Code_Aster ®
Version
7.4
Titrate:
Operator MACR_ELEM_STAT


Date:
31/01/05
Author (S):
J. Key PELLET
:
U4.62.01-G Page
: 1/8
Organization (S): EDF-R & D/AMA

Handbook of Utilization
U4.6- booklet: Elementary matrices/Vecteurs and assembly
Document: U4.62.01

Operator MACR_ELEM_STAT

1 Goal

To create macronutrients for calculations of static under-structuring.

Product a structure of data of the macr_elem_stat type.
Handbook of Utilization
U4.6- booklet: Elementary matrices/Vecteurs and assembly
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator MACR_ELEM_STAT


Date:
31/01/05
Author (S):
J. Key PELLET
:
U4.62.01-G Page
: 2/8

2 Syntax
S1 (macr_elem_stat)
= MACR_ELEM_STAT (


reuse = S1,



DEFINITION = _F (




MODELE
=
Mo
,
[model]



CHAM_MATER
=
chmat
,
[cham_mater]



CARA_ELEM
=
carac
,
[cara_elem]



CHAR_MACR_ELEM

= lchar
,
[l_char_meca]



INST

=
/inst,
[R]










/0.0
,
[DEFAUT]



NMAX_CAS
=/10,
[DEFAUT]










/nbcamx
,
[I]



NMAX_CHAR
=/10,
[DEFAUT]










/nbchmx
,
[I]








)


EXTERIEUR = _F (



| NOEUD
= l_no,
[l_noeud]



| GROUP_NO
= l_gno
,
[l_gr_noeud]







),


RIGI_MECA = _F (),


MASS_MECA = _F (),


CAS_CHARGE
=
(_F (




NOM_CAS
=
nocas
,
[k8]



SUIV =

/“OUI”
,
[DEFAUT]








/“NON”



CHARGE
=
lchar
,
[l_char_meca]



INST =/tps
,





[R]








/0.0
,
[DEFAUT]
),),












)

Handbook of Utilization
U4.6- booklet: Elementary matrices/Vecteurs and assembly
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator MACR_ELEM_STAT


Date:
31/01/05
Author (S):
J. Key PELLET
:
U4.62.01-G Page
: 3/8

3 General information

This operator is an obligatory point of passage for the static under-structuring. He is useful:

·
to define a macronutrient (key words: DEFINITION and EXTERIEUR),
·
to ask the condensation of the matrix of rigidity (or of mass),
·
to define (and condense) the associated loadings; the user can name on this occasion
one or more loading case.

These 3 stages can be made in only one call to MACR_ELEM_STAT. But they can be
make in several times thanks to the use of the key word “reuse” (enrichment of the macr_elem_stat).
The stage of definition is obligatorily to realize in first. The condensation of the mass must
to make after the condensation of rigidity.

The macr_elem_stat is a structure of data which contains:

·
its references: model, cara_elem, cham_mater, load,
·
its topological description: external nodes,
·
its condensed matrices (rigidity, mass,…),
·
a list of named condensed loadings.

The use of the whole of the operators of static under-structuring is described in a note of
U2 booklet.

4 Operands
4.1 Word
key
DEFINITION

DEFINITION

This key word factor (not répétable) is used to define the macronutrient.

4.1.1 Operand
MODELE


MODELE = Mo

Name of the model which one wants to condense. The matrices (and loadings) which one condenses
are always calculated on the model as a whole. When one wants to condense
several subsets of the same grid, it is thus necessary to create several models on
different groups of meshs.

4.1.2 Operand
CHAM_MATER


CHAM_MATER = chmat

Name of the material field associated with the model. This argument is useless if the model
contains that discrete elements and static substructures.

4.1.3 Operand
CARA_ELEM


CARA_ELEM = carac

Name of the elementary characteristics if the model comprises elements of beam, of
plate or of hull.
Handbook of Utilization
U4.6- booklet: Elementary matrices/Vecteurs and assembly
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator MACR_ELEM_STAT


Date:
31/01/05
Author (S):
J. Key PELLET
:
U4.62.01-G Page
: 4/8

4.1.4 Operands
CHAR_MACR_ELEM/INST


CHAR_MACR_ELEM = lchar

This argument is used to define:

·
the thermal loading which modifies possibly the characteristics of
material, when those depend on the temperature; one will specify if necessary
the moment of the thermal evolution (key word INST),
·
the conditions kinematics applied to the nodes intern (cf key word
EXTERIEUR) of the macro element.


