Xfem manager record and associated records

This record specifies the number of enrichment items and simulation options common for all enrichment items. Functions used for enrichment (e.g. Heaviside, abs or branch functions) are not specified here, they are specified for each enrichment item separately. The same holds for the geometrical representation of each enrichment item (e.g. a polygon line or a circle). Currently, OOFEM supports XFEM simulations of cracks and material interfaces in 2D. The input format for the XFEM manager is:
XfemManager numberofenrichmentitems #(in)
numberofgppertri #(in)
debugvtk #(in)
vtkexport #(in)
exportfields #(in)

where numberofenrichmentitems represents number of enrichment items, numberofgppertri denotes the number of Gauss points in each subtriangle of a cut element (default 12) and debugvtk controls if additional debug vtk files should be written (1 activates the option, 0 is default).

The specification of an enrichment item may consist of several lines, see e.g. the test sm/xFemCrackValBranch.in. First, the enrichment item type is specified together with some optional parameters according to
*EntType (num#)(in)
enrichmentfront #(in)
propagationlaw #(in)

where enrichmentfront specifies an enrichment front (we may for example employ branch functions at a crack tip and Heaviside enrichment along the rest of the crack, hence the ``front'' of the enrichment is treated separately) and propagationlaw specifies a rule for crack propagation (this feature is still highly experimental though). Specification of an enrichmentfront and a propagationlaw is optional.

The next line specifies the enrichment function to be used:
*EntType (num#)(in)

This is followed by a line specifying the geometric description (e.g. a polygon line or a circle) according to
*EntType (num#)(in) extra attributes

where the number and type of extra attributes to specify will vary depending on the geometry chosen, e.g. center and radius for a circle or a number of points for a polygon line.

If an enrichment front was specified previously, the type and properties of the enrichment front are specified on the next line according to
*EntType (num#)(in) extra attributes

If a propagation law was specified previously, it's type and properties are also specified on a separate line according to
*EntType (num#)(in) extra attributes

Borek Patzak