What woud be the ,optimum car nose shape given what is known about air curtains, undertrays, etc?e
 

Starting with a clean piece of paper and given what is known about air curtains, undertrays, nose stagnation and compression of airflow, etc., and given conventional car shape, what would such a face look like?

In other words, if Hucho, Julian Edgar, NASA nerds, and the best minds of Porsche, BMW, Audi, Toyota, and Ferarri all got together with the best minds on this website, what would they come up with, vis most efficient car nose shape?

https://ecomodder.com/forum/member-f...07-7-35-02.png

It depends on the design brief/use case. Things like lighting, cooling,etc. The big one is driver sight-lines. A flat windshield at 90 degrees to sight-line is best, sloped and curved windshields are subject to refraction and glare.

The example uses flat faceted panes, while the rest of the body can be compound curved. The two forward facing hexagons could be flattened, enabling a Luigi Colani spinning windshield wiper. The front wheels are held back where leading and trailing spats are possible. The overall form is your nominal solar racer inflated for interior volume.

Probably a Halibut shape....

Boxfish

https://ecomodder.com/forum/member-f...5089-nx8ig.jpg

I guess it's a fair question.

Design by committee is how the camel got designed though.

most efficient
 

It dates to World War-I.
It was on a British warplane, with forward machine gun position, and pusher-prop. They hadn't figured out yet, how to synchronize shooting bullets through the rotating propeller.
Anyway, Hucho called it both 'Optimum' and 'Ideal'. The 1922 Jaray and Klemperer basic bodies use it, Walter Lay used it in 1933, Kamm did research with it in 1935, Schl'o'rwagen 1938, Lancia Aprilla by Pininfarina 1944, 1978 Hucho basic body, SMART Fortwo, Aston Martin Cygnet, many many others have used it.
If you're not going to skirt the front wheels, then the air curtains are a palliative to the drag created by the open wheel arches.

R. Buckminster Fuller got the number of wheels right.

http://www.washedashore.com/projects...ar_vs_ford.jpg
http://www.washedashore.com/projects...dworld/e51.jpg
www.washedashore.com/projects/dymax/pictures.html
Dymaxion #3 posed with Fuller's personal aircraft, a Republic Seabee. An interesting airframe that inspired Sandy Munro's aircraft design.

http://www.bubblemania.fr/wp-content...ON-CAR0045.jpg
http://www.bubblemania.fr/dymaxion-c...ner-americain/

Lots of good pix there. The Fuller/Isamu Noguchi model:

http://www.dailyicon.net/magazine/wp...3dailyicon.jpg
http://www.dailyicon.net/2009/02/dym...isamu-noguchi/

Putting it bluntly: nose shape has relationships with width, height and maximum vehicle length. Naca found that a 2" radius nose on their laminar semi symmetrical series was required for the laminar flow but mostly for stall conditions. As illustrated by the F104 wing, things get squirrelly really fast in a sharp edge wing at stall. The template addresses having a decent passenger compartment and a front mounted engine with that ugly profile otherwise you need lay flat passengers and a pancake motor.

There is no one "ideal". If there were, it would be universally used by now.

There are a ton of different constraints that an automotive shape has to satisfy. And each choice made in one affects the possibilities for other choices. As was mentioned, the air curtain thing is pretty meaningless if you have covered or spatted wheels. And if you want more air going under the car, the nose shape will be different than if you want less going under the car. And don't forget cooling ducts and exhausts.

It gets complicated in a huge tearing hurry, and it depends rather a lot on just about every factor going into the car's design.

We have seen "good" noses, more than likely "good enough" ones, such as the well-known Template. But there isn't really any "best" one, IMHO.

-soD

Nose flow smoke imaging
 

MetroMPG took my raw video from 2014 and created: 'Streamlined Toyota T-100 In the Wind Tunnel'.
It's right here at EcoModder.com
If you haven't seen it, it may be of value. It's got the WW-I nose on it. In 1976, Hucho called it 'Optimum', 'Ideal.'
It could use some of the airdam shaved off, maybe 25mm or so.( Unnecessary downforce ). Other than that, I'm pleased.
On some vehicles, the nose constitutes only 5% of overall drag.

Avion is more practical
 

The bellingham made car has the look and the practical design...

Halibut
 

Both 'cod's head' and 'mackerel tail' have been used over time.
At one of Mike Cook's 'Shootouts' at Bonneville, a member of George Poteet's ' Speed Demon' crew mentioned that this particular streamliner shape was inspired by the Coho Salmon.
Considering that salmon can swim against the current, and leap waterfalls, it does imply a certain hydrodynamic advantage.
After sea trails with the USS Albacore ( tuna), the U.S.NAVY determined, in 1953, that all future submarines would have ichtyoid ( fish-like ) external hulls.
Anyone who's watched ' The Hunt For Red October', has seen the circa- 1972, Soviet, Alpha / Akula-Class,nuclear submarine hull hydrodynamic technology. World's- fastest, high-pressure reactor submersibles. Biomimicry.:thumbup:

VW 'Optimum' nose
 

Here's an old image from my photo gallery showing what Hucho's gang came up with.
https://ecomodder.com/forum/member-a...figuration.jpg
It didn't take. sorry!

nose
 

I think you're pressing CTRL-V more than once...

https://ecomodder.com/forum/member-a...figuration.jpg

https://ecomodder.com/forum/member-a...figuration.jpg

Hit the image button up top to paste your image in-line, or the URL one beside it if it's a link.

nose on Honda
 

I built a slip-on over fascia for the '84 CRX. It extended the length 6-inches, enlarged the side radius, lowered the forward stagnation point, reduced the cooling inlet, and faired in all the concavities.
It did helped top speed a little. The tail extension however, was good for most of the speed increase.
https://ecomodder.com/forum/member-a...speed-aero.jpg

CRX nose side view
 

Here's a different view.
https://ecomodder.com/forum/member-a...ap-fillers.jpg
Again, the back of the car was the money-maker.

'optimum nose' 1968-style
 

Here's a low quality image of R.G.S. White's aerodynamic 'recipe', he came up with at MIRA, and published in 1968.
If you look at E-1 on the chart, you'll see a resemblance to Hucho's 'Optimum' nose.
This shape traces back to World War- I.
https://ecomodder.com/forum/member-a...-drag-cars.jpg

WW-I nose
 

Here is the Airco DH.2, with the similar nose.
https://en.wikipedia.org/wiki/Airco_DH.2

The nose is the only thing that DH.2 has going for it. :)

Hyundai deletes air curtains for higher performance ?
 

On November 2, 2016, Hyundai ran an aero-modified IONIQ at the Bonneville Salt Flats, establishing an average 157.825 mph.
Modifications included:
* airdam
* wiper delete
* mirror delete
* lowering
* belly pan
* gaps taped
* Good-Year racing tires
* MOON wheel covers
* ' air curtains abandoned'