Chris Swearingen

iTrader: (1)

Ok, all you track aero knowledgeable people out there, lets assume for a moment that your design parameter is total area of all canards cannot exceed 172 square inches.

What is the optimal setup? A single large one on each side? Two per side? Is there any "science" regarding angle of attack?

Why the 172 you ask? It's a SSM autocross thing. Here is the current very rough prototype for my splitter and canards, but I am open to better ideas.
Thanks,
--Chris

WonTon

iTrader: (17)

that looks pretty good! is that piece you got cut out within the limit?

SSM has alot of dumb rules it seems!

Full_Tilt_Boogie

iTrader: (1)

On pro touring cars you usually see upright pieces along the outside used to separate the high and low pressure areas on the upper and lower sides of the canard, just like you see on a spoiler.







I wish i could find better examples, but you get the idea

WonTon

iTrader: (17)

^^^^^^ what he said!

i forgot all bout that!

Full_Tilt_Boogie

iTrader: (1)

You ever see them on big money touring cars? with the crazy multi level canards and **** all over. I wish I could find some damn pics, haha

hustler

iTrader: (6)

Chris Swearingen

iTrader: (1)

My car would be sooooo much faster without rules, but then again so would everyone's. The good thing about the rules is that they are the same for everybody. Part of the challenge, for me at least, is to figure out how to make the most of what is allowed but still be 100% legal.

The one taped on is the "maximum" legal size. Nothing says it can't be smaller. I think the turned up edge is legal as well. The splitter is actually a couple of inches shorter than it can be. The final version may be a little bigger.

Chris Swearingen

iTrader: (1)

Cool but slightly outside the rules. Can anyone tell where the splitter ends and the canards begin?

KPLAFIN

iTrader: (1)

Benz like them flat:

Stein

iTrader: (46)

L0oks like a friggen snow shovel. I don't doubt that it works and all of them are wearing them but come on...

Full_Tilt_Boogie

iTrader: (1)

I'd daily drive it fo sho

Full_Tilt_Boogie

iTrader: (1)

you could always do this

WonTon

iTrader: (17)

good god!

it looks so stupid it has to be functional! haha






its FWD, hah it needs all the downforce in the front it can get!

boileralum

iTrader: (8)

Pretty sure that's the Pike's Peak Suzuki Escudo that dominated all the top speed records in Gran Turismo 1&2.

bellwilliam

iTrader: (1)

canard is just like wing. it does stall if it is too steep. so anything over 25 degree is a no no. probably a little less.

canard gives very little down force comparing to splitter. my guess is less than 10% of total front down force. but I install it, because I use it more as a tire spat than a canard. front tires generates a ton of drag and lift.

fooger03

iTrader: (2)

+1,000

The turn-up on the outside edge of the canards is designed to help the canard to not stall by holding the high pressure onto the top side of the canard. It should be noted though, that a lot of these canard pictures are missing a turn down as well. You see, the bottom side of the canard is significantly lower pressure. If you "T" the edge of the canard (close off the high pressure up top AND the low pressure down bottom) instead of simply a turn-up, then you keep ambient air from spoiling the low pressure area beneath the canard. These turn-ups and "T"s literally make the canard act as if it had a larger area than it does. Does your 172 sq-in max limit the vertical area too, or just the horizontal surface?

You may want to consider looking into airfoils as well as canards. you will have to position an airfoil farther to the side of the car than a canard to get the benefit from it (and you may end up fuxxoring it up by running into crap b/c it's adding a couple inches to the width of the car), but in essence it would be a front-wing which would generate downforce much like a legitimate rear wing. It also wouldn't become nearly as much of a hinderance from an aero-drag perspective as a canard would. Just a thought, discard if you like.

