ANSYS 19.2

The Ansys CFD products is a general-purpose fluid dynamics suite. It has the following components:

  • CFX-Pre - the CFX pre-processor.
  • CFX-Solver - the solver, which may be run from the Launcher or directly from the command line.
  • CFD-POST - the primary post-processing tool for CFX simulations.
  • ICEM CFD  which provides a unified environment for mesh generation, combining multiple functionality under a single GUI. Features include:
    • Manager - project management, settings and file I/O.
    • Geometry creation/repair - Tool to create/add geometry as well as to repair the bad parts.
    • Mesh creation - Hexahedral, tetrahedral and prism meshers.
    • Mesh editing - mesh diagnostics, mesh editing and smoothing.
    • Solution - set up solution for a range of solvers, including CFX.
    • View manager - to measure distances, angles, changing views.
    • Tree - to manage the parts, assemblies and their behaviours It is also a flexible and customisable post-processor that interfaces with all the major CFD solvers.
  • ANSYS Fluent, which contains the broad physical modeling capabilities needed to model flow, turbulence, heat transfer, and reactions for industrial applications.
  • ANSYS Workbench, which provides a schematic view of a project and includes geometry and meshing tools.

Although the interactive mode of CFX-Post is not fully available on this service - see the Known Problems & Limitations section of this help page - it can execute post-processing session files in batch mode to quickly reproduce output for a series of runs. It can also provide flexible and accurate quantitative post-processing of CFX results using the CFX Expression language.

Accessing the software

The interactive elements of the Ansys suite of programs is only made available on this service for pre- and post-processing; any computational work must be carried out in the batch system, not run directly from the graphical interface. Running computational work on a logon node can lead to poor interactive response for all users and IT Services reserve the right to kill any processes that are causing problems for the overall service.

The CFX Launcher does not request a license and hence will run on any logon node, as will the initial interface for the CFX Solver Manager and Workbench, but an error will be given when a license is requested. See also the Known Problems & Limitations section for issues with CFX-Pre and CFX-Post.

To load the module:

$ module load ANSYS/19.2

An example command to include in your job script:

 cfx5solve -def <def_file>

Example: CFX Serial Batch Job

An example can be found at ${BB_EXAMPLES}/ansys/cfx-serial/sbatch.sh. The example can be copied to a test directory and submitted to the batch system using sbatch.

$ cp -r ${BB_EXAMPLES}/ansys/cfx-serial ~/ansys-serial-test
$ cd ~/ansys-serial-test

Edit the sbatch.sh script according to your needs, then do:

$ sbatch sbatch.sh

Example: CFX Parallel Batch Job

An example can be found at ${BB_EXAMPLES}/ansys/cfx-parallel/sbatch.sh. The example can be copied to a test directory and submitted to the batch system using sbatch.

For parallel jobs CFX needs to know the nodes that the job is running on and how many cores are in use on each node. The nodes are selected by the scheduling system when the job runs and so cannot be defined when the job is submitted. This means that you will need to utilise environment variables such as SLURM_NTASKS and SLURM_JOB_NUM_NODES in order to inform CFX of the number of cores and nodes (respectively). We have provided a script called make_nodelist which creates a list of nodes for CFX to read. You need to load the slurm-helpers module in order to make this script easily accessible. See the example below.

$ cp -r ${BB_EXAMPLES}/ansys/cfx-parallel ~/ansys-parallel-test
$ cd ~/ansys-parallel-test

Edit the sbatch.sh script according to your needs, then do:

$ sbatch sbatch.sh

In some cases CFX parallel MPI jobs fail. If this happens to you try adding:

unset SLURM_GTIDS

to your batch submission script. (Source: https://www.cfd-online.com/Forums/cfx/161036-error-while-running-cfx-parallel-configuration.html).

Example: Fluent Batch Job

An example can be found at ${BB_EXAMPLES}/ansys/fluent/sbatch.sh. The example can be copied to a test directory and submitted to the batch system using sbatch.

For parallel jobs fluent needs to know the nodes that the job is running on and how many cores are in use on each node. The nodes are selected by the scheduling system when the job runs and so cannot be defined when the job is submitted. This means that you will need to utilise environment variables such as SLURM_NTASKS and SLURM_JOB_NUM_NODES in order to inform fluent of the number of cores and nodes (respectively). We have provided a script called make_nodefile which creates a list of nodes in a file for fluent to read. You need to load the slurm-helpers module in order to make this script easily accessible. See the example below.

$ cp -r ${BB_EXAMPLES}/ansys/fluent ~/ansys-fluent-test
$ cd ~/ansys-fluent-test

Edit the sbatch.sh script according to your needs, then do:

$ sbatch sbatch.sh

Interactive Usage

Interactive Use of CFX and ICEMCFD

The graphics displays in CFX_Pre and CFD_POST are not compatible with the Exceed X server and so are not available from this service; this has been raised with the suppliers but they do not support display to remote graphics terminals such as a PC with Exceed.

Use the command:

$ cfx5

to run the interactive front-end to CFX. The example session files are available in the directory specified by the CFX_EXAMPLES environment variable.

The full manuals in PDF format are available by running the command:

$ cfx5help

To run ICEM CFD use the command:

$ icemcfd

Solver runs requiring significant resources, including multiple cores, must be run using the batch system; such jobs may not be able to be run from within the cfx graphical interface. See the following sections for help on using the batch system.

Ansys Workbench

To run the Ansys Workbench, run the command:

$ runwb2

Accessing Previous Versions

Wherever possible, previous versions of this application will be retained for continuity, especially for research projects that require a consistent version of the software throughout the project. Such versions, however, may be unsupported by IT Services or the applications vendor, and may be withdrawn at short or no notice if they can no longer run on the cluster - for example, essential operating system upgrades may be incompatible with old versions.

Previous versions of this application are recorded below:

Known Problems & Limitations

Other Information

The support level for this software is P2.

New features in this release.

The Ansys web page has more information about the products and the company.

The Ansys student portal is freely available and has a link to a freely-downloadable Windows 64-bit student edition of Ansys which is only limited by the size of problem that can be solved. There is also a link to self-guided technical support. The support includes installation videos, an FAQ for troubleshooting help and several introductory tutorials that show how to perform basic simulations. Please note that Ansys do not provide online or face-to-face technical support for this free product.

Students and members of staff who do not hold their own license are urged to register for the Ansys Customer Portal which includes documentation, training materials, tutorials and a searchable knowledge base. To access this, go to the Ansys Customer Portal and select the Student Registration link in the Not yet a member option in the Log In section. quoting:

  • Account Number (Customer Number): 313381
  • Academic Facility Name: University of Birmingham

on the registration page. Both items must be entered exactly as shown above - for example, specifying The University of Birmingham as the Facility will give an error. During registration there is a drop-down list of professors, one of which must be selected to complete the registration - students should select their supervisor if this is one of the options. If none of the names are recognised select Hatton, Paul in IT Services. You are then asked to create a password after which you can then access the Customer Portal using these credentials.

 


Last modified: 20 March 2018