4. Examples#
4.1. Entire crack defined by various types of entities in 3D#
The crack bottom is defined by a group of elements, the upper lip by a list of cells, the lower lip by a list of mesh groups.
FOND_FISS = _F (GROUP_NO = (“GMFOND”), LEVRE_SUP = _F (GROUP_MA =( “GM123”),), LEVRE_INF = _F (GROUP_MA = (“GRM1”, “GRM2”),), )
with the following groups defined in the ma mesh:
GRN3: {N017 N015} GRM123: {MA5, MA13, MA4, MA12} GRM1: {MA17 MA15 MA6} GRM2: {MA40}
The crack bottom here consists of the group of elements GMFOND connecting the nodes N010, N018, N016, N017, N015 in an orderly manner.
4.2. Using operand NORMALE (plane crack DECOLLEE in 3D)#
FOND_FISS =_F (GROUP_NO =” GMFOND “, CONFIG_INIT =” DECOLLEE “, NORMALE = (0.,0., -1. ), )
Normal \(\text{N}\) is defined at the plane of the crack.
The direction \(\text{n}\) of the normal to the crack bottom in the plane of the crack lips is determined by \(\text{n}={\text{Γ}}_{\text{0}}\wedge \text{N}\).
4.3. 2D crack#
The crack bottom is defined by the N10 node of the ma mesh. This knot is the only node in group GN10 The lip-stitch groups are noted GMSUP and GMINF respectively. The crack can be defined either from the normal:
FOND_FISS = _F (GROUP_NO = “GN10”), CONFIG_INIT = “DECOLLEE”, NORMALE = (-1.,1.,0. ), )
or from the mesh of the lips:
fiss = DEFI_FOND_FISS (MAILLAGE = my,
FOND_FISS = _F (GROUP_NO = “GN10”), LEVRE_SUP = “GMSUP”, LEVRE_INF = “GMINF”,
)
4.4. Closed crack bottom with node ordering#
GROUP_MA =” GMA “, GROUP_NO_ORIG = “NO”, GROUP_MA_ORIG = “GMA2”), CONFIG_INIT = “DECOLLEE”, NORMALE = (0.,0., -1. ), )
with GMA: {MA1, MA2, MA3,…},…}, GMA2: {MA2}
Normal \(\text{N}\) is defined at the plane of the crack. The direction \(\text{n}\) of the normal to the crack bottom in the plane of the crack lips is determined by \(\text{n}={\text{Γ}}_{\text{0}}\wedge \text{N}\).
The order in which the cells are declared in the list is not important. The operator verifies that the NO node does indeed belong to mesh MA2 and that all the segment cells provided do indeed form a closed connected curve. The order of the nodes in the product concept will be that given by the arrow in the drawing below, starting from NO.
