Teratornis ( talk) 03:24, 5 January 2009 (UTC) Small scale (sub-25kW range) often have rotor speeds in the hundreds of RPMs. As far as rotor RPM goes, it's a function of rotor diameter - bigger rotors turn more slowly (although the tip speed ratios are similar due to the longer blades). NASA quickly gave up on downwind rotors, as did the rest of the industry.
Each time a blade passed through the tower wind shadow, the sudden drop and then immediate rise in wind force on the blade was like dropping an elephant on it.
I also just spotted "The blades rotate at 10-22 revolutions per minute", when myself and my friends measured one at 30rpm last weekend, so the two citations must be wrong (or the turbines we saw were out of control) 86.44.200.132 ( talk) 18:09, 4 September 2008 (UTC) Is it even possible to buy a commercial-scale wind turbine with a downwind rotor? NASA discovered the downwind blade fatigue problem with its early MOD series test turbines. Also, turbulence is not the only factor causing fatigue loading in turbines, the rotation of the blades and fluctuation in mean wind speeds (on which turbulence is superimposed) are also contributors.Īnything can fail if subjected to a high enough level of fatigue loading for long enough, but I don't see Yuri Geller's trick listed as a disadvantage on the spoon page. With a failure mechanism of something as expensive as a wind turine, if the lay-man knows about it, then it doesn't happen anymore. I don't like the line "Downwind variants suffer from fatigue and structural failure caused by turbulence." If they all suffer from fatigue and structural failure then what engineer would be dumb enough to choose them? Choosing the right materials and paying attention to vibration modelling will solve that problem at the cost of something else.