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Old 05-20-2017, 02:45 PM   #21 (permalink)
aerohead
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wedge nose

Quote:
Originally Posted by slipknotsv View Post
Mr. aerohead please comment
Scientifically,and from empirical research in wind tunnels,the lowest drag nose,for sub-sonic,incompressible flow,is half of a convex hemisphere,or,'bulbous' nose.
It allows for essentially-ideal,symmetrical, uniform streamline acceleration,directing,over and around the body.with a minimum of surface area (friction),and absence of pressure spikes,with full attachment,and enough camber to set up divergent aft-body flow.
Here it is in 2-D flow

Notice the effect of the aft-body.
Once it reaches supercritical Reynolds number (20-mph with a car),there's full attachment right into the aft-body.(3-D flow)

Here it is underwater

It's perfect!
Here's the origin of the perfect subsonic shape,dating to as early as 1898,with Gustav Eiffel and his famous vertical wind tunnel,Eiffel Tower in Paris.(think ice cream cone)

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Last edited by aerohead; 05-20-2017 at 03:14 PM.. Reason: add image
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