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Pre/Post-Processing
**********************

Files:

* configure files: ``.cfg``
* mesh files: ``.su2``

The ``.su2`` file format is defined as follows:

* line 3: The value "5" is triangle element type.
* line 17: The value "3" is line element type.
 
::

   NDIME= 2
   NELEM= 10216
   5	417	69	311	0
   5	302	55	56	1
   .....
   5	5134	5106	5097	10214
   5	5122	5109	5075	10215
   NPOIN= 5233
   9.997500181200000e-01	-3.632896519016437e-05	0
   9.990000128750000e-01	-1.452537504052920e-04	1
   .....
   1.141681957531808e+01	1.405512047239916e+01	5231
   1.719315911158019e+01	7.913059239332790e+00	5232
   NMARK= 2
   MARKER_TAG= airfoil
   MARKER_ELEMS= 200
   3	199	0
   3	0	1
   .....
   3	197	198
   3	198	199
   MARKER_TAG= farfield
   MARKER_ELEMS= 50
   3	200	201
   3	201	202
   .....
   3	248	249
   3	249	200

To generate mesh files in ``.su2`` format using Gmsh: ::

  cd FENGSim/starter/su2/quickstart
  gmsh test.geo -2 -format msh -save_all
  gmsh test.msh -refine -smooth 10 -save_all -format su2
  mpirun -np 4 ./../../../toolkit/CFD/install/su2/bin/SU2_CFD test.cfg
  paraview flow.vtu