J.A.W. wrote: ↑03 Aug 2021, 00:25
Well presented post there J-A-F, & that pic of the 'lead sled' B-36 in flight, blasting
out massive visible 'cork-screw' vortices from its huge pusher-props gives a clue as
to why birds have flight problems in the vicinity of electric wind-turbine complexes.
btw
these aren't prop tip vortices - and they're not vortices in atmospheric air
anyway max tip vortex pressures from high aspect ratio elements eg prop blades are less than max from low AR wings
the engine's water vapour exhaust naturally condenses by cooling at altitude which is what the photo basically shows
each exhaust stream emerges into a propulsive stream that is being rotated by the prop action
tip pressure lows are detectable, but also the engine core wake, and majorly the rotation of the whole stream
RETRO EDIT NEXT DAY - (credit to Andres for making this point before me)
yes wind turbines work rate is a fraction of propellers work rate ..... because eg .....
the B36 flying at eg 360 mph TAS by per every 10 seconds accelerating mile-long columns of air by (say) 120 mph
the wind turbine is braked to a shut down whenever wind speed exceeds (say) 50 mph .... so ....
propellers develop pressures at least 5 times greater than the wind turbines do
and afaik good news .....
GM now make 220m diameter wind turbines giving higher utilisation % and notionally 12 -14 MW output
PV makers are now making cheaply material working on 3 energy bands including infra red (handy for cloudy UK etc ?)