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Old 01-25-2013, 09:04 PM   #437 (permalink)
Tesla
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Join Date: Feb 2012
Location: Australia
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Quote:
Originally Posted by hotrodfeguy View Post
ok I want to bounce a idea off you areo experts. What if one was to make a scaled down wind tunnel out of a used fish tank(or equalvalant plexi) and take the ends off. Place small fan on one end. Use tufts and or smoke with small coffee straws to highlight flow patterns? By use of a air pump, for smoke output? This way we could rotate car at angles(5*,10* ect) to see how side wind would effect things. Cause when you drive when it's snowing out you can see how the cross wind changes the angle the wind comes at the car. Instead of coming right at the front it comes in at a angle sometimes up to 30*. Questions I have would be:

1) whats the right angle with cross wind?
2) maybe flat on opposite side is better if you were in a all out MPG race with cross wind from one side
3) Maybe a round bubble/bomber butt works at the end?

All crazy ideas I was thinking sorry if these offend.
Firstly, Crazy Ideas is otherwise known as thinking outside of the square, 99% are crazy, but 1% are absolute Gem's, so keep em coming.

As for the wind tunnel idea, may be fun, but as I understand there is a whole lot of scaling issues, tunnel dimensions, vehicle scale, airspeed, laminar airflow etc. and even with full size facilities, there is still a lot of trial and error, things work in tunnel testing, but fail dismally on the road.

From my readings for best all round performance, a bluntish rounded front, generous radius all round, no sharp edges and a tapering rear, not exceeding 22°, if not doing full tail, then truncated with a small lip at rear to promote clear seperation.
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