Braineack

iTrader: (62)

Canards

Nissan Skyline Gtr Jgtc Canards

Also known as dive planes or dive plates, since they resemble the winged appendages on submarines, canards help generate downforce in two different ways. First, the canard redirects the oncoming air's momentum upwards, which causes a downward force on the canard. This is only moderate, since the velocity near the skin is significantly slower than in the free stream. In addition, canards generate strong vortices that travel down the sides of the car and act as a barrier. If the canards are positioned correctly, these strong vortices act to keep high-pressure air around the car from entering the low-pressure underbody region, thus maintaining more downforce. If air was allowed to enter the underside, the pressure would inevitably rise, reducing downforce. Therefore, these strong vortices act like a virtual curtain or dam, restricting higher-pressure air around the car's sides from entering the underbody region. As a result, the low pressure under the car is maintained and downforce is maximized. Unfortunately, canards are not very efficient, since the strong vortices create a significant amount of drag. They are more useful for fine-tuning aerodynamic balance.



Automotive Aerodynamics - Sport Compact Car Magazine

webby459

iTrader: (8)

SSM aero rulez quoted below. Chris, did the Nov fastrack prop for the canards get adopted as written here? Just figured this would help in the discussion a little, canard stuff in italics, below:

L. Aerodynamic Aids: Wings may be added, removed, or modified.
Non-OE wings may only be attached to the rear deck/hatch area
behind the centerline of the rear axle. The total combined surface
area of all wings shall not exceed 8 square feet as calculated
per Section 12.9. The number of wing elements is limited to 2.
Wings, and any component thereof, may not extend beyond the
vehicle width, as defined by the outermost portion of the vehicle
doors, less mirrors, door handles, rub strips, and trim. In addition,
no portion of the wing or its components may be more than
6" forward of the rear axle, more than 0" beyond the rear most
portion of the bodywork, or more than 6" above the roofline of
the vehicle, regardless of body style. For convertibles and roadsters,
the highest portion of the windshield frame will be considered
the highest portion of the roof.
Reinforcements to the wing mounting area may be used, but
may serve no other purpose. Body panels to which a wing
mounts must remain functional (e.g. trunk lids and rear hatches
must open). Wing endplate surface area is limited to 200 square
inches each and limited to a maximum of two.

Add to 16.1.L: “Canards are allowed and may extend a maximum of 6 inches forward of front bodywork/fascia
as viewed from above. No portion of the canard may extend past the widest part of the front bodywork/fascia as
viewed from above. Canard area will be measured in the same manner as wings using 12.10. Canard area may not
exceed 15% of total wing allowance. The sum of canard area and rear wing area may not exceed the total wing
allowance.”

M. Front splitters are allowed and shall be installed parallel to the
ground (within +/-3 degrees fore to aft) and may extend a maximum
of 6 inches from the front bodywork/fascia as viewed from
above. Splitters may not extend rearward past the centerline of
the front wheels. No portion of the splitter may extend beyond
the widest part of the front bumper/fascia as viewed from above.

Chris Swearingen

iTrader: (1)

I probably should, but don't care about any drag penalty. I am 300+ rwhp at around 2100 lbs and very rarely get out of second gear. (the 3.63 rear end may change that to never) I am going to take the conservative approach and say that the turn up on the ends would be considered part of the surface area.

I see a lot of the pictures that show two per side. Is that "better" or just more visually appealing?

I am waiting to hear back from the rules makers on the use of side skirts. I have some "designed" that will effectively seal the sides of the car.

So given the max downforce without regard to drag, and little need for generation of vortexes to seal the sides, what say you?

webby459

iTrader: (8)

Unfortunately, the above prevents Chris from using the canard as a tire spat, as William suggested. Can any of you smarties think of a way to shape the canard to resemble the function of a spat? I would think this would be of some benefit to Chris. Maybe leave the vertical end plane off the canard in order to direct turbulent airflow away from the tire/flare? Or, even better, use a vertical end plane presented at a longitudinal angle to direct airflow outside of the tire/flare area? Just thinking out loud.