INST = inst

During a calculation for which the material characteristics depend on the temperature, one
specify the field of temperature here to be used. The field used is that corresponding to
the moment inst of the thermal evolution referred in the list of the loads lchar (
to defer to command CALC_MATR_ELEM (“RIGI_MECA”)) [U4.61.01].

Remarks on the conditions kinematics:

Under the operators of static under-structuring, the conditions kinematics of
type “Dirichlet” are always dualisées, ever eliminated.

In general one will apply the conditions kinematics to the external nodes to
higher level of under-structuring. Thus they will not appear in the loads
of lchar.

On the other hand, the conditions kinematics which it is necessary to give before condensation
(lchar) are those which one will not be able to give any more afterwards:

·
the conditions implying of the nodes intern (ddl imposed or relations
linear) because these nodes will be eliminated,
·
conditions defined starting from the edges of the finite elements (FACE_IMPO) bus
these finite elements will not exist any more after condensation.

Notice on the argument lchar:

The loads which appear in the list lchar, which is those allow
to calculate the matrices of rigidity and mass:

·
possible load of temperature modifying the material characteristics,
·
conditions kinematics (dualisation).
on the other hand, these loads intervene of nothing in the definition loadings
(second members).

For example, dilations due to the field of temperature will not be taken in
count in a loading case which if the load containing this field of temperature
is explicitly given in the definition of this loading case (key words
CAS_CHARGE and CHARGE). In the same way the conditions kinematics not
null must be given again in the definition of the loading cases.

4.1.5 Operands
NMAX_CAS/NMAX_CHAR


NMAX_CAS = nbcamx

One gives one here raising of the number of loading cases which the user will define on
macronutrient (cf argument CAS_CHARGE). This number is taken by defect with 10.


NMAX_CHAR = nbchmx

One gives one here raising of the number of concepts of the type charges that one will affect to
each loading case (cf argument CAS_CHARGE). This number is taken by defect with 10.
Handbook of Utilization
U4.6- booklet: Elementary matrices/Vecteurs and assembly
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator MACR_ELEM_STAT


Date:
31/01/05
Author (S):
J. Key PELLET
:
U4.62.01-G Page
: 5/8

4.2 Word
key
EXTERIEUR

EXTERIEUR
=

This key word factor (not répétable) is used to define the whole of the “external” nodes where will be
digests matrices and loadings (the other nodes will be known as “internal”). This key word
in the first call to command MACR_ELEM_STAT (one must appear defines outside
of a macronutrient in only once).

Each external node carries the same degrees of freedom as the node corresponding of the model
Mo. A macronutrient (and geometrically) entirely is topologically defined by
the whole of its external nodes.

4.2.1 Remarks on the definition of the “outside” of a macro element

·
The outside of a macronutrient is the whole of the “external” nodes which define
topology and geometry of the macronutrient,
·
each “external” node carries all the degrees of freedom which exist on this node in
subjacent model. The macronutrients produced by Aster are usable only in
resticking their external nodes and consequently all degrees of freedom which it carry.
Other computer codes operate differently. For certain modelings (slip,
articulation,…), one will be led not to restick certain nodes and to use, on the level of
under-structuring superior, of the linear relations between the degrees of freedom of the nodes
external several macronutrients,
·
at the time of the definition of the external nodes of a macronutrient, if a node appears several
time, one counts it only only once,
·
for reasons of programming, it is necessary that there are at the same time external nodes and
internal nodes: none the families can be empty.

4.2.2 Operands
NODE/GROUP_NO


|
NOEUD = l_noeu

List names of nodes which one wishes “external”.


|
GROUP_NO = l_grno

List names of the groups of nodes which one wishes “external”.

4.3 Words
keys
RIGI_MECA/MASS_MECA

RIGI_MECA

This key word is used to specify that one wants to condense the matrix of rigidity. This matrix is
calculated on all the elements of the model like on the elements of LAGRANGE of
conditions kinematics contained in the argument of CHAR_MACR_ELEM.

