Schedule Analyses

Instead of performing the analysis live, you can schedule the analysis to be performed at a later time. For example, you can create several design scenarios (or several models) during the day and schedule them to run overnight. The Windows® Task Scheduler is used to execute scheduled tasks. The Solver Manager is used to create the scheduled event entries. The basic steps are as follows:

In the FEA Editor, open or create the model, apply the loads and constraints, and define the element data, materials, and analysis parameters. Do everything that you would normally do prior to clicking the Run Simulation command, but do not run the simulation.
Important: To solid mesh all applicable parts, use the Check Model command prior to scheduling a solution job. When running a job from the user interface, solid meshing occurs automatically, if not already completed. However, when a job is run from the Task Scheduler, solid meshing is not performed automatically. The analysis will not be successful if the model has never been checked (or previously solved) since the last time it was surface meshed. For the greatest convenience, create additional design scenarios after checking the first design scenario. The solid mesh will be copied from the first design scenario. You will not have to perform a Check Model operation on the subsequent design scenarios.

Tip: It may be necessary to create one or more dummy files to set up certain analyses. In other cases, you cannot fully set up an analysis until after the results of a prerequisite analysis are available. In the latter case, you cannot schedule the solutions of both the prerequisite and the dependent analysis. See the Multiphysics Considerations when Scheduling Analyses section below for more information.
Click Analysis Analysis Solver Manager to access the Solver Manager dialog box.
Activate each design scenario that you wish to solve by checking the appropriate boxes in the Include in Solution Set column.
To schedule a solution, click in the Start Time column within the appropriate design scenario row . The current date and time appears, or the most recently specified start time.
Activate the checkbox at the left end of the Start Time column to schedule a specific start date and time.
Click on the hour, minute, and/or second value and type in the hour, minute, and/or second of the time when you want the solution to start. Design scenario solutions can start at the same time or at unique times.
Important: If one design scenario is dependent upon the results of another, and you are able to fully set up both scenarios, then schedule the start times of each accordingly. The prerequisite solution must finish before the dependent one begins. See the Multiphysics Considerations when Scheduling Analyses section below for more information.
Click on the icon at the right end of the Start Time column to access a pop-up calendar. Navigate to the desired month using the forward and backward arrows, if necessary. Then, click the date on which you want the solution to start.
Repeat steps 4 through 7 for each additional design scenario within the current model that you want to schedule.
Enter your User Name and Password in the provided fields. The Task Scheduler requires your computer Windows® login credentials.
Click Analyze. This action dismisses the Solver Manager dialog box and add the solution task or tasks to the Windows® Task Scheduler.
Repeat steps 1 through 10 for any additional models you want to schedule to be solved.
Each analysis starts at the scheduled time, based on the state of the model when the analysis begins. Any changes made to the model between the time it is scheduled and the solution start time affect the analysis (provided those changes are saved).

Note: Once you have scheduled one or more solutions, you do not need to keep Simulation Mechanical running. You can even log out of Windows®, but the computer must stay on. The scheduler is a system-level service, which runs the simulations from the command line.

When the scheduled time arrives, a command window appears on the Windows® desktop. The solution is run from the command line. The Simulation Mechanical user interface is not aware or the running solution and does not monitor its progress. After the scheduled solution is finished, you can open the model in Simulation Mechanical to review the results. If the Results environment is not available, perform a Check Model operation. Answer Yes when warned that the results do not match the current model setup. The model will then be displayed in the Results environment.

Multiphysics Considerations when Scheduling Analyses

Results of one analysis can often be used as an input or load in another analysis. Multiphysics is a term used to describe combining analysis types in this fashion.

Different models, and the design scenarios within the models, can sometimes be run concurrently, and sometimes not. There are several multiphysics schemes that require the analyses to be run sequentially. Sometimes the two analyses can be set up and scheduled to run sequentially. In other cases, the models must be set up and run one at a time. Here are some examples of possible multiphysics schemes.

Thermal Stress

Temperatures can be read into a linear stress analysis from a steady state or transient heat transfer analysis to calculate thermal stresses. There are two methods for applying the temperatures:

In the Thermal tab of the Analysis Parameters dialog box, specify the Simulation Mechanical or Simulation CFD model, design scenario, and load case to use as the source of nodal temperatures.
Use the Loads from File command to specify the name of the results file to use for inputting temperatures.

In Method A, you must run the thermal analysis before you can set up the subsequent stress analysis. You cannot select the thermal source model, design scenario, or load case until the results of that analysis exist. In such cases, you cannot use the Solver Manager to schedule both the prerequisite (thermal) and the dependent (stress) analysis solutions. You cannot schedule a solution when the model setup is incomplete. First, run the thermal analysis. Then, you can complete the setup of the stress analysis and run it.

Conversely, for Method B, you can fully set up both the thermal and stress analysis scenarios and schedule them to run sequentially. A dummy thermal results file is required to facilitate the setup of the stress analysis. Follow these steps:

Using Windows® Notepad, create a dummy results file. Name the file DS.TO for a steady-state heat transfer analysis and DS.TTO for a transient heat transfer analysis. Place the file in the thermal design scenario folder of the source model.
Use this dummy file to set up the stress analysis. Right-click in the display area with nothing selected to access the Loads From File command and select the source file. Also, specify the Load Case from File, Structural Load Case, and Multiplier values. Click here for more information.
Define a load curve to control the temperatures when performing a nonlinear stress analysis but using steady-state temperatures.
Open the Solver Manager dialog box. Schedule the thermal and stress analysis solutions to run sequentially. Allow an adequate lag time between the two start times to ensure that the thermal solution can finish before the stress solution begins.

