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Mod Man · 01.29.2008, 08:46 PM

CD (coefficient of drag) is a hugely complex thing to calculate. There is alot more than merely frontal area to consider. There are factors like screen friction (air dragging on the sides of the car), the cowanda affect (spelling?). That is the tendency of the air to hug the body as it rounds a corner rather than skipping off the body creating turbulence and, therefore, drag.

When I designed my CF body, I stood it up (nose in the air) and ran water over the body (steady stream of water running over the body) looking for turbulence in the water and the tendency of the water to hug the body rather than skip off at various curved areas. Water is 800 time more dense than air, yet the same fluid dynamics apply with air as water. So, you can get a good idea of how the air will behave with your body by watching water run over it.

Am I making any sence?

Matt

	(#31)
Mod Man RC-Monster Carbon Fiber Offline Posts: 156 Join Date: Nov 2007	01.29.2008, 08:46 PM CD (coefficient of drag) is a hugely complex thing to calculate. There is alot more than merely frontal area to consider. There are factors like screen friction (air dragging on the sides of the car), the cowanda affect (spelling?). That is the tendency of the air to hug the body as it rounds a corner rather than skipping off the body creating turbulence and, therefore, drag. When I designed my CF body, I stood it up (nose in the air) and ran water over the body (steady stream of water running over the body) looking for turbulence in the water and the tendency of the water to hug the body rather than skip off at various curved areas. Water is 800 time more dense than air, yet the same fluid dynamics apply with air as water. So, you can get a good idea of how the air will behave with your body by watching water run over it. Am I making any sence? Matt