Would a slotted "wing" work? The early history of aviation is full of crazy designs, so please allow me this one:

A span wise narrow gap in the wing halfway between the leading edge and the trailing edge.

The door to the gap would be aerodynamically balanced, it would open at slow speeds. The gap cross section would be nozzle shaped to accelerate the air from underneath the wing to the top side. Lowering its pressure.

At the wing root and tip there will be no gap.

The idea is similar to slotted flaps and slats, but with the aim of energizing the aft portion of the wing. Thereby combining slats and flaps into one. Would it work?

In other words, it would split the wing into two smaller wings.

I expect the answer to be no, but would love to know why.

Edit: edges below are meant to be curved.



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No, it will not work in the way you plotted it.

First, the corners of the duct should be nicely rounded. With the sharp corners you will get a lot of vorticity, but little lift increase. Actually, lift will drop and drag will go up.

Next, a gap works best when connected with a contour break, such as that of a slat or a flap. If you round the corners and add a hinge in order to deflect the rear part of the airfoil, then yes, the gap will help to delay flow separation.