Abstract
The incipient separation induced by the shock wave/turbulent boundary layer interaction at the sharp fin is the subject of the present study. Existing theories for the prediction of incipient separation, such as those put forward by McCabe (1966) and Dou and Deng (1992), can thus far only predic the direction of surface streamline and tend to overpredict the incipient separation condition based on the Stanbrook’s criterion. In this paper, the incipient separation is first predicted with Dou and Deng (1992)’s theory and then compared with Lu and Settles’ (1990) experimental data. The physical mechanism of the incipient separation as induced by the shock wave/turbulent boundary layer interactions at sharp fin is explained via surface flow pattern analysis. Furthermore, the reason for the observed discrepancy between the predicted and experimental incipient separation conditions is clarified. It is found that when the wall-limiting streamlines behind the shock wave becomes aligned with one ray from the virtual origin as the strength of the shock wave increases, the incipient separation line is formed at which the wall-limiting streamline becomes perpendicular to the local pressure gradient. The formation of this incipient separation line is the beginning of the separation process. The effects of Reynolds number and Mach number on incipient separation are also discussed. Finally, a correlation for the correction of the incipient separation angle as predicted by the theory is also given.
Similar content being viewed by others
Abbreviations
- A :
-
parameter in the “triangular model”
- C fx :
-
component of local skin friction coefficient in the mainflow (streamwise) direction (dimensionless)
- k :
-
specific heat ratio (dimensionless)
- M :
-
Mach number (dimensionless)
- M ∞(or M 1):
-
incoming Mach number (dimensionless)
- p :
-
static pressure (N/m2)
- R :
-
temperature recovery factor at wall (dimensionless)
- Re θ :
-
Reynolds number based on momentum thickness (dimensionless)
- T :
-
absolute temperature (K)
- u :
-
velocity component in the mainflow direction in the boundary layer (m/s)
- w :
-
velocity component in the crossflow direction in the boundary layer (m/s)
- x :
-
coordinate in the streamwise direction (m)
- y :
-
coordinate in the direction normal to the flat plate (m)
- z :
-
coordinate in the direction normal to the streamwise direction (m)
- α:
-
turning angle of the main flow, measured relative to the direction of velocity vectorat the beginning of interaction (radian or degree)
- β:
-
angle measured from the incoming freestream direction, centred at the virtual origin (near the fin apex) (degree)
- β 0 :
-
angle of shock wave (degree)
- γ w :
-
wall shear angle, i.e. angle between the direction of the wall-limiting streamline and the external streamline direction of boundary layer (degree)
- θ:
-
momentum thickness of boundary layer (m)
- ν:
-
kinematic viscosity (m2/s)
- ν(M):
-
Prandtl–Meyer function (radian), see (7)
- ρ:
-
density (kg/m3)
- σ:
-
α + γ w, turning angle of surface streamline, i.e. the limiting streamline direction on the wall measured from the incoming flow direction (degree)
- τ:
-
shear stress (N/m2)
- e:
-
external of the boundary layer
- i:
-
incipient separation
- p:
-
apex of “triangular model,” Fig.5
- w:
-
at walls
- x :
-
component in the direction of the main flow
- z :
-
component in the direction of the cross-flow
References
Bogdonoff, S.M.: Observation of three-dimensional “Separation” in shock wave turbulent boundary layer interactions, boundary layer separation. In: Proceedings of the IUTAM Symposium, London, pp. 37–55. Springer, Berlin Heidelberg New York (1987)
Delery J.M.(1985). Shock wave/turbulent boundary layer inter- actions and its control. Prog. Aerosp. Sci. 22, 209–280
Delery J.M., Marvin J.G.: Turbulent shock wave/boundary layer interactions. AGARD-AG-280 (1986)
Deng X.-Y., Liao J.-H.(1993). Correlative behaviours of shock wave/boundary layer interaction induced by sharp fin and semicone. AIAA J. 31, 962–963
Deng X.-Y., Liao J.-H., Dou H.-S.: Incipient turbulent separation induced by swept shock wave. AIAA Paper 94-2278 (1994)
Dolling D.S.(2001). Fifty years of shock-wave/boundary-layer interaction research: what next?. AIAA J. 39, 1517–1531
Dou, H.-S.: Experimental and theoretical investigations of 3D shock wave/turbulent boundary layer interactions. PhD Thesis, Institute of Fluid Mechanics, Beijing University of Aeronautics and Astronautics (1991)
Dou H.-S., Deng X.-Y.(1992). Approximate formula of weak oblique shock wave angle. AIAA J. 30, 837–839
Dou, H.-S., Deng, X.-Y.: Experimental investigations of the separation behaviour in 3D shock wave/turbulent boundary-layer interactions. In: Proceedings of the 18th Congress of ICAS (International Council of the Aeronautical Sciences)/AIAA, Beijing, pp.1543–1553 (1992)
