I don't understand where the Coanda effect is coming into play here. From the first cutaway drawing (http://goo.gl/QKOJy), it appears that the outer disk rotates independently of the main hub--possibly powered by the central turbines forcing air outward to the wing? It also shows the air in-take port(s) where you would expect outward thrusting air. And, it seems, like the Coanda effect relies on a more spherical shape, as opposed to the very flat sketch shown. How would that design produce the Coanda effect?

I am basing my questions on what I could glean from Wikipedia and a couple Youtube videos:

http://www.youtube.com/watch?v=WPUAq3QObp4

http://www.youtube.com/watch?v=AqxJe-RMUsI