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Jetstream Rider (Post #40):
I don't believe that lift can occur without downwash. The first two cases you quote, "spinning cylinder and reflex trailing edge", both turn the wake downwards.
A cylinder spinning backwards and travelling forwards has a delayed boundary layer separation point on the upper surface, where the boundary layer is moving in the same direction as the free stream flow, and a premature separation point on the lower surface where it is moving against the free stream flow. This deflects the whole cylinder wake downwards, i.e. it creates downwash, and hence lift.
This is the same effect as a spin bowler uses to curve the flight of a cricket ball - it works for spheres, too!
An aerofoil wing section with a reflex trailing edge will still generate downwash and lift, simply less of each because it is not an optimum shape for high lift coefficient.
I'm afraid I don't understand what you mean by "lift without power for infinite spans", so cannot comment.
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