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Old 11-03-2011, 07:50 PM   #50 (permalink)
aerohead
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Quote:
Originally Posted by jimepting View Post
I'm seeing more and more vehicles which "appear" to have roof taper very close to template. Perhaps more modern windtunnel testing is showing that for a given length, better aero is achieved by keeping template taper and increasing transom area wake. I've always been a bit suspicious that these folks were just maximizing internal room.

Honda pretty clearly put the insight just on the ragged edge, a different approach. Since they were commited to a 2 seater they had options.

The
With the higher CAFE standards they may be choosing some length,and then by doing a good K-form roofline,they get the lowest drag per unit length.
This is exactly what Fachsenfeld and Kamm and Korff advocated.
Kamm and Korff recommended that cars be chopped off at 50% frontal area.
Todays Bugatti Veyron does exactly that.It ends at 49% aft-body which if it also had the plan-taper,would end up at 50% area.
They keep the broad rear to help keep it earthbound at 258-mph.
If we extend out to the full enchilada we get Cd 0.13.
If we streamline the wheels we can go below Cd 0.10.
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