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David E. Munday wrote:

On Mon, 13 Sep 1999 11:20:16 -0700, Paul <rotaryeng@earthlink.net>
wrote:

David E. Munday wrote:

Circulation is defined in terms of a line-integral about a line which
encircles the surface.  That's what the arrows indicate.

What do you get out of that integration David?
A net flow value? It looks like a distance times a Velocity.

Damned if I know, but if you multiply it by density and free-stream
velocity you get a value for lift.

If memory serves, Gamma (Circulation) is a line integral of the cross
product of the local velocity with a vector along the line where the
line encircles the immersed surface (The airfoil or in this case
radiator element)  There's probably a constant or two in there too.

Check me on this.  Have a look at the first chapter of Abbott and
Doenhoff's Theory of Wing Sections.  You probably already have it on
your shelf just for the graphical data on NACA airfoils tabulated in
it.

As near as I can figure, the circulation theory of lift arose out of
Magnus's studies.  Remember Magnus?  He was the guy trying to figure
out why his artillery shells went long in a wind from the right and
short in a wind from the left.  For a case of a rotating cylinder in a
transverse flow, Gamma collapses to a nice form and it predicts the
lift nicely.

Note:  I assume the connection between Magnus and the Circulation
theory only based on an article by Reimar Horten I was failing to
translate from German.  Yoram Leshinski sent it to me already half
translated and I raised it to 51% or 52%.  There's a CFD Post-Doc
upstairs from me who is a native speaker of German.  I ought to see if
I can get him to make more sense out of it.

______________________________________________________________________
David E. Munday                        
Dept. of Mechanical Engineering         Web: http://www.engr.uky.edu/~munday
521 CRMS Building                       Voice:    (606) 257-3263
University of Kentucky                  FAX:      (606) 257-3304
Lexington, KY  40506-0108               Office:   202 D. V. Terrell Bldg.

 
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