Meet the Schloerwagen! (and a question for aeroheads)
 

http://24.media.tumblr.com/13bfb1b84...gxsbo1_500.jpg

http://www.retronaut.com/wp-content/...-4-620x413.jpg

i'm sure some of you guys are familiar with this aero beauty! the "Pillbug Car" was built in 1939, based off of a mercedes-benz 170H.

i wonder why they didn't go for a more conicular, graduated nose. perhaps it would've been too long? actually, this brings a question to my mind... would it be better, aerodynamically, for a car to have EITHER a gradual front end-nose cone type setup OR one with a boat tail on the rear end? (assuming that both would be built to maximum aerodynamic potential?)

in short, does the front or rear end of a vehicle hold more potential, in aero regards?

also check out more pics of the Schloerwagen at the following link: :)
The Schloerwagen or "Pillbug" car Retronaut | Retronaut - See the past like you wouldn't believe.

Yup, we have seen it for sure! A search here on EM for Schlörwagen:

http://ecomodder.com/forum/showthrea...30s-325-2.html

http://ecomodder.com/forum/showthrea...30s-325-6.html

http://ecomodder.com/forum/showthrea...tml#post252228

http://ecomodder.com/forum/showthrea...6-a-13198.html

http://ecomodder.com/forum/showthrea...tml#post286943

A blunt nose like the Schlörwagen is better for low drag than a pointier nose. This too has been discussed many times here on EM.

I don't agree... i mean, the fastest cars (salt lake turbine) and fast planes uses cone noses... why you say that is better like that?

Dammit, not this again. :rolleyes:

Above 250MPH is different than "normal" speeds - aerodynamic "rules" are different above or below ~250MPH.

nose
 

*There's a couple schools of thought:
1) Do all the streamlining at the front and minimize the aft-body.Since 1974 I've only run across two studies where emphasis was concentrated at the nose.
*Eiffel studied what I call the Parisian ice cream cone (simply because it looks like one),with a convex hemispherical nose integrated directly into a conical tail,angled at 20-degrees to the longitudinal centerline.
*Dropping the cone tail first off his Tower,he measured Cd 0.18.
*Dropping it ice cream first,it recorded Cd 0.09.
*Baron Reinhard Koenig-Fachsenfeld,in the Technical University of Stuttgart's aeronautical wind tunnel studied a streamline body of revolution of L/D= 6:1.
*he ran it head-first and tail first.
*Tail-first it recorded Cd 0.55.
*Head-first it recorded Cd 0.45.
*As an automobile,running tail-first (or a reverse-Template),with wheels,it would have a drag minimum of Cd 0.142 with 'best' L/D ratio.
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So it's possible to make a car of Cd 0.142 with most of the streamlining out front.The catch is that any windshield sloped to respect the tail-first contour would be slanted back so steeply that you'd never be able to see out of it.Something the HONDA HAWK team ran into at Bonneville during their LSR attempt.
The 1978 Volkswagen ARVW canopy delivered carnival 'fun-house' optical qualities for one auto journalist who drove it at VW's proving grounds.
And nothing in the published literature suggests that you could take any liberties at all with the nose.It would HAVE to be constructed exactly like a reverse-'Template'.
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2) Conventional wisdom for sub-sonic bluff-body road vehicle aerodynamic streamlining is to have a convex-hemispherical nose-based forebody,combined with a long,tapering teardrop tail aft-body.
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Wolf Heinrich Hucho was directly involved in the development of VW's Vanagon.In his book he has a drag table illustrating how little leading edge radius it took to achieve the lowest drag.Once they chiseled the clay a bit,no amount of further rounding produced any lower Cd.This was for zero-yaw of course.Later in his book he shows the 'bulbous' nose as the low drag champ for crosswinds,which is where we do most of our driving.
*The piece de resistance is in another table in which the entire drag of the nose constitutes a whopping 5.88% of the vehicles overall drag.Skin friction is 22%.The rest is aft-body drag.Over 72%.
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This is an extremely long way of saying that your energies might be better spent working on the back of the car.;)

fastest
 

You've provided the context under which the cone would have the advantage.
At the trans-sonic and supersonic velocities of the LSR vehicles,the shockwaves generated on a 'bulbous' nose would block momentum interchange into the boundary layer,triggering separation right there,with no re-attachment.Which could be catastrophic.The 'ogival',or pointy nose is designed to squash the shockwaves,allowing clean flow to the rear,where fins can keep the CP behind the CG.
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For daily commuting though,as others have mentioned,the pilbug's nose is actually ideal.Koenig-Fachsenfeld has a photo of it in the Stuttgart wind tunnel and the smoke flow over it could not be improved upon.It does have a robust stagnation area but that's great for the cooling system and cabin ventilation.
With the Ludwig Prandtl' flow lines of discontinuity the streamline filaments are moving as if the nose projected to a point anyway.
It's 'weird' but it's the way of the world.:p
PS if you'll do a GOOGLE Image search with Windkanal,you'll eventually get to a color photo of the Schl'o'rwagen model under smoke and green light in the wind tunnel.It's pretty sweet!

wind tunnel pic
 

Thanks Frank! That be de animal!

thanks aerohead! this is all great info