Three-Dimensional Hypersonic Laminar Boundary-Layer Computations for Transition Experiment Design

The stability of boundary layers on sharp-nosed cones with elliptical cross sections is assessed using linear stability theory and crosse ow correlations. The objective is to identify a cone guration for wind-tunnel testing that exhibits signie cant crosse ow but also possesses a sufe cient laminar region for boundary-layer stability probing. Parabolized Navier ‐Stokes computer codes were used to calculate the mean e ow about cones with eccentricities of 1.5:1, 2.0:1, and 4.0:1 at a freestream Mach number of 7.95 and freestream unit Reynolds number of 3:3 £ 10 6 m i 1 . Correlations indicated that transition was possible on each cone guration at the above conditions. All three cone gurations showed unstable, ine ectional velocity proe les and boundary-layer thickening along the centerline (minor axis) due to the ine ux of low-momentum e uid. Crosse ow separation was observed on the 2.0:1 cone guration. Linear stability theory was used to calculate stationary crosse ow N factors on all three cone gurations, and to calculate traveling-wave N factors on the 1.5:1 and 2.0:1 cone gurations. All three cone gurations showed crosse ow instability, with the 4.0:1 cone guration attaining the highest N factors. The 1.5:1 and 2.0:1 cone gurationswere unstable to a broad spectrum of traveling waves, with thehighest Nfactors attained on centerline, due to the unstable proe les there.

[1]  R. Kimmel,et al.  On hypersonic boundary-layer stability , 1992 .

[2]  D. Chaussee,et al.  An upwind algorithm for the parabolized Navier-Stokes equations , 1986 .

[3]  Egon Stanewsky,et al.  Boundary-layer transition on swept cylinders at hypersonic speeds , 1996 .

[4]  Leslie M Mack.  Boundary-Layer Stability Analysis for Sharp Cones at Zero Angle-of-Attack , 1986 .

[5]  J. A. Masad,et al.  Three-dimensional boundary-layer transition on a swept wing at Mach 3.5 , 1995 .

[6]  M. S. Chong,et al.  Topology of flow patterns in vortex motions and turbulence , 1994 .

[7]  A. R. Saydah,et al.  Effect of spherical roughness on hypersonic boundary-layer transition. , 1966 .

[8]  Helen L. Reed,et al.  Use of transition correlations for three-dimensional boundary layers within hypersonic flows , 1995 .

[9]  V. Dicristina,et al.  Three-dimensional laminar boundary-layer transition on a sharp 8 degcone at Mach 10 , 1969 .

[10]  William S. Saric,et al.  Stability of three-dimensional boundary layers , 1989 .

[11]  Kenneth F. Stetson,et al.  Laminar boundary layer stability experiments on a cone at Mach 8. I - Sharp cone , 1983 .

[12]  T. Herbert,et al.  Method for Transition Prediction in High-Speed Boundary Layers , 1993 .

[13]  Kenneth F. Stetson,et al.  Laminar boundary layer stability experiments on a cone at Mach 8. III - Sharp cone at angle of attack , 1985 .

[14]  William L. Oberkampf,et al.  Experimental aerodynamics research on a hypersonic vehicle , 1993 .

[15]  Kenneth F. Stetson.  Hypersonic Laminar Boundary Layer Transition. Part 1. Nosetip Bluntness Effects on Cone Frustum Transition. Part 2. Mach 6 Experiments of Transition on a Cone at Angle of Attack , 1982 .