Dou H.-S., Deng X.-Y.(1992). Prediction for the incipient separation of fin-induced 3-D shock wave/turbulent boundary-layer interactions(in Chinese with English abstract). Acta Aerodyn. Sin. 10, 45–52
Green J.E.(1970). Interaction between shock waves and boundary layers. Prog. Aerosp. Sci. 11, 235–340
Hopkins E.J., Inouye M.(1971). An evaluation of theories for predicting turbulent skin friction and heat transfer on flat plates at supersonic and hypersonic Mach numbers. AIAA J. 9, 993–1003
Inger, G.R.: Incipient separation and similitude properties of swept shock/turbulent boundary layer interactions. AIAA Paper 86-0345 (1986)
Johnston J.P.(1960). On the three- dimensional turbulent boundary layer generated by secondary flow. ASME J. Basic Eng. 82, 233–248
Knight D.D., Badekas D., Horstman C.C., Settles G.S.(1992). Quasiconical flowfield structure of the 3-dimensional single fin interaction. AIAA J. 30 (12): 2809–2816
Knight D.D., Yan H., Panaras A.G., Zheltovodov A.A.(2003). Advances in CFD prediction of shock wave turbulent boundary layer interactions. Prog. Aerosp. Sci. 39, 121–184
Korkegi R.H.(1973). A simple correlation for incipient turbulent boundary layer separation due to a Skewed shock wave. AIAA J. 11, 1578–1579
Kubota H., Stollery J.L.(1982). An experimental study of the interaction between a glancing shock wave and a turbulent boundary layer. J. Fluid Mech. 116, 431–458
Kuethe A.M., Chow C.Y.(1986). Foundations of aerodynamics: Bases of Aerodynamic Design, 4th edn., pp. 385–423 Wiley, New York
Leung A.W.C., Squire L.C.(1995). Reynolds number effects in swept-shock-wave/turbulent-boundary-layer interaction. AIAA J. 33, 798–804
Lighthill M.J.(1963). Attachment and separation in three dimensional flow. In: Rosenhead L. (eds) Laminar Boundary Layer. Oxford University Press, England, pp. 72-82
Lu, F.K.: Semi empirical extension of McCabe’s vorticity model for fin-generated shock wave boundary-layer interactions. In: Proceedings of the 4th Asian Congress of Fluid Mechanics, pp.A170-A173 The Hong Kong University Press, Hong Kong (1989)
Lu F. K.(1993). Quasiconical Free Interaction between a Swept Shock and a turbulent boundary layer. AIAA J. 31, 686–692
Lu F.K., Settles G.S.(1990). Color surface-flow Visualization of fin-generated shock wave boundary-layer interactions. Exp Fluids 8, 352–354
Lu F.K., Settles G.S., Horstman C.C.(1990). Mach number effects on conical surface features of swept shock-wave/boundary-layer interactions. AIAA J. 28, 91–97
Maskell, E.C.: flow separation in three dimensions. RAE Report No 2625 (1955)
McCabe A.(1966). The three-dimensional interaction of a shock wave with a turbulent boundary layer. Aeronaut. Q. 17, 231–252
Myring D.F.(1977). The effect of sweep on conditions at separation in turbulent boundary-layer/ Shock-Wave interaction. Aeronaut. Q. 28, 111–122
Neumann, R.D., Hayes, J.R.: The effects of test scale and facility characteristics on the flow field features of supersonic three-dimensional fin/plate interactions, AIAA-2002-976. AIAA Aerospace Sciences Meeting and Exhibit, 40th, Reno, NV, 14–17 (2002)
Olcmen M.S., Simpson R.L.(1992). Perspective: on the near wall similarity of three-dimensional turbulent boundary layers. ASME J. Fluid Eng. 114, 487–495
Panaras A.G.(1996). Review of the physics of swept-shock/boundary layer Interactions. Prog. Aerosp. Sci. 32, 173-244
Settles G.S., Dolling D.S.(1992). Swept shock-wave /Boundary-layer interactions. In: Hensch M.J.(eds) Tactical Missile Aerodynamics: General Topics. Progress in Astronautics and Aeronautics, vol. 141. AIAA, Washington, pp. 505–574
Smith, P.D.: An integral prediction method for three dimensional compressible turbulent boundary layer. ARC RM 3739 (1972)
. Stanbrook, A. An experimental study of the glancing inter-action between a shock wave and a boundary layer. British ARC CP-555 (1960)
Swafford T.W., Whitfield D.L.(1985). Time-dependent solution of three-dimensional compressible turbulent integral boundary-layer equations. AIAA J. 23, 1005-1013
Van Oudheusden B.W., Nebbeling C., Bannink W.J.(1996). Topological interpretation of the surface flow visualization of conical viscous/inviscid interactions. J. Fluid Mech. 316, 115–137
White F.M.(1974). Viscous Fluid Flow. McGraw-Hill, New York pp. 542–558.
Zheltovodov A.A., Maksimov A.I., Shilein E.K.(1987). Development of turbulent separated flows in the vicinity of swept shock waves. In: Kharitonov A.M. (eds) The Interactions of Complex 3-D Flows, Akademia Nauk USSR. Institute of Theoretical and Applied Mechanics, Novosibrisk, pp. 67–91
Author information
Authors and Affiliations
Corresponding author
Additional information
Communicated by K. Takayama.
Rights and permissions
About this article
Cite this article
Dou, HS., Khoo, B.C. & Yeo, K.S. Incipient separation in shock wave/boundary layer interactions as induced by sharp fin. Shock Waves 15, 425–436 (2006). https://doi.org/10.1007/s00193-006-0044-z
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00193-006-0044-z