Hi Charles.

03-Nov-03 07:32:02, Charles Angelich wrote to Tom Walker

 CA> No dongle at all. Check for "air amplifier" then
"entrainment" and
 CA> you should find what I am referring to. A jet of air pulls other
 CA> air along with it which increases the volume of air being moved.

yeah, but a fan with no shroud doesn't produce a jet.

What tends to happen with no shroud (or other duct around the fan)  is that
air circulated from the front of the fan round the side to the back    of
the fan reducing the efficiency of the fan.

this "entrainment" needs a focussed jet and free space longer than the
diameter of the jet before the effect becomes significant,  and you won't
find those conditions in an engine bay.


 -=> Bye <=-

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