Code_Aster ®
Version
7.4
Titrate:
Operator DEFI_MAILLAGE


Date:
31/01/05
Author (S):
J. Key PELLET
:
U4.23.01-G Page
: 1/10

Organization (S): EDF-R & D/AMA
Handbook of Utilization
U4.2- booklet: Grid
Document: U4.23.01

Operator DEFI_MAILLAGE

1 Goal

To define a grid using macronutrients for calculations of static under-structuring.

This command makes it possible to define a new grid starting from macronutrients produced by
operator MACR_ELEM_STAT [U4.62.01]. This new grid (containing only the supports
geometrical of the macronutrients) can then “be assembled” with another grid (containing by
example of the “traditional” meshs thanks to command ASSE_MAILLAGE [U4.23.03] and the clean option
with the under-structuring.

Product a structure of data of the grid type.

Handbook of Utilization
U4.2- booklet: Grid
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator DEFI_MAILLAGE


Date:
31/01/05
Author (S):
J. Key PELLET
:
U4.23.01-G Page
: 2/10

2 Syntax

my (grid) = DEFI_MAILLAGE (


DEFI_MAILLE
=
(_F (


MACR_ELEM_STAT
=
l_se


,
[l_macr_elem_stat]


MAILLE
=
l_mail
,
[l_maille]


| TRAN
=/(X, y), or (X, y, Z), [l_R]
/
(0., 0.)
or
(0., 0., 0.),
[DEFAUT]



| ANGL_NAUT
=/(), or (,),
[l_R]
/
(0.),
or
(0., 0., 0.), [DEFAUT]




CENTER
=/(px, py)
or
(px, py, pz),
[l_R]
/
(0., 0.),
or
(0., 0., 0.),
[DEFAUT]
),),

| RECO_GLOBAL =
(_F
(



/ALL = “YES”
,




/MAILLE
=
l_maille
,
[l_maille]



| CRITERION =/“ABSOLUTE”,
/
“RELATIF”
,
[DEFAUT]
|
PRECISION
=
/
prec,
[R]
/
1.D-3
,
[DEFAUT]








),),
|
RECO_MAILLE
=
(_F (




MAILLE
=
l_mail
,
[l_maille]




GROUP_NO
=
l_gno
,
[l_group_no]



/OPTION
= “GEOMETRIQUE”
,
[DEFAUT]





| CRITERION =/“ABSOLUTE”,
/
“RELATIF”
,
[DEFAUT]
|
PRECISION
=
/
prec,
[R]
/
1.D-3
,
[DEFAUT]
/
OPTION
=
“NOEUD_A_NOEUD”
,
/
OPTION
=
“INVERSE”
,
),),

DEFI_NOEUD
=
_F
(



/TOUT =

“OUI”,




PREFIXE
=
pref,
[KN]





INDEX


=
(DM, Fm, DNN, fn),
[l_I]



/
NOEUD_FIN

=
no_fin
,
[node]




MAILLE =
mall,



[mesh]





NOEUD_INIT
=
no_ini
,
[node]
),),

DEFI_GROUP_NO = _F (



//TOUT =
“OUI”,
/
MAILLE
=
mall,
[mesh]




PREFIXE


=
pref,
[KN]




INDEX =
(DM, Fm, DNN, fn),


[l_I]



/
GROUP_NO_FIN
=
gno_fin,
[group_no]





MAILLE
=
mall,
[mesh]





GROUP_NO_INIT=
gno_ini,
[group_no]
),),











)
Handbook of Utilization
U4.2- booklet: Grid
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator DEFI_MAILLAGE


Date:
31/01/05
Author (S):
J. Key PELLET
:
U4.23.01-G Page
: 3/10

3 General information

In the documentation of this command, one will speak about:

·
macronutrient: object of the macr_elem_stat type [U4.62.01],
·
super-mesh: geometrical entity supporting one macro_élément,
·
initial grid when one indicates the grid which was used to generate a macronutrient,
·
final grid to indicate the grid produced by this command.

