Rotating forces and unbalanced masses

Rotating forces

You can apply a rotating force as a translational nodal force excitation in a frequency event. A rotating force is a Spectrum Force function in the frequency domain, applied to a rotation axis on the model.

To apply a rotating force, you first need to create a Spectrum Force function and store it in a function AFU file. Then, you apply it to a node about a given axis in a translational nodal excitation. Internally, the software generates two force excitations for the event. For example, if the Rotation Axis is the X-axis (that is, the force rotates on the Y-Z plane), and the starting phase angle is

from the Y-axis, the two component excitation functions are calculated by:

and

where

is the rotating force.

Note:

In Response Dynamics, the nodal coordinate system is used to define the rotating forces.

Unbalanced masses

A mass unbalance is a special case of a rotating force. To define a mass unbalance, you must create a Spectrum Force function as:

where:

m= mass

e= eccentricity

Then, you can use this function as a function of rotating force and apply it as a translational nodal excitation in a frequency event.

How do I

Convert SRS/PSD/Time functions

Import test data into Response Dynamics

Create nodal and enforced motion excitations

Create distributed load excitations

Create static excitations

Create a drop impact or constant velocity impact simulation

Calculate random RMS functions from PSD input

Using Fast RMS Fitted PSD functions

Create rotating force excitations

Correlate two PSD excitations

Create DDAM excitations

Learn more

Excitation loads

Response Dynamics Function Toolkit

Using pulse functions for shock analysis

Velocity Impact excitations

PSD correlation

Look up more details

Function requirements by excitation type

Function parameters by event type

Quick links

Command reference

Pre/Post video examples

Bulk Entry Descriptions

Simcenter 3D tutorials

Browse Simcenter 3D help by product area

Rotating forces and unbalanced masses, Simcenter 3D 2021.1 Series

© 2020 Siemens

window.mainLanguage="en_US"

window.delivId=""

window.projectId=""

MathJax.Hub.Config({ TeX: { extensions: ["autoload-all.js"] }, tex2jax: { displayMath: [ ] }, "SVG": { scale: 125 } });