Suppose we do that, and we do it in such a way as to generate uniform airflow across the wing (by channelling it). And we start the whole contraption up. Does the aircraft rise vertically?
No. The rearward vector of the thrust provided by the fan will provide forward propulsion. If you intend to provide enough thrust to cause adequate airflow over the entire airfoil to develop lift, you're going to be providing enough thrust to drive the entire vehicle forward, too; it's not a vertical operation, but a forward operation while developing lift.
Some here want to say that can't possibly happen.
What do you think?
I think you're still playing spin doctor with ridiculous theories. You might be alluding to coanda effect and attempting to reinvent the airplane and helicopter, but you're mixing your efforts and disregarding basic physics.
You're dangerously close to resurrecting the old treadmill hypothesis, which had no merit from the start. Your attempt at a parallel with a wind tunnel is without merit.
While certain aircraft have used bleed air injected along the top edge of the airfoil to enhance boundary layer aerodynamics, and various devices such as slats and slots are used to enhance boundary layer aerodynamics or delay separation, and some multi engine airplanes do benefit from propeller airflow over the wing to some degree, mounting engines or fans over the span of the wing to produce wing lift vertically isn't happening.
While I suspected early-on that you had some clue whence you speak on these matters, I'm more and more convinced that you're neither pilot nor engineer, and appear to be tossing smoke in the air for lack of something intelligent to offer. Your posts are tantamount to flame-bait.
Loma, consider. A mass of air is accelerated towards the engine inlet duct (by sucking). Some of it goes in the duct, some of it goes around. But it all gets stopped (relative to the aircraft); the stuff inside by plates, the stuff outside by encountering reverse-velocity air (formerly the stuff inside).
You have to put energy in to stop all that air, but stopped it gets.
Now, that air had momenttum. All that momentum goes somewhere (conservation of, and so on). Where does it go? If you have designed things cleverly, it goes into force. In which direction? The same: negative-x (that is what conservation of momentum means). That negative-x direction force is experienced as braking by the airplane+occupants.
The mass of air accelerated toward the engine duct occurs in part by "sucking," and in part by ram effect (hence the term, "ram drag."). The airflow outside the nacelle is irrelevant. Whether it it is accelerated or not by reverse ran gas flow is irrelevant.
The function of reverse gas flow (by blocker doors or cascade vanes) is that of Newton's third law. The opposite reaction to vectoring gas flow forward is a retarding force which contributes to what we experience as "reverse thrust." The reverse flow diverted fan and exhaust gasses do not push against the free airstream outside the nacelle, in order to slow down. While an interaction with the diverted airflow will certainly occur, that interaction doesn't contribute to slowing the airplane down during reverse thrust operations.
The second means of assisting the braking of the aircraft is to increase the engine nacelle drag (frontal area of the engine) by slowing the air down that passes through the engine without producing significant forward thrust or turning the reverser air forward enough to cause reingestion.
Frontal area isn't the issue, nor the equation: this isn't a flat-plate drag issue.
You're probably already familiar with the concept of a windmilling propeller causing substantially more drag in a light twin than a stopped prop: you're hopefully also familiar with the fact that the windmilling propeller produces more drag than a flat plywood disc of the same diameter as the propeller. The issue, then, isn't simply frontal area or flat plate aerodynamics.
While energy is extracted from the slipstream to rotate a propeller and engine, and all it's associated drag, the effects of the turbine engine are substantially more complex with respect to the energy extracted. This extraction occurs at multiple points during entry and processing of the mass airflow, from the inlet through the compressor and diffuser and turbine, to say nothing of the fan itself.
Disregarding airflow through the engine and it's various complexities, consider only the airflow through the fan, bypassing the core. The fan acts as a series of propeller blades or airfoils, each one producing "lift" in a rearward direction: thrust. A function of the production of lift in an airfoil is also induced drag. Airflow through the fan isn't simply imparted energy to thrust without any loss; that loss occurs as drag across the fan. This is but one of many areas in which energy is absorbed in the engine, or lost from the airstream, which account for the difference between gross thrust and net (usable) thrust. That difference is properly termed "ram drag," and is a collective figure comprising various components of drag.
If the reduction of the engine reverser efflux is done at low aircraft speed and low thrust settings, the pilot should perceive no changes in retarding force.
Very little benefit will be perceived (or found) at slower speeds. The disparity between gross and net thrust diminishes as ram drag diminishes, at lower power settings and lower speeds, just as previously shown.
When at a standstill, the only tangible retarding force, or reverse force, will be the redirected fan or gas flow.
It's called powered lift. The FAA has even proposed a set of regulations for large airplanes using that principle.
Powered lift is entirely different: that's the V-22 Opsrey, and other aircraft of the same pattern design.