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# Need Formulas for Calculating Aero Forces

## Need Formulas for Calculating Aero Forces

(OP)
Can anyone provide the basic calculations for converting Cd and Cl in real force numbers. I have volumns of tunnel data in coefficient form and I need to convert it to force numbers so the end user can understand it.
Thanks
Replies continue below

### RE: Need Formulas for Calculating Aero Forces

Ummmm.....I'm presuming this is what you are looking for:

L = 0.5*(rho)*(V^2)*(Planform Area)*Cl

D = 0.5*(rho)*(V^2)*(Planform Area)*Cd

where L = Lift
D = Drag
rho = fluid (air?) density
V = relative freestream velocity of working fluid

Cheers,

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