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Old 11-30-2014, 11:05 AM   #621 (permalink)
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Some CFD flow images of the car, and some of a standard car without the aero modifications :






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Old 12-01-2014, 12:53 PM   #622 (permalink)
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What got me thinking about the boattail was whenever I drove down a leaf covered road in the fall in the OEM shaped car, I would see leaves continually popping up behind the rear glass in the rear view mirror as I drove down the road. This told me there was a massive recirculating eddy being generated behind the car that was picking leaves off the road and lifting them to the height of the car.
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Old 12-01-2014, 01:07 PM   #623 (permalink)
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Got a leaf stuck under my rear wiper on Saturday, so I know what you mean!

The CFD is great! It looks like there is some turbulence underneath the rear of the boat tail. Will you be addressing this, or is it not a big concern due to your already ridiculously low fuel consumption?
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Old 12-02-2014, 01:07 PM   #624 (permalink)
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I'll just have to live with that turbulence since I occasionally use a driveway with a sharp approach angle and can't have the boattail from dragging the ground when I turn into it.
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Old 12-02-2014, 01:20 PM   #625 (permalink)
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Ah, but I figure you've got the ingenuity to design a collapsible bottom! Maybe like those semi truck boat tails.

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Old 12-02-2014, 05:38 PM   #626 (permalink)
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I've always thought that the car could just have a hinged coroplast skid plate that hangs down with a radiused edge at the rear.
As the car backs out of the driveway, the plate would make contact with the ground and be pushed upward.
When out of the driveway, the plate would lower with the force of gravity and increasing air pressure would provide enough lift to raise it to the perfect angle that the airflow finds optimal.
Two cables would hold it on.

I should add that the CFD images may not be totally accurate, and this entirely due to my lack of understanding of how to use the program.
Sometimes artifacts appeared, and the tests contradicted themselves.

I fully encourage others here that are CFD pros to run professional level testing on the car.
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Old 12-02-2014, 05:44 PM   #627 (permalink)
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Quote:
hinged coroplast skid plate
Ahahahaha. Ha ha. Hehehe. He.

How about a hinged, spring-loaded diverter with skegs that have skateboard wheels in the tips?

Last edited by freebeard; 12-02-2014 at 07:09 PM..
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Old 12-02-2014, 06:00 PM   #628 (permalink)
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Why wouldn't Coroplast work ?
It would be light enough that the airflow would actually lift it to the optimal angle.
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Old 12-02-2014, 06:04 PM   #629 (permalink)
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how about

Quote:
Originally Posted by freebeard View Post
Ahahahaha. Ha ha. Hehehe. He.

How about a hinged, spring-loaded diverter with skegs that have skateboard wheels in the tips?
Could happen!
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Old 12-02-2014, 07:08 PM   #630 (permalink)
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I'm sorry, Cd. If you'd said 'coroplast diverter', I could agree.

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