Modal FRF - Define Loads

After selecting the modes from the Define Modes tab, select nodes at which unit excitations or actual excitations can be applied.

Nodes
Select nodes and activate DOFs for applying excitations.
Import/export the excitation nodes from/to a CSV file.
Unit Input
Generates sensitivity subcases with unit excitations at selected nodes. The number of subcases is equal to the number of selected nodes multiplied by the DOFs.
Create LCS defines unit forces in a local coordinate system (LCS). Create an LCS using the axis-plane method, then apply the excitations in that LCS.
General
Defines external excitations using the CSV, solver deck, and test UNV file. This generates a general FRF subcase with defined excitations.
Use the System Type column to specify general loads in multiple subcases.
Table name
Enter the name for the external excitations defined.


Figure 1. NVH Utilities Browser - Modal FRF - Model tab/Define Loads subtab