Laminar/Turbulent, Afterbody Surface-Heating Predictions at Mach 11.2


Mach 11.2, perfect-gas, wind-tunnel conditions of turbulent flow over a spherically-blunt sphere-cone configuration at a Reynolds number of approximately 11×106/ft. The body geometry consisted of a 5.25-deg sphere-cone, with a nose radius of 0.033 ft and a total body length of approximately 2.45 ft. Wall-temperature was assumed to be 540 R, and the Baldwin-Lomax turbulence model was used to simulate turbulent eddy-viscosity effects.

Computational Grid: Computational grid used consisted of 101 body-normal grid points and 35 streamwise grid points in the blunt-body FNS (Full Navier-Stokes) region (Zone 1), and 101 body-normal grid points and 56 streamwise grid points in the afterbody PNS (Parabolized Navier-Stokes) region (Zone 2). At the wall, very fine grid spacing was used, resulting in a grid spacing at the stagnation point of 3.5×10-8 inch.

PC Hardware Used: Computations were done on a very old 133 MHz Intel Pentium PC, with 1 GB hard disk and 32 Meg RAM.

Computational Time Required: The numerical solution was done in two steps, first with a coarse grid in blunt-body region (Zone 1), and then with a fine grid in the blunt-body region (Zone 1) and the subsequent afterbody region (Zone 2). Total clock time used was approximately 30 min.

Snapshots of Predicted Flowfield:

(a) Predicted laminar surface heat-transfer distribution is compared with laminar experimental data.

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(b) Predicted turbulent surface heat-transfer distribution is compared with turbulent experimental data.

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