CFD Online Discussion Forums (http://www.cfd-online.com/Forums/)
-   CFX (http://www.cfd-online.com/Forums/cfx/)
-   -   Wing Lift and drag coefficient (http://www.cfd-online.com/Forums/cfx/99899-wing-lift-drag-coefficient.html)

 thiez03 April 15, 2012 07:13

Wing Lift and drag coefficient

Hi everyone!!!

I am trying to calculate the lift and drag coefficient of a 3D wing in CFX. I know CFX offers viscous force in X, Y and Z direction.

My flow is aligned with the the x-axis. Therefore, am I right saying that I can use the force in the x-axis to obtain Cd and the force on the y-axis can be used to obtain Cl ??!!

 ghorrocks April 15, 2012 17:51

Quote:
 I know CFX offers viscous force in X, Y and Z direction.
No, CFX gives the total force in X/Y/Z directions. It does not calculate viscous forces separately. But you may be able to calculate it from integrals of wall shear stress.

Your question is correct. This is the standard definition for Cd and Cl.

 thiez03 April 16, 2012 09:26

Thank you so much!!

So basically the force in x-axis is also the drag force (skin friction + form drag etc.) and the y-axis is the amount of lift force produced by the wing.

From these forces I just have to work out, the Cl and Cd.

Thank you once more for your time

Kind Regards

 ghorrocks April 17, 2012 01:18

That's right. force_x/y/z is the total force in that direction.

 All times are GMT -4. The time now is 04:36.