University of Wisconsin - Madison Seminar (3/05): Powerpoint File.
Geophysical Fluid Dynamics Institute Colloquium (11/04): Powerpoint File, PDF File.
On the left is potential temperature (darker shades indicate higher values) and on the right is total vorticity magnitude (in s^-1)
Total vorticity magnitude for two later times (850 s & 950 s). Note the skew of the plume base to the right at 850 s and to the left at 950 s.
Vertical component of vorticity slightly above the surface (z=45 m) for a range of times encompassing the previous two images. Note the similarity between panel (a) t = 810 s and panel (d) t = 990 s, suggesting that the period of the wake vortex system is ~180-200 s, consistent with the plume asymmetry seen above. First guess at a Strouhal number for the wake system is ~0.25.
Vertical component of vorticity for (a) t = 850 s and (b) t = 950 s, showing the periodic formation of wake vortices on either side of the plume .
Finally, as a point of reference, here is a cartoon of the typical observed structure (from lab experiments) of a non-buoyant jet in a cross flow (taken from Fric & Roshko (1994, J. Fluid Mech., Vol. 279, pp. 1-47).
