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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