Integrating Residual Vectors into Mode-Superposition Transient Analysis – Lesson 10

Can nCode DesignLife software be used with a mode-superposition transient analysis if residual vectors are calculated?

Not directly. Mechanical software includes residual vectors by performing a modal restart just before doing the transient analysis that calculates the residual vectors. Thus, the residual vectors are not included in the original modal analysis system or in its results. There are two methods that might enable you to use a mode-superposition transient analysis with nCode DesignLife software.

Method 1:
Insert "Command Object in the Modal Analysis System and issue MAPDL commands to define the loads and invoke RESVEC to include the residual vectors. If those commands are issued, the modal .rst file should contain the modal stresses associated with the residual vector.

Method 2:

1. In the Transient Analysis System, in the Details Window of the "Analysis Settings" branch, change "Analysis Data Management > Delete Unneeded Files to “No”
2. Insert a Command Object under the Transient folder/branch with the single command "/EOF". This end-of-file command will stop the analysis. Also, ensure that "Definition > Step Selection” is set to “Zero” in the Details window.
3. Solve the transient system. It will not be a complete solve, as the /EOF command will stop the solution after the modal restart. However, since Mechanical software was instructed to keep all unneeded files, the file.rst should contain the modal stresses (if requested) for all of the modes, including the residual vector.