Filter out modes according to their modal effective mass fraction

You can apply a threshold to filter out modes with small modal effective mass. This practice can save disk space because fewer modes are stored, and can save computation time because fewer modes are used in the response computation.

This method is an alternative to using the manual method of deactivating insignificant modes using the Response Dynamics Details View panel in the Simulation Navigator. For more information about the manual method, see Select or remove modes to analyze in Response Dynamics.

1. In the Simulation Navigator, right-click the Subcase - Dynamics node and choose Edit.

2. Right-click the Subcase – Dynamics node again and select Edit.

3. In the Solution Step dialog box, next to Output Requests, click Create Modeling Object . Or click Edit if an output requests modeling object already exists.

4. Click the Modal Effective Mass tab.

5. Select the Enable MEFFMASS Request check box.

6. In the Threshold box, enter a threshold.Modes that have an effective mass fraction greater than the Threshold in at least one translational or rotational direction will be output for use in the Response Dynamics solution process when you solve the modal solution. All other modes will be filtered out. Threshold values can be set between 0.0 and 1.0. A reasonable value might be 0.01, which would save modes that have an effective mass greater than 1% in any translational or rotational direction.

7. Click OK.

8. Close the Solution Step dialog box.

How do I

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Filter out modes according to their modal effective mass fraction, Simcenter 3D 2021.1 Series

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