Phil Knox Darko Wind Tunnel video

[freebeard]

...at most this good. Or better.

Something like that.

[aerohead]

Originally Posted by sendler

So a full scale electric car could be expected to do at most this good. Or better.

It's a great question and I can't give you a definitive answer.
What I could mention is that:
*There might have been a sweet spot with rake/inclination that I couldn't test for.
*The bottom of the wheel fairings were completely open,since,I didn't know how we were going to attach the model to the load cells before I got to DARKO.Once the model was strapped down there wasn't much we could do to seal these areas,and time was very critical,as we went over budget as it was.
*I left an area truncated,large enough for taillights and a license plate,which might be 'handled' differently.I don't know.
*The Cambridge University CUER,of 2013 had the knife-edges in the back,for Cd 0.11.
*The 2018 University of Michigan solar racer is dropped into the weeds,for an advertised Cd below 0.10 (they won't reveal the number yet).
*Hucho says this wheel 'integration' might allow as low as Cd 0.08.
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All we know so far,is that Paul Jaray was correct in 1922,as far as an in-the-bag low drag form.And because of the wheel fairings we can beat his shape a bit.
If we add mirrors we'll see a drag rise,but with cleaner wheel fairings,it might net out at the same Cd 0.12.
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For 2020,I'm gonna try 8-feet of tail and a fake single wheel to simulate BamZipPow's Dark Arrow one-wheel trailer.If it works out,we my be able to demonstrate a gap-filled, one-wheeled trailer,which could carry a second battery pack,with low enough aero to,by itself, extend range by 25%.(for instance,387-mile range for the Tesla S P100 like I drove up in Kansas City in March)
775-mile range for a P100 pulling the trailer.That would be interesting!
That's all I can think of.

[freebeard]

We need to talk about all that sanding and finish work you put into Baby.

Here's a design I did for an aeroform for the Arcimoto FUV, to show a method of formless construction.



No angle is greater than maybe 5°, and those are at the nose and tail. The seams at the profile, 'equator' and bulkhead could be backed with tubing or the edge of a plate.

All it needs for your application is a truncation in front and a squircular transformation.