Re:The Mesmerizing Math of a Wind Turbine on Fire
by jacquesm on Saturday August 06, 2016 @04:28AM
(#12237510)
You are spot on, that is more confirmation for my suspicion of overvoltage. The power drives the windmill, so the machine is rotating faster than the wind it generates due to slippage.
Normally it would be the other way around, the wind would pass through the turbine faster than it could move (Betz' law, in both cases but for the opposite reason, just like it is impossible to extract all the power in the wind due the air then having to 'pool' around the windmill you can't transfer power with 100% efficiency from the rotor to the air either, you'd create such overpressure behind the windmill that some of that air would have to move back to the front of the rotor. This stuff is all not-so-intuitive and the video is actually (accidentally) a really nice illustration of Betz' law at work.)
Normally it would be the other way around, the wind would pass through the turbine faster than it could move (Betz' law, in both cases but for the opposite reason, just like it is impossible to extract all the power in the wind due the air then having to 'pool' around the windmill you can't transfer power with 100% efficiency from the rotor to the air either, you'd create such overpressure behind the windmill that some of that air would have to move back to the front of the rotor. This stuff is all not-so-intuitive and the video is actually (accidentally) a really nice illustration of Betz' law at work.)