Hi All,
A while back (say 6 weeks) I put a set of the Falcon mach 5 blades on my treadmill motor mill. I have some observations and I am wondering if they make any sense.
First, some specs: The Falcons: 5 blades, 62" swept area. My home made blades: 46" swept area, 3 blades, NACA airfoil maybe 2512, I'd have to check. I have good data logging for amps/watts output, but my wind speed is currently screwed up. So I don't have a complete set of data to work from, just my observations.
Firstly, the Falcon blades spend a LOT more time spinning than my DIY blades. However, it doesn't seem to spend that much more time actually making electricity. And the peak output seems less. With my DIY blades I have seen around 150 watts, but the most I have seen with the Falcons is about 100 watts.
Of course, I am not comparing apples to apples. I don't know the wind speed was when my DIY blades hit 150 watts, but I'm pretty sure I've hit the same wind speed at some point. But it seems like when unloaded the Falcons get it spinning in lower winds but then stall or something when the RPM's get up enough to start loading the mill. Does this make sense?
Jonathan