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Old 11-13-2010, 04:00 PM   #99 (permalink)
aerohead
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sharper

Quote:
Originally Posted by TestDrive View Post
Does it necessarily follow that putting a sharper nose on a streamlined half-body will increase Cd?
The argument is that it will not lower it,the additional surface drag associated with the added structure necessary to extend the nose forward to a point,by default,increases the profile drag,so there's no point doing it.
Once to 250 mph ( with cars ),there would be an advantage to the ogival nose.
If you'll look at any wind tunnel photo of a car 'in smoke' you'll notice that the streamlines are already deforming well ahead of the actual body of the car as they undergo what Ludwig Prandtl called a line of discontinuity,avoiding sharp turns,as if the nose was already 'pointed.'
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