By extension these adjectives initial/final will apply to the entities attached to the grids: node,
net, group of nodes.

Practically, to build the final grid:

·
one defines super-meshs while positioning in the space (2D or 3D) of the macronutrients
existing (same a macr_elem_stat can generate several super-meshs),
·
one resticks the super-meshs between them,
·
one re-elects, if it is wanted, certain nodes,
·
one creates, if it is wanted, certain groups of nodes.

Note:

One can note that the grid created by this command is made only of super-meshs.
One thus cannot (for example), to draw it with the usual post-processors.
possibilities of curing it will be able to exist with command DEFI_SQUELETTE [U4.24.01].
To mix finite elements “traditional” and substructures, it is necessary to use
the operator of “concatenation” of grids [U4.23.03]: mag = ASSE_MAILLAGE (
MAILLAGE= (m1, m2))

A grid resulting from operator DEFI_MAILLAGE contains:

·
super-meshs,
·
nodes,
·
groups of nodes.

The super-meshs are defined by translation/rotation of macronutrients.

As a “traditional” mesh, a super-mesh is entirely defined by the list of its nodes.
coordinated nodes of the meshs are those of the external nodes of the macronutrients
transforms by the geometrical transformation: translation, rotation…

If one does not carry out a sticking together (cf RECO_GLOBAL/RECO_MAILLE), the grid has as much of
nodes that the sum of the nodes of the super-meshs.

C1 convention:

When one “resticks” the super-meshs, one eliminates certain nodes. By convention, at the time of one
elimination of coinciding nodes, one preserves the node (and thus its co-ordinates) which comes from
first mesh of the list l_mail (cf RECO_GLOBAL/RECO_MAILLE).

As in any Aster grid, the nodes are named. By defect, the names of the nodes are
given by the program in the form: NOijklmn where ijklmn is a number ranging between 000001
and 999999.

Key words DEFI_NOEUD and DEFI_GROUP_NO make it possible the user to re-elect certain nodes
and to define groups of nodes.
Handbook of Utilization
U4.2- booklet: Grid
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator DEFI_MAILLAGE


Date:
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Author (S):
J. Key PELLET
:
U4.23.01-G Page
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4 Operands

4.1 Word
key
DEFI_MAILLE

DEFI_MAILLE =

This key word factor makes it possible to define the super-meshs of the grid using macr_elem_stat.

4.1.1 Operand
MACR_ELEM_STAT

MACR_ELEM_STAT = l_se

l_se is the list of the names of the macronutrients which will generate the meshs.

4.1.2 Operand
MAILLE

MAILLE = l_mail

l_mail is the list of the names which one wants to give to the meshs. This argument is optional. In sound
absence, one will give to the meshs the names macronutrients (this is obviously impossible
if one wants to use several times the same macronutrient).

4.1.3 Geometrical operands of transformations

| TRAN
=

This key word defines the translation to be applied to the macr_elem_stat:

·
if one is in 2D, one awaits 2 realities: (tx, ty),
·
if one is in 3D, one awaits 3 realities: (tx, ty, tz).

| ANGL_NAUT
=





CENTER =

These key words define rotation to be applied to the macr_elem_stat.

If one is in 2D, one awaits 3 realities:

·
is the angle (in degrees) of rotation in the plan for ANGL_NAUT,
·
px and py are the co-ordinates of the center of rotation for CENTER.

If one is in 3D, one awaits 6 realities:

·
, and are the nautical angles of rotation (in degrees). (Cf the operator
AFFE_CARA_ELEM [U4.42.01]) for ANGL_NAUT,
·
px, py and pz are the co-ordinates of the center of rotation for CENTER.

