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Old 08-11-2017, 11:08 AM   #11 (permalink)
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A kammback - which is basically a truncated boat tail - is probably most appropriate, as freebeard is suggesting.

Aerodynamics is a bit of a dark art, as far as I can tell. Although there are plenty of design guidelines that work reliably, you'll find that intuition often doesn't work with complex shapes. You can be pretty certain that, although the tiny kamm on the back may poke out of the profile, it almost certainly lowers drag overall, or Toyota wouldn't have put it there. The RAV is a very complicated shape, and the kamm could be correcting for something like the mirrors, or perhaps the windshield angle is too steep for there to be attached flow along the front of the roof, but it reattaches at the rear. Without doing extensive testing, you just can't know.

It's not a technical article, but I was amused by this recent post on Jalopnik:

deadspin-quote-carrot-aligned-w-bgr-2<\/title><path d="M10,3.5l3-3,3,3Z" style="fill:%23fff;stroke:%23fff"/><path d="M0,3.5H10l3-3,3,3H26" style="fill:none;stroke:%231b3a4d"/><\/svg>')}.f_branding_on.blog-group-deadspin .editor-inner.post-content .pu


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Old 08-11-2017, 04:49 PM   #12 (permalink)
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I saw the article, I read every thing that Torchinsky writes.

But I allowed Javascript for kinja.com and kinja-static.com and I still couldn't see the poll. I didn't know which of the other 16 scripts powers the poll, so I moved on.

Yay for the Type II!
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Old 08-12-2017, 01:33 PM   #13 (permalink)
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length

yes,the long length has always been the bugaboo of truly low-drag vehicles.It's why Kamm and Fachsenfeld spent so much time researching cost/benefit for varying lengths.
Kamm/Fachsenfeld settled for a car body which followed a streamlined pathway,then was chopped off at a point where the new wake area was 50% of the car's frontal area.
The Fachsenfeld went one better,creating an inflatable boat tail which would only deploy on the highway,far from parking garages,traffic,etc..
With the stinger,my truck will be 311.6-inches in length.
With only the boat-tail,269.6".
The longest vehicle on the road today is a 2012 Dodge RAM Laramie Longhorn DRW pickup,at 259.4".
At 30-mph a tail won't do you much good.I don't know what to recommend.
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Old 08-12-2017, 01:45 PM   #14 (permalink)
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E-Type Jag

Quote:
Originally Posted by Ecky View Post
A kammback - which is basically a truncated boat tail - is probably most appropriate, as freebeard is suggesting.

Aerodynamics is a bit of a dark art, as far as I can tell. Although there are plenty of design guidelines that work reliably, you'll find that intuition often doesn't work with complex shapes. You can be pretty certain that, although the tiny kamm on the back may poke out of the profile, it almost certainly lowers drag overall, or Toyota wouldn't have put it there. The RAV is a very complicated shape, and the kamm could be correcting for something like the mirrors, or perhaps the windshield angle is too steep for there to be attached flow along the front of the roof, but it reattaches at the rear. Without doing extensive testing, you just can't know.

It's not a technical article, but I was amused by this recent post on Jalopnik:

deadspin-quote-carrot-aligned-w-bgr-2<\/title><path d="M10,3.5l3-3,3,3Z" style="fill:%23fff;stroke:%23fff"/><path d="M0,3.5H10l3-3,3,3H26" style="fill:none;stroke:%231b3a4d"/><\/svg>')}.f_branding_on.blog-group-deadspin .editor-inner.post-content .pu

Ralph Gilles,who was responsible for the design of the SRT Viper refers to the E-Type shape as 'extreme cab-rearward'.
They can't produce low drag but stylists love 'em.
In the day,The E-type would have been low in drag,and with only 16-plus square-feet frontal area,the drag index wold be quite favorable.
Consider an MG TC,with Cd 0.75!
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Old 08-12-2017, 04:04 PM   #15 (permalink)
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Here's an example of a 'cab-forward XKE', with a Cd good for it's day or any other. A contemporary of the MG-TC as I recall.

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