Most interesting car aerodynamically - 2016
 

Mulsanne's Corner: Race Car Engineering Le Mans 2016
http://www.mulsannescorner.com/AudiR18Spa2016-SC1.JPG
http://www.mulsannescorner.com/AudiR...st2016-SC1.JPG
http://www.mulsannescorner.com/AudiR...st2016-SC2.JPG

I know that race car aerodynamics are not explored too much in this forum as the lessons they offer are not typically applicable to street vehicles. However there is so much going on with this R18, how could anyone resist looking at it in awe and wonder?

Several other cars and views in the link.

Check it out.

The side view mirrors are innovative, and it seems like they are working to limit the "width" of the airflow, which will lower drag. But so much of this is for downforce, and safety (the open top fenders) that it is hard to see how very much of this affects us ecomodders.

I agree but some fundamentals could be derived.

Take the front wheel openings, they differ from others in that they are not the top part of an arc, they are an opening in a flattish receding plane.

Now anytime you have to deal with an opening on your street car, this little bit of information could provide some context or serve as a guide.

I know it's a stretch, but the bits and pieces might be applied elsewhere - if we only understood the principles well enough to do so.

I've always wondered what my favorite Volkswagen would look like with updated bits and pieces.

http://ecomodder.com/forum/member-fr...ve12d2-549.jpg

So Graham-Nash headlights, fences on the fenders, single wiper, kschnorkel on the tailfin...

A what?

Please illustrate.

EDIT: like this?

https://www.versustradingco.com/veil...odel-rear-wing
http://forums.pelicanparts.com/uploa...1486566324.jpg

A typo? Yeah that's the ticket. Your infographc will go viral, and it will become a term of art.

http://www.2040-cars.com/_content/ca...300890/001.jpg
http://www.2040-cars.com/volkswagen/beetle---classic/vw-baja-bug-300890/

Like this, only with a tailfin.

Edit: The 1939 Graham headlights.

https://cdn.barrett-jackson.com/stag..._Block_Web.jpg
http://www.barrett-jackson.com/Events/Event/Details/1939-GRAHAM-SHARKNOSE-SC-CONVERTIBLE-22758

That exposed oil plumbing, though... *cringe*

Yeah, a real racer would have drilled holes in the roof. And put big aircleaners with pre-filters inside the cabin.

BTW 'Graham Nash' is a musician; Graham was more closely associated with Willys or Paige; if I've got that right.

Those front fenders look quite odd.


Could eventually run those oil lines along one of the C-pillars to avoid any interference to the rear visibility, but maybe keeping them on the outside with some sort of brushguard could avoid it to irradiate heat inside the cabin.

The sharknose Graham is similar to the bullet-nose Studebaker, from a decade earlier.

I picked the Baja because the intake is raised above the boundary layer, just like the Audi. But everyone focuses on the oil lines, and they are not even braided stainless. :confused:

I'm interested in the fin on the top/outer edge of the front fender. Does it cut down the 'bow wake', like the USS Independence?

I think I was told similar strake features on the L&M (red/white/blue striped) and McMaren (orange colored) from the early 1970's delayed turbulance caused from differing air pressures of the side and top passing air flows.

We were told these were a passing fad never to be seen again. Apparently some engineer thought they were worth revisting.

This race inspired consept is very eco modder do able and applicable.
http://www.mulsannescorner.com/AudiR...st2016-SC3.JPG
This may be the answer to the difficulty of front wheel skirts..

Nice observation, but best not to make them too sharp.

I can just imagine some child falling on them or experiencing them with their tiny hands out of curiosity and then there is a parental lawsuit.

I'd probably end up cutting my shins up when wearing shorts.

And I know my wife is a klutz, I'd never hear the end of it.:D

Could one just use the V-shaped stick on ones already on the market?

They look pretty safe.

Why do they call them vortex generators, they look like fences.

Not enough bodywork ahead of a front wheel to set up the flow.

If the trough is there to recess the 'features', instead of the 'features' managing airflow in the trough; then why is the air fitting allowed?

Would small NACA ducts offerings of twin vortices with no protrusions do the job without the knife edges? The vortices would be counter-rotating and wound be on the inside of the skin/body for a very short time, inches.

Would the negative of a NACA duct, an air tab brand pointy end forward also do the job? Were a maximum size limit is not as big of a consideration, and no holes wanted .

Witch would be more productive for jumping the tire hole, Twin co-rotating or counter-rotating?
Co= all tabs +15° , counter= alternating + - 15°
In the race industry Ive seen them use single or co-rotating like in the pic in post#12 but seldom counter-rotating (as in pairs. At opposite angles +15°and -15° to flow.).

I would think that the "air fitting" is to fill the engine / exhaust with inert gas to prevent corrosion while stored. It looks removable to me.

Simon

VG why?
 

[QUOTE=freebeard;534161)Why do they call them vortex generators, they look like fences.(1

2)Not enough bodywork ahead of a front wheel to set up the flow.(2

3)If the trough is there to recess the 'features', instead of the 'features' managing airflow in the trough;then why is the air fitting allowed?(3[/QUOTE]

1) ,knife edges, VG
Hears a nice video explanation. https://youtu.be/eP-YUDe9HF0
Named after the tip of a conventional wings tendency to cause a vortex from end spill. Fixed with a canard.
2) thats the nice thing about VG they reach up above the separation causing laminar flow to come down and attach . They can help the excessive curves(angle of attack) maintaining attached flow . With todays modern car frontal designs most have attachment to the edge of the front finder opening where everything suddenly goes to s...

MetroMPG years ago did a tuft test video of the G1 Insight's front wheel fender.

https://www.youtube.com/watch?v=EOCV77mjm_w

You'll notice the indentation of the fender right behind the wheel allows the flow to reattach within about 3 inches. There's no vortex generators on the front bumper before the wheel.

I know, holy thread resurrection, but reading this while scanning VG posts made me have to post.

https://m.aircraftspruce.com/catalog.../stolspeed.php

These would probably suffice, and no worries about tearing up shins/kids.

Cool, I've watched the video and read the product reviews.

Well, we all know that something as innocent as paper can give you painful paper-cuts.

Not impossible to hurt one's self with these flexible units, but a huge step in the right direction.

Now I'm curious if anyone's used actual bird feathers as vortex generators. :)


How about man-made feather VG's?

I found what I think to be the same product by a different supplier. They make note of the design being a bit different than older designs.


https://stolspeed.com/nid/43
https://stolspeed.com/uploads/images/Smokey__Clear.jpg
https://stolspeed.com/uploads/images/Shark_teth.JPG
https://stolspeed.com/uploads/images/picture_001.jpg
https://stolspeed.com/uploads/images/Flexible.jpg
The aircraftspruce comments section also complained of UV fatigue of the older offerings.

I'm pretty sure STOLSpeed is the primary supplier/distributor, with Aircraft spruce being a seller.

I feel there's a point where excessive flex negates proper generation of vertices. You'd be able to use fletches for arrows, seeing as how they accelerate from 0 to 200mph pretty much instantly, but I don't think they would be able to maintain their shape well enough to function properly.