COMSOL

Comsol Multiphysics is a finite element analyzer, solver, and simulation code. There are a limited number of licenses available for COMSOL features on Joule 3.0. The status of the license can be checked using:

comstat

This command can be run from any login node. The most important output of this command is the comsol and comsolgui features which are required to launch any graphical instance of COMSOL.

COMSOL Graphical User Interface

COMSOL Multiphysics is usually run in graphical mode. To launch an interactive session, open a terminal inside a Cap Client GUI Session and use the salloc command as demonstrated here:

login:~> salloc --x11 -N1 -p general
salloc: Granted job allocation 1234567
salloc: Waiting for resource configuration
salloc: Nodes n0001 are ready for your job
n0001:~> module load comsol/6.2
n0001:~> comsol

This will cause a COMSOL window to appear in the CAP Client GUI Session. COMSOL can then be stopped by exiting the COMSOL GUI and typing “exit” at the session terminal. 

Running COMSOL in Parallel

To run COMSOL in parallel non-interactive mode, copy the run_comsol_6.2_parallel submission script from /nfs/apps/Submission/ to the current working directory. The following lines in the script will then need to be updated:

-inputfile test-alpha-finer-wavguide-mesh.mph \
-outputfile out.mph

The “-inputfile” flag should be changed to the name of the input file for the job submission. An appropriate output filename should be selected for the “- outputfile” flag.

For most job submissions, it is recommended to use:

#SBATCH –nodes=1

It was found that using one node produced the fastest completion times on most test jobs. 

After the appropriate changes have been made to the script, the job can be submitted to the queuing system with:

sbatch  run_comsol_6.2_parallel

The job will launch when the requested resources are available in the queuing system.