[Flegmatoid]

Hi All,

there is a nice UDF example which works well on 16,17 fluent.
In 18.2 interface gaps occur, size of which does correlate to the time-step size.
Ultimately, Fluent starts to complain:

Info: Interface zones overlap for mesh interface int1.
  This could adversely affect your solution.
  0: Warning: Failed to correct face handedness of 186 out of 195 left-handed faces on the sliding interface zone 40.

Below are the screenshots of mesh motion preview with 0.005s




disabling the following code in UDF removes the error, but obviously - blade pitching won't happen

omegac = 60;//radians per second
omegar = -omegac*(25*M_PI/180.)*cos(theta0+thetap1);//+-25 is max pitching angle
*omega = omegar;

18.2 problem tested:
-on ICEM mesh
-on Fluent mesh
-on 2D mesh
-on 3D mesh

Edit: Same problem on Ansys 19. And, on 17.2 as well (with increasing the time-step to 0.0016)

coordinate (origin in UDF) motion confirmed to be perfect
coordinate accuracies are within 10^e-9 (the center point)

Something *omega related

Any ideas?