OpenFOAM® v2.0.0: Post-Processing

OpenFOAM® v2.0.0: Post-Processing

16th June 2011

Function Objects

OpenFOAM can carry out post-processing (and run-time control) automatically while the simulation is running using function objects. In v2.0.0, the range of available functionality has been extended to include the following:

  • abortCalculation - Watches for presence of the named file in the case directory and aborts the calculation if it is present.
  • coded - See Run-time Control: Code Compilation
  • fieldValue - faceSource extended to integrals (e.g. mass flux) over any sampleSurface, e.g. triSurfaceMesh.
  • nearWallFields - generates a volField with boundary values from interpolated internal field, at a given distance from the wall.
  • partialWrite - allows registered objects, e.g. fields, to be written at different times (frequencies).
  • streamLine - generates streamlines in one of the sample formats.
  • timeActivatedFileUpdate - modifies case settings at specified times in a simulation.
  • writeRegisteredObject - writes registered objects, e.g. fields that are not scheduled to be written in the application, i.e. created with NO_WRITE.

Below is an example of an image the elements of which are created from data files generated by function objects, rather than by post-processing the actual OpenFOAM solution data itself. The image includes streamlines, a cutting plane, coloured by velocity, and the motor bike surface, coloured by pressure.

Motorbike with sampled surface

Source code
fieldFunctionObjects library - $FOAM_SRC/postProcessing/functionObjects/field
IOFunctionObjects library - $FOAM_SRC/postProcessing/functionObjects/IO
jobControl library - $FOAM_SRC/postProcessing/functionObjects/jobControl
utilityFunctionObjects library - $FOAM_SRC/postProcessing/functionObjects/utilities
Examples
Example controlDict files in the source code, listed with the command:
find $FOAM_SRC/postProcessing -name controlDict
Examples in the tutorials, listed with the command:
find $FOAM_TUTORIALS -name controlDict | xargs grep -l functions

Other Changes to Post-Processing

Other new features and improvements in post-processing include the following.

  • Paraview and the foamToVTK utility now include full support for polyhedral cells.
  • The foamToEnsight utility supports parallel continuous data so that isosurfaces, etc., are continuous across processor boundaries, and includes a new -nodeValues option to generate and output nodal field data.
  • A new singleCellMesh utility converts a mesh and fields to a single cell mesh, so that only boundary data is preserved; useful for post-processing large cases.
  • A steadyParticleTracks utility generates VTK tracks from data for a particle cloud.
  • The sampling library includes a new ensight output format for surface sampling and a new patchInternalField sampling surface that operates like patch samples the internal field, instead of the boundary (patch) field.