Regarding curve length on wall surface
 

Dear All,

I am interested to plot the angle vs. vorticity over a square cylinder. In fluent XY plots, I can get the curve length vs. vorticity and managed to convert curve length to angle in excel.

However, the problem is first point on the surface. If the geometry is changed, the first point is changing. Also, the starting point is not at the origin.

Please help me in resolving this issue. I am attaching the image of two of my models which represents the changing in first point (blue circle).

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Krishna.