Quote:
Originally Posted by Cd
I remember reading in a magazine decades ago, when a "GM Engineer " explained that the cD was nearly identical for both the 3rd generation Camaro and Firebird, despite the Camaro having bucket headlights.
( CarCraft magazine )
He explained that the air pooled and created a swirling pocket of air that oncoming air skipped around.
So the drag that was being created by the turbulence in the headlight buckets was "cancelled out" by the airflow skipping over the turbulent air.
Even back then as a teen, that didn't make sense to me.
Any oncoming air would BECOME turbulent air as it met the "swirling pocket of air "and it would create drag.
Also, all air flowing over a turbulent body eventually becomes stagnant again farther downstream anyway.
I'm guessing the amount of drag created is a result of how quickly the airflow goes back to it's stagnant state.
It doesn't cancel out the drag that was created.
But I sure would like to be wrong.
Anybody have any comments ?
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One reason for bringing the smoke flow images back was so, everyone could 'see' the Lanchester/Prandtl surfaces of discontinuity out ahead of all the cars.
This is exactly the evidence that laminar flow will travel over stagnation bubbles, and that 'buckets' aren't necessarily 'parachutes.'
Allowing for anthropomorphism, the air is already trying to figure out how to get around the car, long before it actually 'arrives.'