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Old 07-30-2013, 04:15 PM   #41 (permalink)
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Dryden

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Originally Posted by ennored View Post
Yeah, half bodies, I didn't type 6 when I first typed a response.

Sure, the air molecules would LIKE to take the easy path. But the air molecule before you already did. Easy path isn't so easy. Air molecules bumping into one another. Energy wasted.



Another thought. A .21 Cd for the shape on the right makes things like the Dryden van (which is shaped like the right shape) seem pretty good at a .25 Cd (approx. - from memory) in the real world. Hmmm....
Cd 0.238 was the value with the stinger in place on the tail.Pretty sweet considering that the Ford Econoline underneath is Cd 0.48!

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Old 08-01-2013, 12:12 AM   #42 (permalink)
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With sharp lower edges,and even running boards on a pickup,it's harder for the high pressure underneath to even telegraph itself up onto the sides of the vehicle.
Whoopsie. I was thinking about getting rid of my running boards.

Morelli? Banana car?
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Old 08-01-2013, 05:21 PM   #43 (permalink)
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running boards

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Whoopsie. I was thinking about getting rid of my running boards.

Morelli? Banana car?
*If you were going to run the pontoon fenders,the running boards could stay,and the fenders could be blended into the body as Breer did with the DeSoto Airflow,for reducing the 'bumps' as Richard Whitcomb of NASA did with his Coke-bottling/Whitcomb-waisting.
*If the fenders are going bye-bye as in your avatar,then that beautiful belly down under probably won't be the liability like on a body-on-frame,deep ladder-type chassis pickup truck,in which case we can lose the boards.
*On the pickup,we're going to have some of the highest pressures in the industry,and the running board will act like a crude wingtip spoiler,preventing the high pressure underneath from spilling up onto the faster,lower pressure body sides and on towards the roof.
*Morelli's banana car is a conundrum.NASA published a mathematical algorithm for the form in the 1940s.They probably never considered it for an automotive body.With Cd 0.05 in ground effect,without wheels its astonishing.0.03 lower than the best half-body!
But when wheels were added,the drag jumped beyond the streamline half-body (Cd 0.161) and when lowered to the road surface doubled in drag essentially,to Cd 0.35.
They had to do a lot of clay modelling around the wheels to finally get it down to Cd 0.201,absolutely great for 1976-78,but already eclipsed by lower drag in the 1920s,1930s.
Where 'caveats' are allowed with the half-bodies,it appears that the NASA/Morelli form cannot tolerate any 'contamination' of the pure form without suffering severe degradation.
I love the car,and Alberto is a real hero.Casting pearls before swine is fraught with long spells of quiet desperation.Paris fashion overpowers average reasoning.Folly.You could write stand-up routines around it.
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Old 08-01-2013, 07:09 PM   #44 (permalink)
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I had to go Searching for what I was talking about. It turns out it was post #34 in this thread.
Quote:
Edit: Well, I can't sleep. the whole body kit could be done in PolyMetal as simple curves. With curved scores in the flat sheet and basically a sector bent into a conic section. I made fender flares for a '62 13-window once that way.
The design is refined down to 6 pieces that fit between the stock finders
  • 2ea rocker panels that have a swage line 4" above the bottom door cut, convex below the line and concave above, 10" deep in total to engulf the lower door hinge
  • 2ea door filler fascia pieces
  • 2ea speed whiskers that replace the front quarter and door chrome trim pieces and fair the turn signal on top of the fender into the top door hinge OR maximally to mimic the Dedge Viper fender scoop


At this point I have basically three distinct Beetle designs
  • The original from '95 as seen in my profile pic, a bullet nosed Kamm-back.
  • The Very Light Volkswagen, which is taking form—slowly—right now as a redwood zeppelin
  • And, the PolyMetal body kit for the stock Beetle.

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