Critical Angle of Incidence for the Flow around Spheroids.

Calculating boundary layers along symmetry lines for inclined spheroids, it is found that an increase in the angle of incidence at constant ratio of the half axes induces a jump of the leeward separation point from the rear to the nose. This critical angle for moderately slender bodies is about 42 deg. The variation of the ratio of the half axes shows at times considerable differences in the range of the critical angle of incidence for blunt spheroids of this value, compared with those given in the literature. A comparison between the results in this region using an integral method and the difference method presented here gives acceptable agreement. For slender spheroids, a decrease in the critical angle is obtained - which is reasonable due to the increasing pressure gradient of the inviscid flow around slender bodies.