Guidelines for Centrifugal Loads

• Centrifugal loads are body loads available in native mode and FEM mode Structure. These loads simulate rigid body rotation for your model. When you define a centrifugal load, you can specify angular velocity, angular acceleration, or both. For each of these load quantities, you need to define either the components, two directional points and magnitude, or the direction vector and magnitude. The resulting body loads act in the directions opposite to the directions of centripetal and tangential acceleration.

• For 2D axisymmetric models, you do not specify the direction for angular velocity because the axis of rotation is always the Y axis of the referenced coordinate system of the axisymmetric model. Only the magnitude of angular velocity is required. Angular acceleration is not available in 2D axisymmetric models.

• For 2D plane strain and 2D plane stress models, only the Dir Points & Mag option is available. You specify From and Magnitude. The axis of rotation and angular acceleration vector pass through that axis location and are perpendicular to the WCS XY plane. The software uses the right-hand rule to determine the direction of rotation about the axis and acceleration direction.

• To determine the direction of rotation, the software applies the right-hand rule to the velocity's sign.

• You can define only one centrifugal load per load set.

• You cannot review a resultant centrifugal load.

• If you are running a prestress modal analysis on a model with a centrifugal load, Creo Simulate will compute modified vibrational modes to take into account the effect of relative circumferential motions, an effect known as spin softening.

• If you select multiple load sets for an analysis and you specify load set scaling when you view the analysis results, then all of the loads in the set will be scaled linearly, even the centrifugal loads. For example, if you want to scale a centrifugal load to reflect a doubling of the angular velocity, you should scale the load set by a factor of four, in order to reflect the fact that a centrifugal load depends on the square of the angular velocity. If there are other loads in the set, you may want to isolate the centrifugal load into its own set, so you can scale it independently.

• For large deformation analyses that use centrifugal loads, the results will scale the body force, but not the velocity or acceleration. You can see the effect of this when you compare results of an analysis that uses one centrifugal load against the results of an analysis that uses a scaled version of the same load. The results will scale correctly in the linear range but, scaling may no longer provide accurate results when you enter the nonlinear range.

Return to Centrifugal Loads.