General (multi-faceted) body and Tetrahedral meshing

General (multi-faceted) body and Tetrahedral meshing

The most significant developments of FEMGV 6 are the inclusion of general bodies and the ability to create a tetrahedral mesh. This allows multi-faceted bodies to be created and then meshed with tetrahedral elements, resulting in reduced model generation time.

The command for a general body is as follows:

GEOMETRY BODY GENERAL Bname OuterSet InnerSet1 InnerSet2 etc...

where

‘Bname’ is the name of the body to be created,

‘OuterSet’ is a set containing surfaces that represent the outer boundary, and

‘InnerSetn’ is a set containing surfaces that represent the nth cavity.

[helda.gif]

Figure 5: Example of a model containing general bodies meshed with tetrahedral elements.

Each set of surfaces should constitute a single closed shell (i.e., each line is contained in 2 and only 2 surfaces).

General body pre-check:-

Command: MESHING OPTIONS CHECK GBODY ON/OFF.

This command enables/disables the general body pre-check facility. A general body that is created subsequent to this command being selected, will have the definition of its underlying surfaces scrutinised and, if necessary, redefined such that the surfaces have meshing attributes consistent with the algorithm attached to the general body.

Note that the general body pre-check can also be set using the resource:

Femsys.*.MESH.CHK_GBODY : True/False

The default is True.