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Old 03-12-2016, 01:44 PM   #11 (permalink)
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avoiding large negative pressures

Originally Posted by kach22i View Post
Nice thread, sort of wish there were extreme examples such as the Aero-Template car and a Pick-Up Truck for comparison.

Is it accurate or ignorant to say/think that avoiding large negative pressures will in turn avoid producing large positive pressures?

That is to say, if you never accelerate the air to begin with, it will not have to slow down later to equalize the mass air flow (correct term?).

The so-called perfect shape would have quite a bit of lift, perhaps we should turn this thing upside down?

Nice little paper on down-force without wings:
*avoiding large negative pressures wouldn't be the issue.We'd have to have zero shape (a flat car).
*3-D streamline shapes do not produce lift as in a 2-D airfoil.The nose is held down by the favorable pressure gradient in the forebody.The tail is held down by the near-fully recovered static pressure of the separation-free aft-body.
(the T-100 showed essentially zero lift at 135-mph according to DARKO).The T-100 is also almost 50-50 weight distribution on the axles.
Here you can see the negative-lift positive pressure (blue) cancelling out the positive-lift negative pressure (yellow) acting on the 3-D body

*If we invert the streamline body,we lose attachment over the top (lift) and we force the total pressure under the vehicle (more lift).
*The streamline half-body remains very low drag.If you have dynamic stability issues,it's due to a conflict between center of pressure and center of gravity.

Photobucket album:

Last edited by aerohead; 03-12-2016 at 01:46 PM.. Reason: add data
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