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Old 09-04-2020, 05:27 PM   #31 (permalink)
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Originally Posted by aerohead View Post
Online, there's an image of a Schl'o'wagen model being tested under green light, with smoke introduced into the boundary layer if memory serves me. The smoke does not entirely follow the roof contour. Other shapes with a more conservative roofline have measured Cd 0.13.
I'm fairly certain the picture you are referring to was taken from a 90 second video in the link I posted. I'm almost certain I remember seeing a much longer video that contains more about the subject but I can't find it. As I previously stated, I'm fascinated with the discussion but I was away from the site for a while and wasn't aware if the information on the page had been discussed or not.

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Old 09-04-2020, 05:41 PM   #32 (permalink)
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With respect, this is likely to just send us back to the BS from which the original garbage descended.

Note: I am not saying that these cars are of no interest, or they they were backward at the time. In fact I am a great fan of them.

But....

The Cd values recorded at the time for these cars are highly unreliable, as has been demonstrated when full-size cars of the past have been tested in modern wind tunnels.

...and...

The designers of the time cared nothing about lift, and so basically all the shapes shown are of such high lift they would never be released by any responsible car company today.

...and...

In general, the designers were not aware of the drag resulting from trailing vortices, and so attached flow was often seen as an end in itself.

More than anything else, these factors explain why no current cars look anything like these cars. For exactly the same reasons, it also explains why using some sort of standardised approach (a template) based on these ideas is usually a pretty bad idea, and using such a template as some sort of model for changing an existing car is an even worse idea.
I almost didn't bother posting the link in fear of beating a decayed horse, but as you said, those old cars are very interesting! I fully admit to only half following the scientific arguments, so I thought the videos of a close follower of the template might help those with the knowledge discuss in a manner a dummy like me can follow.

I also can't remember where I came across the information, but I'm positive that car was highly unstable at highish speeds, as well as being quite huge.
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Old 09-04-2020, 07:14 PM   #33 (permalink)
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I also can't remember where I came across the information....
It was in that link you posted at Permalink #12.
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Old 09-05-2020, 10:16 AM   #34 (permalink)
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:facepalm: I've violated the long established axiom of opening my mouth and removing doubt of my foolishness.
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Old 09-05-2020, 12:32 PM   #35 (permalink)
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OTOH, someone looked at the link you provided.
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Old 09-06-2020, 07:16 PM   #36 (permalink)
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:facepalm: I've violated the long established axiom of opening my mouth and removing doubt of my foolishness.
Don't worry. That axiom does not stop any of us on this site from doing likewise.

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