graphed. Pair-based contact data are also available. The result data are written to a file named Job-
name.nlh.
For example, a reaction force-deflection curve could indicat e when possible buckling behavior occurs.
Nodal results and contact results are monitored at every converged substep while element nodal data
are written as specified via the OUTRES setting.
You can also track results during batch runs. To execute, either access the Launcher and select File
Tracking from the Tools menu, or type nlhist150 at the command line. Use the supplied file browser
to navigate to your Jobname.nlh file, and click on it to invoke the tracking utilty. You can use this
utilty to read the file at any time, even after the solution is complete.
To use this option, use either of these methods:
Command(s):NLHIST
GUI: Main Menu> Solution> Results Tracking
5.3.3.4.1.1. Prestress Effects
You may include prestress effects in your analysis. This requires element files from a previous static (or
transient) analysis; see Performing a Prestressed Transient Dynamic Analysis (p. 129) for details.
Command(s):PSTRES
GUI: Main Menu> Solution> Unabridged Menu> Analysis Type> Analysis Options
5.3.3.4.1.2. Damping Option.
Use this load step option to include damping. Damping in some form is present in most structures and
should be included in your analysis. In addition to setting ALPHAD and BETAD on the Solution Controls
dialog box (as described in Using the Transient Tab (p. 114)), you can specify the following additional
forms of damping for a full transient dynamic analysis:
- Material-dependent alpha and beta damping (MP,ALPD and MP,BETD)
- Element damping (COMBIN14, and so on)
To use the MP form of damping:
Command(s):MP,ALPD or MP,BETD
GUI: Not accessible from the GUI.
Note that constant material damping coefficient (MP,DMPR) is not applicable in transient analysis. See
Damping (p. 2) for further details.
5.3.3.4.1.3. Mass Matrix Formulation
Use this analysis option to specify a lumped mass matrix formulation. We recommend the default for-
mulation for most applications. However, for some problems involving "skinny" structures, such as
slender beams or very thin shells, the lumped mass approximation might provide better results. Also,
the lumped mass approximation can result in a shorter run time and lower memory requirements.
To use this option:
Command(s):LUMPM
GUI: Main Menu> Solution> Unabridged Menu> Analysis Type> Analysis Options
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