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Angular velocity in Steady state

One could have extracted the noticed that the moment coefficient (Cm) is not zero, which means that there are some extra torque applied on the turbine. That is in fact true, and we could even use this Cm to calculate the power coefficient (Cp) for this setup. 

It's possible to find at which velocity a VAWT like that would spin in case we applied the very same conditions as of this tutorial. At that angular velocity, there would no extra torque applied on the turbine: if it were to spin faster, a negative torque would slow it down, if it were to spin slower, a positive torque would spin it up.

To find that velocity using the Moving Frame of Reference approach, you can vary the angular velocity (under "Cell zone conditions", open the "inner" condition and change its angular velocity) until Cm is approximately zero. 

If you do that, you will find an angular velocity of about 80RPM.

Mesh Refinement

Make a test refining the mesh (provide geometry?) and check reduced mass imbalance, check change in plots?

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