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:
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Organization (S): EDF-R & D/AMA
Handbook of Utilization
U4.4- booklet: Modeling
Document: U4.42.01
Operator AFFE_CARA_ELEM
1 Goal
To assign to elements of structure of the geometrical and material characteristics. Data
geometrical affected are complementary to the data of grid.
Among the treated characteristics let us quote:
· for the elements of the hull type: the thickness, a direction of reference in the tangent plan,
· for the elements of the beam type: characteristics of the cross section and
orientation of the principal axes of inertia around neutral fiber, curvature of the elements
curves,
· for the elements of the discrete type (arises, mass/inertia, damping device): values of
matrices of rigidity, mass or damping to be affected directly or after orientation,
· for the elements of the type bars or of type cables: the surface of the cross section,
· for the elements of mediums continuous 3D and 2D: local axes by report/ratio to which
the user will be able to define directions of anisotropy.
The command must be exhaustive for all the elements of structure of the model.
This operator produces a structure of the cara_elem type.
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2 Syntax
general
will cara [cara_elem] = AFFE_CARA_ELEM (
MODELE
=
Mo
,
[model]
INFO =/1,
[DEFAUT]
/2,
VERIF = | “MAILLE”,
| “NOEUD”,
| BARRE
=
(see key word BARRE
[§6])
| CABLE
=
(see key word CABLE
[§7])
| COQUE
=
(see key word COQUE
[§8])
| POUTRE
=
(see key word POUTRE
[§9])
ORIENTATION
=
(see key word ORIENTATION [§10])
DEFI_ARC
=
(see key word DEFI_ARC [§11])
| AFFE_SECT
=
(see key word AFFE_SECT
[§12])
| AFFE_FIBER = (see key word AFFE_FIBER [§12])
| DISCRET =
(see key word DISCRET [§13])
ORIENTATION
=
(see key word ORIENTATION [§10])
| DISCRET_2D =
(see key word DISCRET_2D
[§13])
ORIENTATION
=
(see key word ORIENTATION [§10])
| MASSIF
=
(see key word MASSIF
[§14])
| ASSE_GRIL
=
(see key word ASSE_GRIL
[§15])
| POUTRE_FLUI
=
(see key word POUTRE_FLUI [§16])
| GRILL
=
(see key word GRILL
[§17])
| RIGI_PARASOL
=
(see key word RIGI_PARASOL [§18])
| RIGI_MISS_3D
=
(see key word RIGI_MISS_3D [§19])
)
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3 Operands
Generals
MODELE and VERIF
3.1 Operand
MODELE
MODELE = Mo
Concept of the model type, produced by the operator AFFE_MODELE [U4.41.01] on whom are
affected characteristics of the elements. Let us note that the model must contain explicitly with
less one of the elements of structure, on which will carry the assignment (if not calculation stops).
3.2 Operand
VERIF
VERIF
=/“MAILLE”
/
“NOEUD”
Argument Significance
Check that the type of element supported by the meshs, to which one
wants to affect a characteristic, is compatible with this
“MAILLE”
characteristic (including the orientations).
In the contrary case, stop with error message.
Check that the nodes to which one wants to affect a characteristic
“NOEUD”
nodal support a type of element compatible with this
(only with
characteristic. In the contrary case, stop with error message.
DISCRET)
3.3 Operand
INFO
INFO
=
/2
Print on file “MESSAGE”, for all the elements, the list of
values assigned to the elements:
- angles of orientation in degrees (beams and discrete),
- characteristics of the cross sections of beams and of
bars,
- impressions of the elementary matrices (discrete).
/
1
do not print anything
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4
Definition of the field of assignment
The choice of the elements of the model Mo to which the assignment relates makes in two stages:
1) the choice of the type of element concerned with assignment (POUTRE, DISCRET,…),
2) meshs (of the type of definite element) to affect.
The choice of the key word factor defining the type of elements (POUTRE, DISCRET,…) imply that it
exist in the model the types of adapted elements (checking carried out systematically).
