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Thrust Bearing
Thrust bearings are primarily used to restrict the axial motion of the rotor. However, due to the finite cross-sectional area of the collar of these bearings, they also restrict the rotation about the lateral axes. Thrust bearings can be modeled at different levels of detail, as described below.
No Clearance Bearing
This model completely constrains the axial motion of the rotor and the rotation about both lateral axes. Use this model when the effect of the bearing on the dynamics of the rotor assembly is not significant.
Bearing Stiffness and Damping Coefficients
In this case, the thrust bearing is modeled as a spring-damper system with one translational stiffness and damping coefficient along the axis of the rotor, and two rotational stiffnesses and corresponding damping coefficients about the lateral directions. These values are known either by performing experiments or computer simulations. Tabular data of these parameters as a function of the collar motion can be entered as interpolation functions.
Bearing Forces and Moments
You can also directly describe bearing forces and moments as functions of the motion of the collar. If tabular data is available for these relations, you can use interpolation functions for entering the data.
Multiphysics Coupling
When it is necessary is to capture nonlinear effects in the bearing, a multiphysics coupling can be used. For this type of modeling, both the Solid Rotor and the Beam Rotor interfaces can be coupled with the Hydrodynamic Bearing interface.