MASS_MECA

This key word is used to specify that one wants to condense the matrix of mass. This matrix is
calculated on all the elements of the model (condensation of GUYAN).
Handbook of Utilization
U4.6- booklet: Elementary matrices/Vecteurs and assembly
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator MACR_ELEM_STAT


Date:
31/01/05
Author (S):
J. Key PELLET
:
U4.62.01-G Page
: 6/8

4.4 Word
key
CAS_CHARGE


CAS_CHARGE

This key word factor makes it possible to define a whole of named loading cases (key word NOM_CAS).
These loading cases could be applied to the model of higher level (CALC_VECT_ELEM
[U4.61.02]).

In general, one will seek to apply the nodal loadings (FORCE_NODALE) to the level
superior of under-structuring.

On the other hand all the loadings defined on the finite elements must be applied above all
condensation: (GRAVITY, ROTATION, FORCE_FACE, FORCE_CONTOUR, FORCE_INTERN,
FORCE_COQUE, FORCE_POUTRE, PRES_REP,…) since these finite elements “will have disappeared”
after condensation.

Let us note that for a macronutrient, there is no concept of contour, orientation, of face,…

4.4.1 Operand
NOM_CAS



NOM_CAS = nocas

The loading condensed under the name nocas (between “quotes”) corresponds to
loading defined by the arguments of CHARGE and INST to which one adds
systematically loadings of name nocas possibly present on
under structures of lower level contained in the model Mo.

4.4.2 Operand
SUIV



SUIV = “YES”/“NOT”

This key word said if the loading case “follows” the macronutrient in its transformations
geometrical: translation, rotation, (cf operator DEFI_MAILLAGE [U4.23.01]). By
example, the loading due to a rotation (centrifugal force), a pressure (or one
opposed dilation) is “following” because its direction is related to the position of
substructure. On the other hand, gravity is a loading “not follower” (his direction
is absolute).

Caution:

The loadings kinematics are always “following” because their catch in
account is made in the matrix of rigidity (dualisation) and this matrix is
“following” by nature.

4.4.3 Operands
CHARGE/INST



CHARGE = lchar,


INST = tps,

Key words CHARGE and INST have the same significance as in the operator
CALC_VECT_ELEM [U4.61.02].
Handbook of Utilization
U4.6- booklet: Elementary matrices/Vecteurs and assembly
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator MACR_ELEM_STAT


Date:
31/01/05
Author (S):
J. Key PELLET
:
U4.62.01-G Page
: 7/8

5
Examples of definition of a macro element

5.1
To define the outside of a macronutrient

sup1 =
MACR_ELEM_STAT
(

DEFINITION
=
_F
(
MODELE
=
Mo,
CHAM_MATER
=
chmat),



OUTSIDE = _F (GROUP_NO = EXT.),








)

sup3 =
MACR_ELEM_STAT
(



DEFINITION = _F (MODELE = Mo,
CHAM_MATER
=
chmat,),



OUTSIDE = _F (NODE = (“N3”, “N4”), GROUP_NO = (“L1”, “L3”),)

5.2
To condense matrices of rigidity and mass

sup1 =
MACR_ELEM_STAT
(reuse = sup1,



RIGI_MECA = _F (), MASSE_MECA = _F (),








)

5.3
To define a loading on the macronutrient

sup1 =
MACR_ELEM_STAT
(reuse = sup1,



CAS_CHARGE = (NOM_CAS = “CH1”, LOAD = CH1,),








)

5.4 To define the macronutrient, its loadings, and to ask
condensation of the matrices

sup2 =
MACR_ELEM_STAT
(



DEFINITION
= _F
(MODELE = Mo, CHAM_MATER = chmat),
EXTERIEUR
=
_F (
GROUP_NO
=
EXT
),
RIGI_MECA
=
_F (),
MASSE_MECA = _F (),



CAS_CHARGE
= _F
(NOM_CAS = “CH1”, LOAD = CH1),









)

Handbook of Utilization
U4.6- booklet: Elementary matrices/Vecteurs and assembly
HT-66/05/004/A

Code_Aster ®
Version
7.4
Titrate:
Operator MACR_ELEM_STAT


Date:
31/01/05
Author (S):
J. Key PELLET
:
U4.62.01-G Page
: 8/8

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Handbook of Utilization
U4.6- booklet: Elementary matrices/Vecteurs and assembly
HT-66/05/004/A

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