On Cylindrical Face

You can use this option only when all the selected faces are cylindrical. Each face can have a different axis. The radial, circumferential, and axial directions for each face are based on its own axis.

Attribute Value
Possible DOFs for solid meshes 3 translations
Possible DOFs for shell meshes 3 translations and 3 rotations
Possible DOFs for trusses 3 translations
3D symbol
translation rotation
Selectable entities Cylindrical faces only
Translations

Radial

Circumference

Axial

Rotations (for shells only)

About radial direction

About circumferential direction

About axial direction

The radial (r), circumferential (θ), and axial (z) directions associated with a cylindrical face are illustrated in the figure.

Example

Suppose you have a cylindrical face with its axis coaxial with the global Z axis.
  • If you restrain the cylindrical face in the radial direction only: the face will be free to move in the Z direction and rotate around the Z axis. All other four rigid body motions will be suppressed.
  • If you restrain the cylindrical face in the circumferential direction only: the face will be free to move in the Z direction. All other four rigid body motions will be suppressed. In particular, the face will not rotate around the Z axis.
  • If you restrain the cylindrical face in the axial direction only: the face will not move in the Z direction. It will not rotate in the X and Y directions either. It will still be free to translate in the X and Y directions, and to rotate around the Z axis. Therefore, only three rigid body motions will be suppressed.
When a rigid body motion is suppressed for a particular direction, it doesn't mean that the cylindrical face will not deform somewhat in that direction. It means that the cylindrical face is not free to move as a whole in the particular direction.
 
Suppose that there are two casters in the model. You can use the On cylindrical faces option to set the axial translation (z) and the radial translation (r) of the caster pins to zero. The pins are free to rotate in the circumferential direction (Θ).
Shell mesh of the part. You can use the On cylindrical faces option to set the axial translation (z) and the radial translation (r) of the shell face to zero. The face is free to rotate in the circumferential direction (Θ).