Re: Jet Engines above the wing: why not used?

From:         podleski@nas.nasa.gov (Steve D. Podleski)
Organization: whoknows
Date:         10 Jun 96 12:22:18 
References:   1 2
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drela@athena.mit.edu (Mark Drela) writes:
[domk1031@cetus.zrz.TU-Berlin.DE (Burkhard Domke) writes:
[|> The flow of engines pod-mounted beneath a wing counteract the
[|> circulation of the wing, thus reducing lift, whereas engines mounted
[|> above the wing would enhance lift.
[
[Careful here.  You cannot relate the lift directly to the circulation if
[blowing is used.  The derivation of the Kutta-Joukowsky relation between
[lift and circulation...
[
[   Lift/span = rho V Gamma

One may not be able to use Kutta-Joukowsky to predict lift with blowing but
blowing does increase lift whether below or above the wing if the blown
air is redirected downward.