Axisymmetric Flow over a Sphere Cone at Mach 20

Mach 20, perfect-gas flow over a spherically-blunt 5-deg sphere-cone nosetip of a generic reentry vehicle (RV) at a flight altitude of 100 kft and zero angle of attack. Additional assumptions include an isothermal wall-temperature of 500 R, a nose radius of 0.5 inch, and a total nosetip length of 1.25 inch. Very fine grid spacing at the wall was used, resulting in a grid spacing of 4.2×10-8 inch at the nosetip stagnation point.

Computational Grid: Computational grid used consisted of 101 body-normal grid points and 51 streamwise grid points in the blunt-body FNS (Full Navier-Stokes) Zone (Zone 1), and 101 body-normal grid points and 26 streamwise grid points in the afterbody PNS (Parabolized Navier-Stokes) Zone (Zone 2).

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: Total clock time used in this computation with fully dynamic flowfield and residual display was 1 hr and 13 min, while the same computations took less than 35 min with a less graphically-intensive interactive display.

Predicted Flowfield:

(a) Snapshot of the predicted temperature contours in the blunt-body region, and convergence history while the numerical solution is in progress.


(b) Predicted temperature contours over the entire nosetip region, including the FNS blunt-body region as well as the PNS afterbody region.