Important remark:

It is known that the key word order is not significant for Aster. The operation of
translation/rotation is conventionally made in the order rotation then
translation. These two operations do not commutate in general.
Handbook of Utilization
U4.2- booklet: Grid
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator DEFI_MAILLAGE


Date:
31/01/05
Author (S):
J. Key PELLET
:
U4.23.01-G Page
: 5/10

4.2 Word
key
RECO_GLOBAL

| RECO_GLOBAL
=

/ALL = “YES”,


/MAILLE = l_maille,

| CRITERION =/“ABSOLUTE”,







/
“RELATIF”
,
[DEFAUT]
|
PRECISION
=
/prec,







/
1.D-3,
[DEFAUT]

This key word makes it possible to restick a whole of super-meshs automatically
(indicated by key word MAILLE or key word TOUT) with a criterion of proximity
geometrical: 2 nodes of 2 different super-meshs m1 and m2 will be confused if
outdistance which separates them is:


<
prec

(CRITERE
=
“ABSOLU”),

<
prec * min (D (m1), D (m2))
(CRITERE
=
“RELATIF”).

where D (semi) note the smallest distance between 2 nodes of the semi super-mesh.

Note:

Two nodes of the same mesh will never be restuck.
If a mesh contains one node, it is necessary to use CRITERE = “ABSOLU”.

4.3 Word
key
RECO_MAILLE

RECO_MAILLE
=

This key word factor makes it possible to restick “with the hand” certain super-meshs indicated by
the user. The super-meshs which one can restick are those which were defined by the key word
DEFI_MAILLE.On then resticks the super-meshs via groups of nodes. To say what
one wants to restick it is thus necessary to give couples (mesh, group of nodes (of the initial grid)).

Note:

When one gives a couple (mesh, group of nodes), one indicates the list of the nodes of
group nodes which are external for the macr_elem_stat which defines the super-mesh.
It is in fact the intersection of the group of nodes and the edge of the substructure. This list is
ordinate as the initial group of nodes.
In theory, when one resticks 2 meshs via 2 groups of nodes, the whole of the nodes
indicated must restick itself (cf the convention chosen by key word OPTION). A message
of alarm will be emitted if it is not the case.

4.3.1 Operands
NET/GROUP_NO

MAILLE
=

One gives the list of the meshs here to be restuck. In general, one resticks meshs 2 by 2.

For the “corners”, it can be pleasant to restick all the convergent meshs in only once
(for example the 4 super-cubic ones which shares the same edge).

GROUP_NO
=

One gives here the list of the groups of nodes to be restuck. This list is of the same length than
list meshs.
Handbook of Utilization
U4.2- booklet: Grid
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator DEFI_MAILLAGE


Date:
31/01/05
Author (S):
J. Key PELLET
:
U4.23.01-G Page
: 6/10

4.3.2 Operand
OPTION

OPTION
=

This word makes it possible to choose the convention of sticking together of the lists of nodes defined by
groups of nodes.

·
“GEOMETRIQUE”:

The program will confuse the nodes by considerations of geometrical proximity.
(Cf key word: RECO_GLOBAL)

·
“OPPOSITE” “NOEUD_A_NOEUD”/:

That is to say: G1 = {A1, B1,}
C1
G2 = {A2, B2,
}
C2
G3 = {A3, B3,
}
C3



If OPTION = “NOEUD_A_NOEUD”, GROUP_NO = (G1, G2, G3)

one will restick:
A1 with
A2 with
A3
B1 with
B2 with
B3
C1 with C2 with C3



If OPTION = “OPPOSITE”

,
GROUP_NO = (G1, G2, G3)

one will restick: C1 with A2 with A3
B1 with
B2 with
B3
A1 with C2 with C3

Caution:

For option “INVERSE”, only the first group of nodes of the list of the GROUP_NO is
“turned over”.

4.4 Word
key
DEFI_NOEUD

DEFI_NOEUD
=

This key word factor makes it possible to re-elect whole or part of the nodes of the grid.

