Code_Aster
®
Version
7.4
Titrate:
Operator
ASSE_MAILLAGE
Date:
19/01/05
Author (S):
C. DURAND, J. PELLET
Key
:
U4.23.03-G
Page
:
1/4
Instruction manual
U4.2- booklet: Mesh
HT-66/05/004/A
Organization (S):
EDF-R & D/AMA
Instruction manual
U4.2- booklet: Mesh
Document: U4.23.03
Operator
ASSE_MAILLAGE
1 Goal
To assemble 2 mesh to form new.
The two mesh to be assembled can come from the operators:
LIRE_MAILLAGE
[U4.21.01],
DEFI_MAILLAGE
[U4.23.01],
ASSE_MAILLAGE
[U4.23.03],…
I.e. they can contain ordinary meshs and/or super-meshs carrying
macronutrients.
Product a structure of data of the mesh type.
Code_Aster
®
Version
7.4
Titrate:
Operator
ASSE_MAILLAGE
Date:
19/01/05
Author (S):
C. DURAND, J. PELLET
Key
:
U4.23.03-G
Page
:
2/4
Instruction manual
U4.2- booklet: Mesh
HT-66/05/004/A
2 Syntax
mac (mesh) = ASSE_MAILLAGE
(
% names of the 2 mesh to be assembled:
MAILLAGE_1
=
ma1
,
[mesh]
MAILLAGE_2
=
ma2
,
[mesh]
% “to restick” the 2 mesh
/
OPERATION
=
“JOINING”,
COLLAGE=_F (
GROUP_MA_1 = gma1, [gr_maille]
GROUP_MA_2 = gma2, [gr_maille]),
% “to superimpose” the 2 mesh
/
OPERATION
=
“SUPERIMPOSES”,
% to assemble mesh containing of
% macronutrients (substructures)
/
OPERATION
=
“SOUS_STR”,
)
Code_Aster
®
Version
7.4
Titrate:
Operator
ASSE_MAILLAGE
Date:
19/01/05
Author (S):
C. DURAND, J. PELLET
Key
:
U4.23.03-G
Page
:
3/4
Instruction manual
U4.2- booklet: Mesh
HT-66/05/004/A
3 Operands
MAILLAGE_1
and
MAILLAGE_2
MAILLAGE_1 = ma1, MAILLAGE_2 = ma2,
ma1
and
ma2
are the names of the 2 mesh to be assembled.
4 Operation
=
“SUPERIMPOSES”
With this choice:
“SUPERIMPOSES”
, all the entities (meshs, nodes, group_ma and group_no) of
2 mesh is preserved. The only problem to be regulated relates to the name as of the these entities (conflict of
names possible because the 2 mesh can contain, for example, of the of the same nodes name).
To solve these possible problems of names:
· The nodes and the meshs are always famous. That wants to say that the user cannot
to know the name of the nodes and meshs of the mesh result. It will have in general to use (it
who is always advised) the names of group_no and group_ma. Or it will have to print it
mesh to know the selected names.
· The names of the group_no and group_ma are preserved within the limit of the possible one. If 2
group_ma (or 2 group_no) has the same name in the 2 mesh, the group coming from 2nd
mesh is famous automatically and the renaming is indicated in the file
of message.
5 Operation
=
“JOINING”
The operation
“JOINING”
is used to connect 2 mesh which would have been with a grid independently in
2 distinct files (for example by 2 different teams).
If the 2 mesh is not coherent on their interface (different discretization), the user will not have
not other choice to use the functionality
AFFE_CHAR_XXX/LIAISON_MAILLE
“to bind” them
degrees of freedom of the 2 mesh which will remain topologically disjoined. It will have to then use
the operation
“SUPERIMPOSES”
.
If on the other hand, the 2 mesh were envisaged to be restuck, it will use the operation
“JOINING”
.
For that, it will have to take the precaution to name the 2 groups of meshs (of interface) which
will allow to restick the 2 mesh. Moreover these 2 groups of meshs must be
geometrically coincidents. The user will write then:
OPERATION=' COLLAGE', COLLAGE=_F (GROUP_MA_1=' GMA1', GROUP_MA_2=' GMA2',),
The group_ma gma1 and gma2 will then be amalgamated. More precisely:
· the meshs of gma1 and gma2 will be removed
· the nodes of gma2 will subisteront (but will be orphan)
· the nodes of gma1 will connect the 2 mesh.
Before “amalgamating” the 2 group_ma gma1 and gma2, the program will check that the nodes of these
2 group_ma are well coincidents (with a tolerance of 0.001 times the length of the smallest edge
of the 2 mesh).
The conflicts of names of the entities of the 2 mesh are regulated in the same way that for the operation
“SUPERIMPOSES”
(see above).
Code_Aster
®
Version
7.4
Titrate:
Operator
ASSE_MAILLAGE
Date:
19/01/05
Author (S):
C. DURAND, J. PELLET
Key
:
U4.23.03-G
Page
:
4/4
Instruction manual
U4.2- booklet: Mesh
HT-66/05/004/A
6 Operation
=
“SOUS_STR”
To mix in the same model of the ordinary finite elements and macronutrients (or under
structures), it is necessary to have a mesh containing at the same time ordinary meshs and
(super) meshs. The operator
ASSE_CHAMP
/
OPERATION = “SOUS_STR”
allows to constitute it
“mixed” mesh by assembling a mesh ordinary (or mixed) and a mesh containing of
(super) meshs (coming from
DEFI_MAILLAGE
).
The direction of the assembly is as follows:
·
All entities of the 2 mesh arguments
ma1
and
ma2
(meshs, super-meshs, nodes,
group meshs and groups nodes) are recopied in the mesh result:
mac
.
·
The only shared entities are the nodes same names. These are the nodes which
allow to assemble the 2 mesh.
·
Processing of the entities bearing the same name:
-
nodes: nodes of the second mesh bearing an existing name in the first
mesh, are not added: it is supposed that they are the same ones. Co-ordinates of
preserved node are those of the node of the first mesh. An alarm is emitted when
the distance between the two confused nodes is higher than:
10
6
-
.d_ refe
where
d_ refe
is a length characteristic of the mesh:
(
)
(
)
d_ refe
D O NR
max,
=
where
(
)
D O NR
,
is the distance from the node
NR
at the origin of the total reference mark.
-
meshs (or super-meshs): if mesh
ma2
of the same meshs name contains than
meshs of the first mesh
ma1
, the program stops in fatal error.
-
group meshs (or groups of nodes): if mesh
ma2
a group contains of
of the same meshs name than a group of
net
ma1
, the aforementioned is ignored and it
program transmits a message of alarm.
7 Examples
7.1 ex2
One wants to create a mesh (
matot
) containing static substructures and an ordinary mesh.
ma1
= LIRE_MAILLAGE ()
macro1 =
MACR_ELEM_STAT (...)
macro2 =
MACR_ELEM_STAT (...)
masss = DEFI_MAILLAGE (DEFI_MAILLE = _F (MACR_ELEM_STAT = macro1…))
matot = ASSE_MAILLAGE (OPERATION=' SOUS_STR',
MAILLAGE_1 = ma1, MAILLAGE_2 = masss)