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Old 03-12-2009, 08:06 PM   #89 (permalink)
aerohead
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ideal

Quote:
Originally Posted by hummingbird View Post
I think the ideal shape is neither the forward teardrop nor the reverse one. The objective here is to avoid a detached flow- the forward teardrop pushes a sizable wall of air, the reverse one allows turbulence to form at the end face, increasing drag.

The Ideal shape would be a combined teardrop with the front end formed by a reverse teardrop tail and the back end formed by a normal teardrop tail. The intermediate section can be tubular shape that then reaps benefit of a parting already taken place - something like the bullet trains of Shinkansen Japan or TGV France.
The "ideal" teardrop has the lowest drag for subsonic flow.If you lengthen the nose forward, the drag goes up do to increased skin friction.Anything you do to alter the "ideal" teardrop increases it's drag.That's why they refer to it as "ideal".
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