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CL-alpha 3D

CL-alpha 3D

CL-alpha 3D

I am currently trying to calculate 3D CL values to compare with my 2D xfoil data. I understand that the 3D values will have a lower CLmax (~90%) with a stall alpha which is higher.

I have a dCl/dalpha for my 2D of 0.1132 (per degree) and Clmax of 1.667. But require a 3D CL-alpha plot. How can I do this?


RE: CL-alpha 3D

Design the wing & fuselage, I think. At least determine the AR. The 3d value have to do with tip & fuselage interactions that are determined by the yet to be known 3rd dimension.

RE: CL-alpha 3D

I have a AR of 9.27, I am trying to theoretically calculate the 3D cl-alpha plot for the Piper PA-38 Tomahawk if this helps?

RE: CL-alpha 3D

a pretty quick search of wiki lead to "lifting line theory" which includes ...

CL3d = CLa*(AR/(AR+2)*a

CLa = 2D lift curve slope
a = AoA
AR = aspect ratio

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