4.4.1 Operands
ALL/PREFIX/INDEX

|
ALL = “YES”,


PREFIXE = pref,


INDEX = (DM, Fm, DNN, fn),

These key words make it possible to re-elect all the nodes of the grid. The convention of
renaming is as follows (in pseudo FORTRAN):

no_fin (K8) = pref//no_mail (DM:Fm)//no_ini (DNN:fn)
Handbook of Utilization
U4.2- booklet: Grid
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator DEFI_MAILLAGE


Date:
31/01/05
Author (S):
J. Key PELLET
:
U4.23.01-G Page
: 7/10

What wants to say that the name of a node will be formed while concaténant:

·
the prefix possibly given by the user,
·
under-chains of characters extracted the name of the mesh which carries this node
(cf C1 convention of elimination of the nodes stated above [§ 3]). One
takes the characters of row ranging between DM and Fm. If DM > Fm, this
under-chains is empty,
·
under-chains of characters extracted the name of the node (in its grid
initial). One takes the characters of row ranging between DNN and fn. If DNN > fn,
this under-chain is empty.

It is necessary thus that: ltot = length (prefix) + (Fm-dm+1) + (fn-dn+1) 8

It is pointed out that 2 nodes cannot have the same name in the same grid. The goal
“play” for the user is to manage to re-elect certain nodes (without too many efforts of
its share) in a conventional way without this convention leading to names
identical.

A frequent case is as follows:

if the grids which gave rise to the macronutrients come from one
preprocessor which generates names of nodes of the NOijklmn form and if
the user gives to his super-meshs names with 2 characters: SA, SB,…. the sequence:

DEFI_NOEUD = _F (TOUT= “YES”, INDEX= (1, 2, 3, 8,))

will generate nodes of names: SA000001, SA000002,… , SB000001,

4.4.2 Operands
NOEUD_FIN/MESH/NOEUD_INIT

|
NOEUD_FIN
= no_fin,



MAILLE
=
mall,


NOEUD_INIT
=
no_ini,

These key words make it possible to re-elect nodes one by one:

·
no_fin is the name which one wants to give to the node grid that one creates
(final).
·
mall and no_ini identify the node to be re-elected: mall is the name of
super-mesh which carries the node, no_ini is the name of the node in the grid
who was used to create the macr_elem_stat which defined the super-mesh mall.

4.5 Word
key
DEFI_GROUP_NO

DEFI_GROUP_NO
=

This paragraph is almost identical to precedent (DEFI_NOEUD) by replacing word NOEUD_
by word GROUP_NO.

This key word factor makes it possible to define groups of nodes starting from groups existing in
initial grids of the macronutrients.

Note:

An initial group of nodes can contain nodes which do not belong to the edges of
macronutrients. These internal nodes thus do not exist in the final grid. By
convenience, one takes convention nevertheless to create the group reduced to its intersection
with the edge of the macronutrient.
Handbook of Utilization
U4.2- booklet: Grid
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator DEFI_MAILLAGE


Date:
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Author (S):
J. Key PELLET
:
U4.23.01-G Page
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4.5.1 Operands
ALL/MESH/PREFIX/INDEX

|
/ALL = “YES”,



/MAILLE = mall,


PREFIXE = pref,


INDEX = (DM, Fm, DNN, fn),

These key words make it possible to create all the groups of nodes corresponding to
groups of the initial grid associated the mesh mall or all the meshs if:

TOUT= “YES”.

The convention of renaming is as follows (in pseudo FORTRAN):

gno_fin (k8) = pref//no_mail (DM:Fm)//gno_ini (DNN:fn)

What wants to say that the name of a group of nodes will be formed while concaténant:

·
the prefix possibly given by the user,
·
under-chains of characters extracted the name of the mesh,
·
under-chains of characters extracted the name of the group_no of the initial grid.

