extract_surface command¶

Syntax¶

extract_surface inputfile file surfacefile extrusionfile extrude_length l min_rad r mode

• inputfile = filename of VTK grid data

• file = obligatory keyword

• surfacefile = filename to write surface VTK data

• optional extrusion args

  extrusionfile = filename to write extruded surface VTK data
  extrude_length = obligatory keyword
  l = total height of extruded volume
  min_rad = obligatory keyword
  r = distance volume is extruded outwards
  

• mode = output file mode ascii or binary (optional)

Examples¶

extract_surface data/grid.vtk file data/surface.vtk data/extrusion.vtk extrude_length 0.1 min_rad 0.025

Description¶

Given an unstructured grid VTK file consisting of hexahedral cells, this command will extract and triangulate the surface and save it to an unstructured grid VTK file adding a unique ID for each cell face (i.e. typically two triangles). Furthermore, the surface thus obtained may be used to create a shell geometry extruding the surface l-r distance units inwards and r distance units outwards. If used as insertion volume for multi-level coarse-grain simulations, r should be set to the minimum particle radius occuring in the simulation. The total extrusion length l should be about 2 particle diameters but is ultimately determined by the insertion rate and the velocity of the particles.

Restrictions¶

none

Default¶

mode = ascii