> ttarleto@ix.netcom.com wrote:
>>
>>> A clark Y wing @ 32sq ft = 174 lb at -10 deg of attack and 256 lb
>at15 deg
>>> THIS IS WITHOUT ANY FLAPS OR GURNEY LIPS.
>>> a 23012 wing with a slotted flap run at 40 deg of attack has a Cl of
>2.7
>>> or 553 lb of force.
>>>
>>> This is a lot of extra grip on a 1200lb modified car.
>>> This is all at 50mph.
>
>Of course that calculation, although correct, only considers a single
>element airfoil. The Phantom has three elements on each wing, all set
>to different attack angles.
>
>Also recalculate for a max. of 20 sq.ft. and it'll still translate to
>even more grip on a sub-800lb. modified car.
>
>"Brent DeWitt" wrote:
>
>>Second, the downforce increases the contact patch area of a wide
>compliant tire, making
>>ultimate shear stress higher.
>
>A portion of this down force is taken up by suspension compliance so the
>contact patch isn't increased all that much. A well tuned autocross
>suspension isn't all that stiff. I've seen small cars with tiny
>contact patches out-corner big cars with fat tires. Cornering ability
>is still a product of good suspension engineering more so than
>downforce.
>
>-c.
You're leaving out an important part of the equation -- weight.
I'm no physics guru, but my gut tells me that a smaller, and therefore
lighter, car is generally going to corner better than bigger and heavier
car (given that the "tire ratio" is proportionate -- you know, size of
tire in relation to the size and weight of the car).
That is, of course, unless the bigger, heavier car has far superior
aerodynamics.
dde
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