Most interesting car aerodynamically - 2016

[kach22i]

Originally Posted by freebeard

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.

[gumby79]

This race inspired consept is very eco modder do able and applicable.

The bodywork just ahead of the rear wheel is inset in order to accommodate a series of three vortex generators (3) and still stay within the max width regulations. These VGs are designed to route air around the influence of the rear wheel, shooting the subsequent vorticies into the region of the rear cheese wedge (4) so that the air can be better managed inboard and into the base area of the car.

This may be the answer to the difficulty of front wheel skirts..

[kach22i]

Originally Posted by gumby79

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.

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

They look pretty safe.

[freebeard]

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?

[gumby79]

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.).

[LittleBlackDuck]

Originally Posted by freebeard

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?

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

[gumby79]

[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...

[Natalya]

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.

[Joenavy85]

Originally Posted by kach22i

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.

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

They look pretty safe.

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.

[kach22i]

Originally Posted by Joenavy85

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

Other vortex generator suppliers recommend the strongest super-super glue - that's the last stuff that I would want to put on my precious paint job!

(Old style VGs)

The rounded shape of Stolspeed VGs works really well with wing covers or washing. – no points to snag.

Put Feathers on your wings, and fly like a bird!
(Well not quite like a bird of course, but lots better than before!)

The aircraftspruce comments section also complained of UV fatigue of the older offerings.