Stress and Displacement Due to Electrostatic Forces

You can choose to output electrostatic forces from an electrostatic analysis and use those forces as a structural load in a stress analysis. The workflow is the same as the second thermal stress method detailed above. For this workflow, the dummy filename is DS.EFR, and the force results are also applied to the stress analysis using the Loads From File command.

Using Windows® Notepad, create a dummy results file. Name the file DS.EFR. Place the file in the electrostatic design scenario folder of the source model.
Use this dummy file to set up the stress analysis. Right-click in the display area with nothing selected to access the Loads From File command and select the source file. Also, specify the Load Case from File, Structural Load Case, and Multiplier values.
Define a load curve to control the electrostatic force load when performing a nonlinear stress analysis.
Open the Solver Manager dialog box. Schedule the electrostatic and stress analysis solutions to run sequentially. Allow an adequate lag time between the two start times to ensure that the electrostatic solution can finish before the stress solution begins.

Joule Heating

The electrical current results from an electrostatic analysis can be used as an input in a thermal analysis to produce Joule heating effects. For this workflow, the source of the electrostatic current results is specified in the Electrical tab of the Analysis Parameters dialog box.

Using Windows® Notepad, create a dummy results file. Name the file DS.EFO. Place the file in the electrostatic design scenario folder of the source model.
Use this dummy file to set up the stress analysis. Go to the Electrical tab of the Analysis Parameters dialog box. Activate the option Use electrostatic results to calculate Joule effects flag.
Add a Heat Generation load to the parts carrying electrical current. Specify an Internal Heat Generation value of 1. The actual heat generation, based on the electrostatic current results, is substituted on an element by element basis when the solution is run.
Define a load curve to control the heat generation load when performing a nonlinear stress analysis.

Editing a Scheduled Task

To edit the start time of a task after it has already been scheduled:

Use the Windows® Task Scheduler (Start All Programs Accessories System Tools Task Scheduler).
Locate and select the task that you wish to modify. The name of each Simulation Mechanical scheduled task is of the form [ALGOR] Task_x.
To delete the task, click the Delete command. Otherwise, proceed to step 4.
To change the start time or date, click the Properties command.
- Click the Triggers tab.
- Click Edit.
- Change the start time or date and then click OK.

Sequential Analyses (Batch File Method):

You can create a batch file to run analyses sequentially. The program that enables this ability is algor.exe. The batch file technique can be useful when you do not know how much time to allow between prerequisite and dependent solutions. A batch file can also be used to automate a frequently repeated analysis sequence.

The steps to run a series of analyses in batch mode are as follows:

Use Windows Explorer or My Computer to create a batch file (plain text file) in a folder (right-click in the folder and choose New Text Document). Specify the desired filename. The extension for a batch file is .BAT.
Edit the batch file (right-click the file and choose Edit).
Add a line to the batch file for the first model to analyze. The syntax is as follows:
```
“drive:\{path to Autodesk Simulation Mechanical}\algor.exe -s list drive:\{path to model}\{model filename}.fem”
```
where
- drive:\{path to Autodesk Simulation Mechanical } is the complete path to the location of the Simulation Mechanical software. (The path specification is not required if this path is included in the PATH environment variable.)
- algor.exe is the program that runs the analysis. The path and algor.exe string must be enclosed in quotation marks (" ") if the path includes spaces.
- -s list is the list of design scenarios to analyze. The list can be any of these items:
  - All. Sequentially process all scenarios in the file. This option must be used alone.
  - Active. Process the active (loaded) scenario in the file. This option must be used alone.
  - m,n,r-t, Sequentially process individual scenarios separated by a comma (scenarios m, n, and so on) and/or a range of scenarios separated by a hyphen (scenarios r through t). A design scenario cannot be listed more than once.
- drive:\{path to model }\ is the complete path to the location of the model.
- {model filename }.fem is the name of the model to analyze, including the .fem extension. The path and filename string must be enclosed in quotation marks (" ") if any spaces are present in the path.
Repeat the above step for each additional file to analyze.
Save and exit the batch file.
Double-click the batch file to start the analyses. Alternatively, use Windows® Task Scheduler (Start All Programs Accessories System Tools Task Scheduler) to schedule the batch file to start at a specific time.

For example, the following batch file analyzes Design Scenario 1 and 3 in the model named bracket. Once that is model finished, Design Scenario 2 through 5 are analyzed in the model named structure. Then, all design scenarios in the model named pipe run are analyzed.

"C:\Program Files\Autodesk\Simulation 20xx\algor.exe" -s 1,3 "D:\my FEA models\job1\bracket.fem"
"C:\Program Files\Autodesk\Simulation 20xx\algor.exe" -s 2-5 "D:\my FEA models\job2\structure.fem"
"C:\Program Files\Autodesk\Simulation 20xx\algor.exe" -s all "D:\my FEA models\job3\pipe run.fem"