[weij2018]

Hello, everyone! I have got this question about simulating flow in the bearing. I define the speed of revolution in the bearing domain, and I also need to define the speed of rotation of the ball of the bearing. I insert a new coordinate frame, and its origin is set in the center of the ball. I want to set the frame as a rotating frame, but after that, I can't define the wall velocity of the ball by the new rotating frame to define a relative speed. If I set the frame as stationary, I can define the wall velocity of the ball by the new rotating frame, but the frame is stationary.
And here is my question: if I set the new frame as stationary, will the revolution speed of the bearing domain be added to the ball for I want to define a relative speed of the ball; otherwise, if I set the new frame as a rotating one, how could I define the wall velocity?
Thank you very much!