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Revision as of 13:51, 18 August 2015 by A Saramet (talk | contribs) (Improving parallel run performance)
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1 OpenFOAM


Module:        cae/openfoam/'version'
Target System: Red-Hat-Enterprise-Linux-Server-release-6.4-Santiago 
Main Location: /opt/bwhpc/common
Priority:      mandatory
License:       GPL

1.1 Accessing and basic usage

The OpenFOAM® (Open Field Operation and Manipulation) CFD Toolbox is a free, open source CFD software package with an extensive range of features to solve anything from complex fluid flows involving chemical reactions, turbulence and heat transfer, to solid dynamics and electromagnetics.

In order to check what OpenFOAM versions are installed on the system, run the following command:

$ module avail cae/openfoam

Typically, several OpenFOAM versions might be available.

Any available version can be accessed by loading the appropriate module:

$ module load cae/openfoam/<version>

with <version> specifying the desired version.

To activate the OpenFOAM applications, after the module is loaded, run the following:

$ source $FOAM_INIT

or simply:

$ foamInit

1.2 Improving parallel run performance

To improve the concurrently solving process and decrease the error occurrence probability while running an OpenFOAM job in parallel (on a singlenode), some modifications have been introduced. Specifically, after the case decomposition is done, it is recommended to save the decomposed data directly on the nodes in the pre-allocated work-space and use it from there. When the calculations are over, the data is moved back to the case folder and reconstructed. It will improve the overall performance, considering that you allocated enough wall-time to decompose and rebuild your cases, as it moves theprocessor*folders to and out of the nodes local work-space. For such a procedure it is necessary to use the following commands for decomposition and reconstruction of the geometry domain:

$ decomposeParHPC
$ reconstructParHPC
$ reconstructParMeshHPC

instead of:

$ decomposPar
$ reconstructPar
$ recontructParMesh

For example, if you want to runsnappyHexMeshin parallel, you may use the following commands:

$ decomposeParMeshHPC
$ mpiexec snappyHexMesh -overwrite
$ reconstructParMeshHPC -constant

instead of:

$ decomposePar
$ mpiexec snappyHexMesh -overwrite
$ reconstructParMesh -constant

2 Submitting an OpenFOAM batch job