PierreB
February 27, 2020, 12:52pm
25
Some indications of the current Kiwee are on
For kiwee one flight angle is depending on wind speed. Flight angle at 10m/s windspeed is greater Than 60deg. At that speed, our theoretical extracted power is around 240 watts (by memory). Our measured extracted power is around 210 watts. Wind turbine Drag is about 70 newton.
Thing is, the farthest you are from Betz, the less power you produce and also the less drag. Right now we are really cloth from Betz. Maybe rod is not that cloth. Thus he has less drag… Rod ?
Another difference, kiwee…
and on
Yes à little more than 1 m2.
Regarding lifter surface area, as soon as you have consistent wind, kiwee can operate with a 2m2 pilot kite. If the wind is weaker, we need a 4 m2. That is why we choose 4 m2 pilot.
60 degree is not a really high value in consistent winds, more of a common one.
210W is the propeller value. You have to had right angle efficiency and belt transmission efficiency in the calculus if you want to look at power production. For flight angle concern, only propeller charact…
I have not more but the data above are enough to extrapolate in crosswind conditions if a device with efficient enough rope drive transmission is built.