1.5.2 Specifying FLUENT Launcher Settings Within Workbench

With the release of ANSYS 12.1, you can use FLUENT in Workbench on either Windows or Linux machines, both interactively and in batch mode. You can also start FLUENT on Linux from a Workbench session running on Windows and you can use the same FLUENT-specific project (and related files) in Workbench using both Linux and Windows hardware interchangeably. The information is this section is the same for both Windows and Linux, except where noted.

When you start ANSYS FLUENT from either type of FLUENT-based system within Workbench, FLUENT Launcher will appear by default. Most FLUENT Launcher settings are available, except for the following options:

• Version (disabled)

• Working Directory (disabled)

• Use Journal File (not available)

The Do not show this panel again option allows you to bypass FLUENT Launcher for subsequent FLUENT sessions. This option is only available when running FLUENT in Workbench.

When using LSF to schedule a FLUENT run from Workbench, by default the working directory is used for checkpointing. You can specify an alternate directory for checkpointing using the LSB_CHKPNT_DIR environment variable.

Note that, when using FLUENT with Workbench on Linux, the FLUENT Root Path option is disabled in the General tab of FLUENT Launcher.

To start your FLUENT simulation on a Linux cluster from a Workbench session running on Windows, use the Use Remote Linux Nodes option in FLUENT Launcher. This option is available when the Parallel option is enabled under Processing Options. Once this option is enabled, the Remote tab is visible when you click the Show More $>>$ button.

The Remote tab of FLUENT Launcher can only be used for 64-bit Linux machines.

For more information about FLUENT Launcher and accessing remote Linux clusters, see the FLUENT User's Guide as well as the separate Addendum to the FLUENT User's Guide.

Specifying FLUENT Launcher Settings Using Cell Properties

You can view the properties of a selected cell in Workbench by selecting the Properties option under the View menu, or by right-clicking a cell and selecting Properties from the context menu. The properties of the selected cell are displayed in the Properties Window in Workbench.

Figure 1.5.1: Properties for FLUENT-Based Systems in Workbench

The FLUENT-based system Setup and Solution cells have the following properties that you can set for FLUENT Launcher:

Use Setup Launcher Settings   (for Solution cells only) allows you to specify that the current system’s Solution cell should use the FLUENT Launcher property settings from the current system's Setup cell.

Precision   allows you to choose either the single-precision or the double-precision solver

Show Launcher at Startup   allows you to show or hide FLUENT Launcher when FLUENT starts.

Display Mesh After Reading   allows you to show or hide the mesh after the mesh or case/data is read into FLUENT.

Embed Graphics Windows   allows you to embed the graphics windows in the FLUENT application window, or to have them free-standing.

Use Workbench Color Scheme   allows you to use either the classic black background color in the graphics window, or to use the Workbench color scheme.

Setup Compilation Environment for UDF   allows you to specify compiler settings for compiling user-defined functions (UDFs) with FLUENT.

Use Job Scheduler   allows you to specify settings for running FLUENT with the available job scheduler. On Linux, you can use either LSF, SGE, or PBS Pro as the job scheduler. On Windows, you can use the Microsoft Job Scheduler, or, when Run Parallel Version and Use Remote Linux Nodes are selected, you can use the LSF, SGE, or PBS Pro job schedulers.

Run Parallel Version   allows you to choose to run the parallel version of FLUENT or not.

UDF Compilation Script Path   (if Setup Compilation Environment for UDF is selected) allows you to specify the path to the UDF compilation script.

Use Remote Linux Nodes   (available only when Run Parallel Version is selected) allows you to run your FLUENT simulation on 64-bit Linux machines.

If Run Parallel Version is selected, the following additional properties are available:

Number of Processors   allows you to set the number of processors you wish to use for the parallel calculations (e.g., 2, 4, etc.).

Interconnect   allows you to set the interconnects you wish to use for the parallel calculations (e.g., ethernet, myrinet, infiniband, etc.).

MPI Type   allows you to set the MPI type you wish to use for the parallel calculations (e.g., MPICH2, HP, etc.).

Use Shared Memory   allows you to specify if shared memory is to be used or not.

Machine Specification   (if Use Shared Memory is not selected) allows you to specify a list of machine names, or a file that contains machine names.

Machine List   (if Use Shared Memory is not selected and Machine List is selected as the Machine Specification) allows you to specify a list of machine names to run the parallel job.

Machine Filename   (if Use Shared Memory is not selected and File Containing Machine List is selected as the Machine Specification) allows you to specify the name of the file that contains a list of machines to run the parallel job.

If Use Remote Linux Nodes is selected, the following additional properties are available (for 64-bit Linux machines only):

Remote FLUENT Root Path   allows you to specify the remote FLUENT Linux installation root path.

