You know because this is an aerodynamic Point in Space within an airfoil...
I am not sure without a wind tunnel you could actually find it....
in a wing... you could take the widest points and draw a cross... the point
at which they intersect... would be pretty close to the center of
Pressure.... as the angle of attack changes the center of Pressure moves
fore and aft... not Lots but some....
My thoughts on the aerodynamics of Cars isn't like some of you... your
knowledge is based in Facts... some through experience and some through
education... mine is based on Aircraft stuff.... Helicopters in
particular.. so I am trying to translate a life time of teaching this stuff
and schooling to the practical application in a Race car....
In other words... I have a ton of useless knowledge running around in a Pea
Brain that doesn't apply to squat.... But I think the theory remains the
same...
Take a Small frontal area and make it smooth... then put as much speed in
it as you can afford... and GO FAST.... hmmm Great in theory
Keith Turk
Austin Healey 100 / Bugeye / Box Sprite / Bonneville Land Speed Racer
Camaro ( D Gas Altered )
----------
> From: John Beckett <landspeedracer@email.msn.com>
> To: Keith Turk <kturk@ala.net>; land-speed@autox.team.net
> Subject: Re: Center of Pressure and Gravity
> Date: Wednesday, June 16, 1999 6:46 AM
>
> OK totaly confused. So how does one find the center of pressure for any
> given vehicle?
>
> JB
>
> -----Original Message-----
> From: Keith Turk <kturk@ala.net>
> To: land-speed@autox.team.net <land-speed@autox.team.net>
> Date: Wednesday, June 16, 1999 6:38 AM
> Subject: Center of Pressure and Gravity
>
>
> >The Term Center of pressure refers to the Point at which all aerodynamic
> >forces take place on an airfoil... It Moves with changes in speed as
there
> >is a change in aerodynamic Properties of air flow over the car....
> >
> >Someone started to talk about Center of Gravity and the two types of
Roll
> >charatarisics.... Static and Dynamic...in relation to CG...
> >
> >Picture a standard Kitchen chair.. if you balance it on two legs so that
it
> >stays upright... the center of Gravity is dead over the point at which
it
> >is being Balanced.. if you tilt it fore or aft... it will fall over.. as
a
> >result of the Center of Gravity being placed outside the point at which
it
> >is balanced... this is called Static Rollover
> >
> >On a Car you have four wheels and a very Low CG to get the weight
outside
> >of the point it is being balanced on is really tough to do.... Right up
> >till you consider the second kind of Rollover which is Dynamic... and it
> >has to do with the Rolling Moments being aided by the dynamics of weight
> >being shifted as the car spins.... Picture our chair again only this
time
> >take the front Legs and place them closer to the floor and give it a
> >shove.. the weight is forward of the pivot point but the inertia of the
> >shove and stored energy in the mass will cause the chair to go over
> >backwards if pushed hard enough... that is dynamic Rollover..
> >
> >To relate this to a Car... think about the Long Slides Tom was talking
> >about and then think about what happens when a wheel digs into the
salt...
> >causing the car to start to pivot about that Point.... Kinda like our
back
> >chair legs... if the shove is hard enough the car will start to roll
...
> >
> >If your not confused enough let me know.. I can be really confusing....
> >Keith Turk
> >Austin Healey 100 / Bugeye / Box Sprite / Bonneville Land Speed Racer
> >Camaro ( D Gas Altered )
>
>
>
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