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Old 05-14-2012, 07:35 PM   #9 (permalink)
aerohead
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Quote:
Originally Posted by drmiller100 View Post
airplanes operate at higher speeds then our cars - higher speeds imply different reynolds numbers which means they get to use different degrees of taper.

An example - airplane wings "stall" if you go too slow.
I want to tread lightly here,but according to boundary layer theory,once critical velocity is attained,and the boundary layer is turbulent,all structures will follow the 115-degree rule,regardless as to whether they're a plane,car,or submarine.
If air,or any 'fluid' is attacking a particular curve,of any given radius,if 'zero' is the forward stagnation point,the 'fluid' MUST separate at 115-degrees of rotation beyond the stagnation point.
Example: if an analog wristwatch is moving from right to left,and the air first strikes at the 9:00 position,the air will not be able to remain attached beyond 4-seconds after 12:00.By the way,the angle at the separation point is 22-degrees.
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