VORTICES ON AN OGEE NOSE-CONE AT INCIDENCE: UPPER SURFACE
On a highly swept thin wing at incidence, flow separation over a blunt but slender body presents, when
placed at a high angle to the wind, an organized structure characterized by two symmetrical and steady
vortices. It is the case for an axisymmetrical ogee nose cone, on which the vortices (in white on the image
shown here) join up without being separated by a vortex-free median zone. Thanks to an illumination limited to a
thin slit, it is possible to obtain a cross section view (shown in the next
image), where the flow is visualized by air bubble suspended in the water, and the vortices are highlighted
by colored emissions.
Image created by Henri Werlé. Reproduced with permission from his spectacular
collection Courants et Couleurs published in 1974 by ONERA, the French Aerospace Lab.
For further information, see
On the Flow of Fluids Made Visible,
Leonardo, Vol. 8, No. 4. (Autumn, 1975), pp. 329-331.