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If you do that, you will find an angular velocity of about 80RPM.
Mesh Refinement
One can also perform a mesh refinement study. Duplicate your project, import the new refined mesh (found here), "Clear Generated Data" for Results cell, refresh the project and launch Fluent. Remember to use Parallel (2, 3 or 4 cores, no more than that) if available. Also, compute the initialization from farfield1. Run the simulation for about 2000 iterations. This is the new velocity contours.
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