CoreGen Input File Keyword Definitions
1. Geometry: Surface or volume core models can be generated; if unspecified, the default is to generate a volume model.
2. GeometryType: The GeometryType is specified as rectangular, hexflat, or hexvertex (see section 2 of this paperÂ for a description of the hexagonal lattice types).
3. GeomEngine: This keyword typically takes the ‘OCC’. Note, specified engine type matches with geometric engine used for building ‘iGeom’. The o/p geometry file has an extension of ‘.stp’ with ‘OCC’ or ‘.facet’ with ‘Facet’ engines.
4. Extrude: When using this keyword, the ‘Geometry’ must be ‘surface. The next two keywords define the height of the model in Z-direction and the number of divisions in Z-direction.
5. Assemblies: This keyword specifies the number of different assembly types, and the pitch of the lattice arrangement (two values for a rectangular lattice, and one for a hexagonal lattice).
6. <mesh_file>: For each assembly type, a file name containing the mesh for that assembly type and the alias used to reference that assembly type appear on a separate line.
7. Lattice: The number of assemblies in the X and Y directions (GeometryType: Rectangular) or the number of rings (GeometryType: Hexflat or Hexvertex) in the core.
8. <assy_alias>: Assembly aliases are listed in order of appearance in the core lattice of the specified type, as described in Section 2.2. Note the number of assemblies in a given core depends on the lattice type and the parameters specified with the Lattice keyword. Assembly aliases in the lattice should all appear on one line. Line continuation characters â&â can be used to break lines in the file, to make the input file easier to read.
9. MergeTolerance: This is the tolerance value used for merging the nodes of assembly meshes.
10. NeumannSet: It can take values ‘top’, ‘bot’ ‘side’ or ‘sideall’. This keyword is used to create top, bottom and side surface sidesets for the entire core model. When using ‘side’ keyword equation of the plane (XY plane, since Z direction is along the height – always) ax + by + c.Â For the example below NeumannSet 101 will be created on a plane along the line specified by x + 11.75 = 0
NeumannSetÂ Â TopÂ Â 99
NeumannSetÂ Â SideAll Â 100
NeumannSetÂ Â Side Â 101Â Â xÂ Â 1 Â y Â 0 Â cÂ Â 11.75
11. OutputFileName: OutputFileName with extension can be set using this keyword. If not specified, o/p file name is <coregen_input_file>.h5m
12. Background: If specified, this keyword specifies an assembly mesh that fills interstices regions between assemblies, along with any structure surrounding the core, such as core barrel or reactor vessel.
13. End: This command marks the end of CoreGen input file.
14. ProblemType: Copy/move operations can be performed on ‘Mesh’ or ‘Geometry’. Default value of this keyword is ‘Mesh’. When using geometry files in ‘Assemblies’ keyword this keyword should be setup to copy/move geometry.
15. SaveParallel: When using parallel-capable CoreGen. This keywords offer enables option for saving mesh file.
Takes values ‘Multiple’, ‘Both’ and ‘One
ONE: one file per processor
MULTIPLE: one file per processor and one combined file
ONE: one combined file (Default)
16. INFO: It takes arguments ON or OFF. This dumps a .csv file with centroid’s of assembly locations.
17. MeshINFO: On or Off. This dumps a file with coordinates of centroids of all the elements, followed by the pin and assembly number corresponding to this element.
18. Symmetry:Â Takes in an integer. For rectangular assemblies it is 1. For hexagonal assemblies it can take values 6 (1/6 core) , 12 (1/12th core) and 1 (full core). This keyword sets the array sizes for assemblies specified using the “Lattice” keyword.