ask help about flapping wing UDF
 

Hi
I want to make a Dynamic Mesh for flapping wing.It has three DOF, including Positional angle, Elevation angle and Attack angle.Positional angle and Elevation angle can be rotated by axis Z and axis Y.But the rotation axis of Attack angle is along the flapping wing spanwise , varies with time.
I want to know how can I define the rotation axis of Attack angle in UDF, and set counterpart in Fuent.
Thanks.

Best wishes
Peng