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Old 05-19-2013, 01:29 PM   #21 (permalink)
kach22i
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Quote:
Originally Posted by ChazInMT View Post
If you dive down to 22° when you should be at only 8°. it will not be a good thing.
To clarify even further, of course the transition should be gradual.

Taking the images posted and estimating with an adjustable triangle on my computer screen, we can see that the angles of inclination do increase.

Automobile 2 - Odds And Ends Photos by kach22i | Photobucket


I think there is a matter of scaling to consider which we should not leave out.

Say for instance we mount a 1/6 scale model of the car to the roof of the full sized car. The Cd of the model should be close to that of the full sized car without the roof attachment, right?

The frontal areas of the full sized car and model will be dramatically different, but the Cd's should be similar.

Now for argument's sake, graph on a "known to work" roof transition without regard to scale.

Automobile 2 - Odds And Ends Photos by kach22i | Photobucket


My hypothesis here is that when thinking about "scale", be it for a more aerodynamic mirror, roof luggage, trailer or an entire car body, we may have far for liberties at hand than normally accepted following the template at the standard scale.

What the Geo Metro and Pontiac Firefly roof garnishments prove to my eyes, is that re-scaling principals are already being applied, although nobody is calling them that just yet.

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