Use Specified Remote Working Directory   allows you to specify a directory other than temp directory as the working directory for the remote Linux nodes. When this property is selected, you can specify the directory in the Remote Working Directory property that appears.

Remote Spawn Command   allows you to specify the command to connect to the remote node (the default is RSH).

Use Remote Cluster Head Node   allows you to specify the remote node that FLUENT will connect to for spawning (e.g., via rsh or ssh). When this property is selected, you can specify the remote node in the Remote Host Name property that appears.

If Use Job Scheduler is selected, the following additional properties are available:

Computer Cluster Head Node Name   allow you to specify the name of the compute cluster head node.

Start When Resources Are Available   allows you to start the job when resources are available or not.

Create Job Submission XML   allows you to create the job submission XML file.

Job Submission XML File   (if Create Job Submission XML is selected) allows you to specify the name of the job submission XML file.

If Use Job Scheduler and Use Remote Linux Nodes are selected, the following additional properties are available:

Job Scheduler   allow you to specify the job scheduler for the remote Linux nodes. Available options are LSF (the default), SGE, or PBS Pro.

If LSF is selected as the job scheduler, the following additional properties are available:

Use LSF Queue   allows you to use an LSF queue.

LSF Queue   (when Use LSF Queue is selected) allows you to specify the name of the LSF queue.

Use Checkpointing   allows you to use checkpointing with LSF.

Enable Automatic Checkpointing   (when Use Checkpointing is selected) allows you to automatically checkpoint within a specific period of time.

Checkpointing Period   (when Use Checkpointing and Enable Automatic Checkpointing are selected) allows you to specify a time period for automatic checkpointing.

When using LSF to schedule a FLUENT run from Workbench, by default the working directory is used for checkpointing. You can specify an alternate directory for checkpointing using the LSB_CHKPNT_DIR environment variable.

If SGE is selected as the job scheduler, the following additional properties are available:

SGE Qmaster   allows you to set the machine in the SGE job submission host list.

SGE Queue   allows you to set the queue where you want to submit your FLUENT jobs. Leave this field blank if you want to use the default queue.

SGE PE   allows you to set the parallel environment where you want to submit your FLUENT jobs. Leave this field blank if you want to use the default parallel environment.

Use SGE Settings   allows you to use SGE settings.

SGE Settings   (when Use SGE Settings is selected) allows you to specify SGE settings.

When running FLUENT in Workbench via SGE, there may be instances when not enough time is allotted for FLUENT to start. By default, Workbench performs two steps: starting the FLUENT process and establishing initial contact, with a default wait time of one minute; completing the FLUENT start up process and establishing a final connection (e.g., to spawn parallel nodes, to checkout licenses, etc.), with a default wait time of five minutes. You can change the waiting time increments for each step by defining the FLUENT_WB_MAX_STARTUP_WAIT environment variable before starting Workbench. Note that you cannot define this environment variable within FLUENT Launcher. The value of this environment variable is equivalent to the wait time in minutes for each start up step. So, the overall wait time is double the value specified for the environment variable. Fractions are allowed as values for the environment variable, and any value less than or equal to zero will let Workbench wait indefinitely for FLUENT to start. Note that while Workbench is waiting for FLUENT to start, the Workbench interface is locked, and if, for some reason FLUENT fails to start, you will have to manually kill the Workbench session.

These properties are the same as the settings within FLUENT Launcher. For more information about FLUENT Launcher, see the FLUENT User's Guide as well as the separate Addendum to the FLUENT User's Guide.

Copying FLUENT Launcher Property Settings

Typically, FLUENT Launcher settings are specified in the FLUENT Launcher dialog box when FLUENTis launched from the Setup cell.

By default, the Solution cell uses the same FLUENT Launcher property settings as the Setup cell. If you want the Solution cell's FLUENT Launcher settings to be different than those specified for the Setup cell, you can disable the Use Setup Launcher Settings property setting (see Section  1.5.2) and then set the Solution cell's FLUENT Launcher property settings without impacting the settings for the Setup cell.

You can copy the Setup cell's FLUENT Launcher settings to the Solution cell by selecting the Copy Launcher settings to Solution cell option from the Setup cell's context menu. Likewise, you can also copy the Solution cell's FLUENT Launcher settings to the Setup cell by selecting the Copy Launcher settings to Setup cell option from the Solution cell's context menu (available only when the Use Setup Launcher Settings property setting is disabled).

Note that when the Use Setup Launcher Settings property is enabled, the Solution cell’s distinct set of FLUENT Launcher settings are retained in case you later decide to disable the Use Setup Launcher Settings property.