Radial Roller Bearing
Add a Radial Roller Bearing node to model a surface of the component supported by a roller bearing. The selected boundaries should form a cylindrical surface representing the surface connected with the inner race of the bearing. The forces on the rollers are computed using the Hertz contact theory. The built-in variable for the roller force distribution has the form <physicsName>.<RollerBearingTag>.fb[x,y,z], for example mbd.rrb1.fbx.
Bearing Orientation
Use the settings in this section to define the local y-direction of the bearing. Subsequent vector and matrix inputs are specified in the local directions specified here.
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 y-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.
Geometric Properties
Select a Bearing Type — Deep groove ball bearing, Angular contact ball bearing, Self aligning ball bearing, Spherical roller bearing, Cylindrical roller bearing, or Tapered roller bearing. Then go to the relevant section below to continue defining the properties.
Deep Groove Ball Bearing
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Select either Single row or Double row to specify if the bearing consists of single or double rows of rollers.
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For a Double row bearing, enter the Axial distance between the roller centers.
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Enter the renaming geometric properties Number of balls; Ball diameter; Radial clearance; Pitch diameter; Contour radius, inner race; and Contour radius, outer race to define the bearing geometry.
Angular Contact Ball Bearing
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Select either Single row or Double row to specify if the bearing consists of single or double rows of rollers.
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For a Double row bearing, enter the Axial distance between the roller centers.
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Enter the remaining geometric properties Number of balls; Ball diameter; Radial clearance; Pitch diameter; Contour radius, inner race; Contour radius, outer race; and Initial contact angle to define the bearing geometry.
Self Aligning Ball Bearing
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Select either Single row or Double row to specify if the bearing consists of single or double rows of rollers.
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Enter the geometric properties Number of balls; Ball diameter; Radial clearance; Pitch diameter; Contour radius, inner race; and Contour radius, outer race.
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For a Double row bearing, enter also Initial contact angle.
Spherical Roller Bearing
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Select either Single row or Double row to specify if the bearing consists of single or double rows of rollers.
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For a Double row bearing, enter the Axial distance between the roller centers and Initial contact angle.
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Enter the remaining geometric properties Number of rollers; Roller diameter; Radial clearance; Pitch diameter; Contour radius, inner race; and Contour radius, outer race to define the bearing geometry.
Cylindrical Roller Bearing
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Select either of Single row or Double row to specify if the bearing consists of single or double rows of rollers.
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For a Double row bearing, enter the Axial distance between the roller centers.
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Enter the remaining geometric properties Number of rollers, Effective length of the roller, Radial clearance, and Pitch diameter to define the bearing geometry.
Tapered Roller Bearing
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Select either of Single row or Double row to specify if the bearing consists of single or double rows of rollers.
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For Single row bearing, enter the Axial offset of roller center.
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For Double row bearing enter the Axial distance between the roller centers.
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Enter the remaining geometric properties Number of rollers, Roller diameter, Effective length of the roller, Inner race clearance, Outer race clearance, Flange clearance, Pitch diameter, Cap radius, Semi cone angle, Roller axis orientation, Cap angle, and Flange contact angle to define the bearing geometry.
Material Properties
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Enter the material properties Young’s modulus, inner race and Poisson’s ratio, inner race to define the elastic properties of the inner race in the bearing.
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Select Outer race material — Same as inner race or User defined. If User defined is selected, enter the values of Young’s modulus, outer race and Poisson’s ratio, outer race.
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Finally select Roller material — Same as inner race or User defined. If User defined is selected, enter the values of the Young’s modulus, roller/ball and Poisson’s ratio, roller/ball.
Foundation Properties
Select one of the Fixed, Moving, or Flexible foundation options. In the Moving and Flexible cases, the subnodes Moving Foundation or Flexible Foundation are automatically added.
To know the details of contact force computation in different roller bearings, see the theory for Radial Roller Bearing in the Rotordynamics Module’s User Guide.
Location in User Interface
Context Menus
 Multibody Dynamics>Radial Roller Bearing
Ribbon
Physics tab with Multibody Dynamics selected:
Boundaries>Multibody Dynamics>Radial Roller Bearing