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Old 08-09-2009, 09:40 PM   #34 (permalink)
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I thought I would post these which I made last year. I can't remember the values I used but I have not been able to reproduce them since.

I notice now that the angle of the kamm on the second video is just a touch too steep as there is some separation there. Who knows how accurate these are. I have been scouring aerohead's images for the best angle for the afterbody. It seems to range from 10 to 22 degrees. I measured mine again and got 17 degrees on the actual kamm. The video is 22 degrees to the mid point and goes steeper after. I will have to do more tuft testing to be sure on the actual Kamm and I may change the angle depending on how that pans out. My tufting seemed good at 17 but I only got up to about 45 mph.

I updated the annotations to reflect my current understanding of the theory (corrections and clarifications welcome)

Vortex generators are old tech. My new and improved vortex alternators are unstoppable.

"Itís easy to explain how rockets work but explaining how a wing works takes a rocket scientist."
-Philippe Spalart

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