I've never seen the actual 2.37 ratio streamline body of revolution referred to published.
If you go further back to Sighard Hoerner's 1951 edition of 'AERODYNAMIC DRAG', he reports the drag minimum @ 2.1:1. however, later in the book he reports that you wouldn't want to actually use it, and he doesn't provide a context.
These streamline bodies of revolution were originally intended for airship bodies.
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When you study airships, you discover that, due to their enormous frontal areas, and wetted surface areas, that when their enormous turbulent boundary layers slough off their aft-bodies, the free-stream passes over the traveling TBL, attached to the tail, as if it's a phantom surface, actually modifying the 'apparent/ effective' fineness ratio.
This wouldn't happen on a passenger car. You could calculate the thickness of the TBL on the motorhome and think about it.
Another thing about airships is that, air sickness is a big issue for crew and passengers. Longer, higher drag envelopes provide a better 'ride.'
In military applications, the longer form provides a more stable weapons platform, especially with bombing.
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Elliptical bodies have the same Cd/per fineness ratio as streamline bodies of revolution.
If you can get access to Wolf H. Hucho's 2nd-Edition book, on page 200, Figure 4.119, you'll see the drag minimum occurring @ 2.5: fineness ratio.
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On page 61 of the same book, Table 2.1, 3rd image from the bottom, you'll see a 'Streamlined body l/D = 2.5:1, @ Cd 0.04.
This body's aft-body does not exceed a declination angle which exceeds 22-degrees, W. A. Mair's minimum for attached flow.
In ground proximity, the body in ground reflection would be Cd 0.08. Around Cd 0.13 with wheels. This is what I used for one of the 'templates.'
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I suspect that, anyone with AUTOCAD, could import a scan on Huchos' 2.5:1 body ( it's actually Hoerner's ) and 'shrink' it with the software, producing something close to a mathematically-correct 2.37:1 body. It would be way out ahead of nothing.
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I'm a scaredy-cat when it comes to other people's time and finances when it comes to fabricating.
I've shied away from any contour which exceeds Mair's 22-degree threshold.
Some production contours do exceed 22-degrees. The ' Champrius' is an example. The 2008 Prius conforms to no known contour, however, if you follow a pathway, halfway through the rear spoiler, then it's an exact match for Wolfgang Klemperer's, 1922, Cd 0.15 streamline half-body.
The Prius aft-body constitutes 40.5% of total body length.
Without the spoiler, the rear separation point is @ a 16.5-degree angle to the horizon.
With the spoiler, it's relaxed to 13.5-degrees.
Halfway through the 3.5' spoiler extension, it's right on Klemperer's contour.
In order to reach Klemperer's 'long-tail' body, one would have to elongate the Prius by 2287.25mm ( 90" ).
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Perhaps someone with AUTOCAD can step up, and do the image morphing.
I'd like to see it myself.
