4. C modeling

4.1. Characteristics of C modeling

The third cut we are testing again corresponds to a case where two of the edges of TETRA10 see the lsn cancel out exactly twice, at one of their ends and at their midpoint. An example of this configuration is shown in Figure.

Figure 4.1-a : representation of the C modeling cuta

For cutting, we come back to the more classical case represented in Figure, whose subtetrahedron cutting is detailed in [R7.02.12].

Figure 4.1-b : : corresponding healthy configuration

4.2. Characteristics of the mesh

To « find yourself » in this cutting configuration, the lsn is chosen spherical, with a center C (\(-\frac{4}{3}\), \(-\frac{4}{3}\), \(-\frac{5}{6}\)) and with a radius \(R=\frac{\sqrt{(249)}}{6}\)

The edges of TETRA are then intersected by the level set at the following 5 points:

Intersection point	Coordinates
IP1	(1,0,0)
IP2	(0.5,0,0.5)
IP3	(0,0.5,0.5)
IP4	(0, \(\frac{2\ast \sqrt{(10)}-4}{3}\) ,0)
IP5	(\(\frac{2\ast \sqrt{(10)}-4}{3}\) ,0,0)

4.3. Tested sizes and results

After executing command MODI_MODELE_XFEM, we check that the 5 intersection points IP1, IP2,, IP3, IP4 and IP5 are in the group NFISSU and that their position is correct.

Quantities tested	Reference type	Reference value	Tolerance
COORX IP1	“ANALYTIQUE”	0.0	10E-06
COORY IP1	“ANALYTIQUE”	0.0	10E-06
COORZ IP1	“ANALYTIQUE”	1.0	10E-06
COORX IP2	“ANALYTIQUE”	0.5	10E-06
COORY IP2	“ANALYTIQUE”	0.0	10E-06
COORZ IP2	“ANALYTIQUE”	0.5	10E-06
COORX IP3	“ANALYTIQUE”	0.0	10E-06
COORY IP3	“ANALYTIQUE”	0.5	10E-06
COORZ IP3	“ANALYTIQUE”	0.5	10E-06
COORX IP4	“ANALYTIQUE”	0.0	10E-06
COORY IP4	“ANALYTIQUE”	0.77485177	10E-06
COORZ IP4	“ANALYTIQUE”	0.0	10E-06
COORX IP5	“ANALYTIQUE”	0.77485177	10E-06
COORY IP5	“ANALYTIQUE”	0.0	10E-06
COORZ IP5	“ANALYTIQUE”	0.0	10E-06

The cut mesh (Figure) was also post-processed using SALOME. The cut obtained is in accordance with expectations, with 6 subtetrahedra that are consistent with the discontinuity.

Figure 4.3-a : C modeling cutting configuration