Add a Multi-Spool Bearing node to model an intershaft bearing between two rotors running at different speeds. The journal surface of the shaft should be selected in the Boundary Selection section (Beam Rotor: Point Selection). Surfaces on the other shaft connected to the bearing bushing should be selected in the Destination Boundary Selection Beam Rotor: Destination Point Selection).

If the feature is added to a Solid Rotor, or Solid Rotor, Fixed Frame interface, enter the Bearing orientation vector defining the local x direction.

If the feature is added to a Beam Rotor interface, enter the Bearing orientation vector defining the local y direction. The direction given will be adjusted so that it is orthogonal to the rotor axis. The default value is the global y-axis.

You can further modify the axis orientation by entering an angle for the Rotation of the orientation vector around the bearing axis. The direction inferred from the previous setting will be rotated counterclockwise around the rotor axis.

Select Displacement connection — Rigid or Flexible. If Rigid is selected, the bearing acts as an infinite stiffness bearing for the relative translation motion between the two shafts. For the Flexible case, enter the values of the Translational stiffness (2-by-2 matrix) and Translational damping coefficient (2-by-2 matrix). A zero stiffness will make both shafts free for relative translational motion.

Select Rotation connection — Rigid or Flexible. If Rigid is selected, the bearing acts as an infinite stiffness bearing for the relative tilting motion between the two shafts. For the Flexible case, enter the values of the Bending stiffness (2-by-2 matrix) and Bending damping coefficient (2-by-2 matrix). A zero stiffness will make both shafts free for relative tilting motion.

Physics tab with Solid Rotor or Solid Rotor, Fixed Frame selected:

Physics tab with Beam Rotor selected: