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Old 01-27-2010, 08:00 PM   #14 (permalink)
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Originally Posted by ChazInMT View Post
OK here's a response, with graphics.

I guess it's more of a question,

You state somewhere in here that the wheels of the vehicle should rest on the ground plane.
Yet you say that flow separation occurs at 4 seconds after midnight.

It seems to me that these 2 statements contradict in the sense that air will either remain attached to a given shape until it reaches 4 seconds past midnight (115 beyond stagnation) on a curve (Red), or, you need to overlay a huge wing section onto a given vehicle (Green), and if you fall below this line at any point, you have flow separation, even if it occurs at some point less than 115 (which in this case is on the ground 20 feet behind the truck).

Which one is it? Red or Green? Or am I missing something? (Again, as usual)

(1) Yes,the longitudinal centerline constitutes the ground plane and the vehicle would be scaled to fit with it's wheels on the "ground",and the highest point of the roof aligned with the 12:00 O'clock position.The rest of the roofline is defined by the curve.
(2) The very back of the teardrop is the separation point,so all points ahead of that are in attached flow.
(3) Since all vehicles must have ground clearance,it would be impossible(and unnecessary ) to build a body the full length of the drop,as it would end where intersected by the belly line.
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