressible steady base flow, Prog in Aerospace Sci, 1998, 34, pp 423480.Google Scholar
26. Lykoudis, P.S., Laminar compressible mixing behind finite bases, AIAA J, 1964, 2, (2), pp 391392.Google Scholar
27. Chapman, D.R., Laminar mixing of a compressible fluid, 1950, NACA Rept 958.Google Scholar
28. Tanner, M., Steady base flows, Prog in Aerospace Sci, 1984, 21, pp 81157.Google Scholar