4. For the Japanese wind lens turbine, the effect of the shroud
is to reduce the downstream pressure, e.g., in the rotor wake, say
by ?P. Show by modifying the Betz limit, how power production can
actually be greater than the Betz limit. Your power production
should be a function of a = v4/V. Assume v4 and S4 are known. Get
it as close as you can. In the process, recognize that the wind
speed at the rotor plane and...