Perform Analyses - Run Simulation

Check Model

Before performing an analysis, it is recommended that you perform a check on the model. This is done by clicking the Analysis Analysis Check Model command. The purpose of checking the model is so that the user can confirm that the FEA model is as intended. There are no holes, no missing boundary conditions, and so on. The checking is done in the Results environment.

Notes:

The date and time when the model was last Checked and last analyzed are stored. If a change is made to the model that affects the results, such as changing the material properties or input in the Element Definition, then the Checked date is updated. When the Checked date is newer than the analyzed date, the following message is given whenever the model is displayed in the Results environment:
The existing results do not match the current model. If the changes have no affect on the results, then it is reasonable to proceed. (Changes include loads, mesh, materials, node numbering, and element numbering.) If the model has changed, the old results should not be used.
If the model has been changed, or if a different version of the software is being used (which could result in different node or element numbering), it is possible that the existing results will not match the new FEA model. If you proceed to use the existing results, check the validity of the results carefully. Alternatively, re-analyze the model to be certain that the results are for the current model. Changes to the model include any geometry changes which can either be deliberate (for example, deleting lines and redrawing them) or transparent (for example, transferring to PV/Designer).
This message appears when doing a restart analysis for those analysis types that show the results while the analysis is running. This behavior is expected.

The geometry decoder checks that all the lines in the model are connected in such a way that valid elements can be formed out of those lines. If there are lines present in the model that cannot be used to form legitimate elements or other decoding problems, a warning dialog will appear. This dialog will allow the user to review the warnings in a text file.

Depending on the severity of the geometry warnings the program will proceed to the Results environment or not, according to the following list:

Clean Model: No warnings, and the model appears in the Results environment. After inspecting the model, go to back to the FEA Editor environment.
Minor Warnings: A warning file is produced, but the model appears in the Results environment. Use the warnings in the text file and Results environment to determine the cause of the problem. The sources of this kind of error are:
- Some of the lines in a part do not form elements as defined in that part. Consequently, nodes are generated, but they are not used to form elements. The warning indicates that nodes were dropped, and usually you will see holes or voids in the model.
Severe Warnings: A warning file is produced. No model is produced, so the Results environment does not appear. Use the text in the warning file to determine the problem, then return to the Interface to fix them. The sources of this kind of error are as follows:
- No combination of lines in a part can form elements. For example, when a part is defined to contain brick elements, but no brick elements can be formed out of the lines in that part, then the geometry translator reports an error.
- Improper material properties.

Run Simulations

Once the model is set up, you can perform the analysis using one of the following two methods:

Click the Analysis Analysis Run Simulation command. This command will run the current design scenario only.
Click the Analysis Analysis Solver Manager command. This command can be used to solve multiple design scenarios, schedule analyses, and to set up other analysis options. See the Solver Manager page for more information.

Note: The previous results will be deleted when the analysis begins, except when doing a restart analysis. Some results that are common to all analysis types, such as weight and center of gravity volume results and log files, may need to be recreated to see those results.)

You can view the progress of the analysis by clicking the Details tab of the output bar at the bottom of the screen. You can view either the analysis log file or the analysis summary file. See the Output Bar page for more information.

Some analysis types will display the model in the Results environment during the analysis (automatic monitoring). This permits the user to monitor the results for expected behavior during the analysis. All the normal features of the Results environment can be used while the analysis is continuing. The analysis types that provide automatic monitoring include:

Nonlinear Structural Analyses (Mechanical Event Simulation, Static Stress with Nonlinear Material Models, and MES Riks)
Thermal (Steady-State and Transient Heat Transfer)

Note: If you change the load case or time step in the Results environment while the analysis is ongoing, then the automatic monitoring of the new results is disabled. The automatic monitoring can be re-enabled with the Results Contours Load Case Options Automatic Advance command.

For other analysis type, once the analysis is complete, the model will be loaded into the Results environment.

Regardless of which command you use to analyze the model, the Mechanical Simulation Job Manager is used to manage and to monitor the solution tasks.