Well, maybe we are talking past each other? I am wondering how any vehicle can actually be built and be usable on the road with a Cd less that 0.1?
No reasonably practical road vehicle has ever been built with less than a Cd of 0.1 except the early Bionic/Boxfish model. The next lowest that we know of is the Aptera "Zen" at 0.11 with it's nearly pure Morelli and wheels on struts.
How can a rolling, practical car be built to beat lower this drag?
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What I mean is, while the blue clay model may have had a Cd of 0.095, I disbelieve that its basic body shape would make for lower drag than that of the other cars I mentioned. A direct translation from blue clay model to real, drivable car (which M-B didn't do) would add considerable drag and would give it an impressive but not unprecedented Cd, and a rather ordinary CdA.
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Matt, other than some additional ground clearance to clear normal road bumps and an air intake to cool the passengers, the design would seem to be able to at least match the Aptera "Zen", in my opinion. They do say that the shape is totally counterintuitive -- nature "figured out" something that we have not yet. The very low stagnate point and the wedged hood and hard chined front fenders are probably key. They match the function of that funky nose on the real fish, and they "work with" the ground surface.
I plan on integrating these into my CarBŒN design, as well as the more curved sides and roof; with the little "flip" at the back. Mercedes left most of these off of the final Bionic car, and they added a diesel which needs lots of cooling; and so their Cd slipped quite a bit. An EV has a minute need for cooling, so I think that much of the Cd could be "kept" in a real car.
The shape is certainly practical for lots of seats.
It's ironic that Jim is saying we should be able to build a real car with 0.06-0.08 Cd, and Matt is saying that 0.1-0.11 is way too much to expect...
We all want to have that ultimate low drag, low weight, uber-high efficiency car, I think, and I think that all of us are willing to accept what the best design requires within reason. (No maglev systems!) I think a monolithic design like the Boxfish model has the best chance of hitting these needs. I think that with a shape with outboard wheels has it's own more complicated challenges.