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Unread 06-02-2009, 19:05
jwkelly jwkelly is offline
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Re: Team 665 Fan/s and More

Quote:
Originally Posted by Tom Line View Post
Back of the napkin tells me that if you're putting out a uniform 28 mph across a 32 inch fan, you'll get around 340 lbf out of it. Anyone want to check my numbers? I guessed on some of my constants - been a while since I cared about air density

If my numbers are right, conservatively you may get 150 pounds of push out of it. Not too shabby!
I'd have to say your estimate is quite generous. We have run a fan test on a 28 inch prop with it directly connected to a CIM motor (1:1). Xoar 28x10 prop gives us approximately 8lb static thrust, whilst a 28x12 gives approx 7lb of static thrust.
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