I'm trying to carry out the rotordynamic analysis (complex frequency extraction) of a jeffcott rotor in Abaqus. I need help on how to model the bearings (roller in this case), the type of couplings and boundary conditions so that they can represent the model accurately. There are two bearing locations, where I have defined the bearings by modeling inner and outer race as surfaces, rigid couplings connecting these surfaces to respective master nodes(2) at the center and then using CONN3D2 (join + revolute) connector to connect the two master nodes. I have also put an encastre constraint on the master node for the outer race. I want to know:

1. What kind of DOFs I can define in the kinematic couplings?

2. Is this modeling correct?

3. Is the boundary condition right?

4. Are there any more inputs that need to be taken care of?