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Old 11-28-2022, 10:10 AM   #18 (permalink)
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IONIQ @ 'template'= 'lower'?

Originally Posted by Cd View Post
I notice they had to stretch it to fit the roofline of the Benz, which is closer to the template.

This is yet another car that puzzles me. It has too "fast" of a drop in the rear glass, yet gets a .21 cD.
I would have thrown up my hands and given up on the idea of templates and boat-tails, except for the fact that the Mercedes Concept IAA dropped it's cD lowest with the addition of a short tail section.

So, Aerohead - if this design had just left off that shelf spoiler, and instead followed the template curve, would the cD have been lower ?
I believe so.
The Ioniq 6 ( pseudo-Jaray ), @ a fineness ratio of approx. 3.121349, and Cd 0.21 IS more efficient than some other Cd 0.21 cars.
However, if you consider the M-B Bionic Boxfish ( kammback ), which is 12.7% more 'bluff' yet Cd 0.19, or the Coventry University-modified Audi A2 ( kammback ) , which is 16.9% more bluff, and Cd 0.204, then the Ioniq doesn't shine so bright.
If you agree that the Ioniq 6 shares DNA with the 1968 PORSCHE 911 ( pseudo-Jaray / pseudo- Lange-car ), and the 911 had serious lift and drag issues, and the proper solution was a 'kammback', then it's not a reach of the imagination that a 'kammback' on the Hyundai would have improved things.
Since 1974, I've seen no evidence that a 'shape' exists, which can out-perform the 1930s 'kammback.'
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Last edited by aerohead; 11-28-2022 at 11:56 AM.. Reason: typo
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