It is necessary thus that:

ltot= length (prefix) + (Fm-dm+1) + (fn-dn+1) 8

A frequent case is as follows
: the grids which gave rise to
macronutrients come from a preprocessor which generates names of the form
GRNOijkl. If the user gives to his super-meshs names with 2 characters: SA,
SB,…., the sequence:

DEFI_GROUP_NO=_F (TOUT= “YES”, PREFIXE=' GN', INDEX= (1,2,5,8))

Will generate groups of nodes of names:

GNSA0001, GNSA0002,… , GNSB0001.

4.5.2 Operands
GROUP_NO_FIN/MESH/GROUP_NO_INIT

|
GROUP_NO_FIN = gno_fin,


MAILLE = mall,


GROUP_NO_INIT
= gno_ini,

These key words make it possible to create groups of nodes one by one:

·
gno_fin is the name which one wants to give to the GROUP_NO,
·
mall and gno_ini identify the initial GROUP_NO:
-
mall is the name of the super-mesh which carries the GROUP_NO,
-
gno_ini is the name of the GROUP_NO of the initial grid.
Handbook of Utilization
U4.2- booklet: Grid
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator DEFI_MAILLAGE


Date:
31/01/05
Author (S):
J. Key PELLET
:
U4.23.01-G Page
: 9/10

5 Example

That is to say the grid m1:

N9
N8
N7
E
D
N10
N6
grma1
N5 N19 N18
F
N11
N17
C
N4
N12
N16
grma2
N15
N1
N2
N3
N13
N14
With
B
G
3


GROUP_NO
: GROUP_MA
:

AB
=
(N1
N2
N3)
grma1
BC
=
(N3
N4
N5)
grma2

CD = .....
......

On this grid m1 one defines 2 macr_elem_stat.

mo1 = AFFE_MODELE
(AFFE = _F (GROUP_MA = GRMA1)…)
mo2 = AFFE_MODELE
(AFFE = _F (GROUP_MA = GRMA2)…)

S1 =
MACR_ELEM_STAT
(DEFINITION = _F (MODEL = MO1…)

EXTERIEUR

=
_F
(GROUP_NO
=
(AB, BC, CD, OF, EA))

…)
S2 =
MACR_ELEM_STAT
(DEFINITION = _F (MODEL = MO2…)

EXTERIEUR

=
_F
(GROUP_NO
=
(BC, BG, FG, CF))

…)

One can then define the grid m2:

S1
S2
S3

Handbook of Utilization
U4.2- booklet: Grid
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator DEFI_MAILLAGE


Date:
31/01/05
Author (S):
J. Key PELLET
:
U4.23.01-G Page
: 10/10

m2 =
DEFI_MAILLAGE
(

DEFI_MAILLE = (_F (MACR_ELEM_STAT = S1),
_F
(MACR_ELEM_STAT = S2
, MAILLE = S2,),
_F
(MACR_ELEM_STAT = S2
, MESH = S3, TRAN = 3.),),

RECO_MAILLE= (_F (MAILLE= (S1, S2), GROUP_NO= (BC, BC), OPTION=' NOEUD_A_NOEUD'),
_F
(MAILLE=
(S2, S3), GROUP_NO=
(FG, BC), OPTION=
“INVERSE”),),

DEFI_NOEUD=_F
(ALL = “YES”, INDEX = (1, 2, 2, 3))



_F (NOEUD_FIN = A, MESH = S1,
NOEUD_INIT = N1),),

DEFI_GROUP_NO =_F (GROUP_NO_FIN = FG, MESH = S3, GROUP_NO_INIT = FG),)

The grid obtained contains:

·
3 super-meshs: S1, S2, S3
·
26 nodes: With, S12,…, S317
·
1 GROUP_NO: FG = (S315, S316, S317)

S16
S15
S217
S317
S1
S2
S3
S316
With
S315
S12
S213
S313


Note:

The sticking together of the super-meshs could have been made more simply by:
RECO_GLOBAL = _F (ALL = “YES”).

Handbook of Utilization
U4.2- booklet: Grid
HT-66/05/004/A

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