The types of elements concerned depend on modeling:
· phenomenon MECANIQUE
Key word
Modeling
BAR BARS
CABLE CABLE,
CABLE_POULIE
COQUE
HULL AXIS, HULL C PLANE, HULL D PLANE, DKT, DST,
DKQ, DSQ, Q4G, COQUE_3D
DISCRET
DIS_T, DIS_TR, 2D_DIS_T, 2D_DIS_TR
POUTRE
LOUSE D E, LOUSE D T, LOUSE C T, LOUSE D TG, LOUSE D T GD,
FLUI_STRU, TUYAU_3M, TUYAU_6M, POU_D_TGM, POU_D_EM
MASSIF
3D, AXIS, FOURIER AXIS, C PLANE, D PLANE, PIPE 3M,
TUYAU_6M
ROAST GRID,
GRILL_MEMBRANE
ASSE_GRIL ASSE_GRIL
POUTRE_FLUI 3d_FAISCEAU
AFFE_SECT POU_D_EM,
POU_D_TGM
AFFE_FIBER POU_D_EM,
POU_D_TGM
RIGI_PARASOL DIS_TR
RIGI_MISS_3D DIS_T
· phenomenon THERMIQUE
Key word
Modeling
COQUE
COQUE_AXIS, COQUE_PLAN, HULL
MASSIF
3D, AXIS, PLAN
The assignment of the characteristics to the finite elements is done using the key words: “MAILLE”,
“NOEUD”, “GROUP_MA”, “GROUP_NO”, according to the cases.
· If VERIF is not present: In a group or a list of meshs (or nodes), one affects
indeed characteristics with the only elements for which they have a direction. For
other elements, the characteristics are not affected.
· If VERIF is present: One checks moreover than all the elements of the group or of the list are
good type, if not an error message is transmitted.
4.1 Operands
NET/GROUP_MA/NODE/GROUP_NO
Operands Significance
GROUP_MA = lgma
Assignment with all the elements of the groups of meshs specified.
MAILLE = lma
Assignment with all the elements of the specified meshs.
GROUP_NO = lgno
Assignment with all the nodes of the groups of specified nodes (DISCRET
only)
NOEUD = lno
Assignment with all the specified nodes (DISCRET only)
As in the other commands, the rule of overload applies [U1.03.00].
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5
Assignment of values
Two methods are usable to affect values of characteristics:
· traditional method: operand whose name evokes the treated characteristic followed by a value
or of a list of values. Examples:
HULL = _F (THICK = 1.E-2,
GROUP_MA = “G1”),
HULL = _F (ANGL_REP = (0., 90.), GROUP_MA = “G2”),
· for the assignments relating to BARRE, POUTRE and DISCRET, like ORIENTATION for
elements of beam and discrete elements, the great number of characteristics which can be
affected led to a better adapted syntax:
CARA = (...) # lists names of characteristics
VALE = (...) # lists values corresponding to the characteristics
One gives an illustrative example below this case.
0,4
0,05
0,02
0,02
0,01
M1
M2
M3
M4
M5
M6
0,2
0,018
N1
N2
N3
N4
N5
N6
N7
Description of the meshs:
SEG2
M1
N1
N2
M2
N2
N3
M3
N3
N4
M4
N5
N4
M5
N5
N6
M6
N6
N7
FINSF
Command file:
= AFFE_CARA_ELEM will cara (
POUTRE=
(_F (SECTION=' CERCLE', CARA= (“R”, “EP”), VALE= (0.1, 0.02), MAILLE= (“M1”, “M5”)),
_F (SECTION=' CERCLE', CARA= (“R”, “EP”), VALE= (0.2, 0.05), MAILLE= “M3”),
_F (SECTION=' CERCLE', CARA= (“R”, “EP”), VALE= (0.09, 0.01), MAILLE= “M6”),
_F (SECTION=' CERCLE', CARA= (“R1”, “R2”), VALE= (0.1, 0.2), MAILLE= (“M2”, “M4”)),
_F (SECTION=' CERCLE', CARA= (“EP1”, “EP2”), VALE= (0.02, 0.05), MAILLE= (“M2”, “M4”)),
),
)
It is also possible to use the functionalities of the language python. The example below
recover sizes calculated by command MACR_CARA_POUTRE, for then affecting them.
The use of python requires to put PAR_LOT=' NON' in command DEBUT.
PRE_GIBI ()
SECTION = MACR_CARA_POUTRE (NOEUD= “N1”, GROUP_MA_BORD= “EDGE”)
II = 2
alpha0 = SECTION [“ALPHA”, II]
cdgx0 = SECTION [“CDG_X”, II]
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cdgy0 = SECTION [“CDG_Y”, II]
AIRE0 = SECTION [“AIRE”, II]
IY0 = SECTION [“IY_PRIN_G”, II]
IZ0 = SECTION [“IZ_PRIN_G”, II]
EY0 = SECTION [“EY”, II]
EZ0 = SECTION [“EZ”, II]
JX0 = SECTION [“CT”, II]
JG0 = SECTION [“JG”, II]
AY0 = SECTION [“AY”, II]
AZ0 = SECTION [“AZ”, II]
IYR20 = SECTION [“IYR2_PRIN_G”, II]
IZR20 = SECTION [“IZR2_PRIN_G”, II]
carelem=AFFE_CARA_ELEM (MODELE=mod,
POUTRE = (
_F (GROUP_MA= (“POUT1”, “POUT2”), SECTION=' GENERALE',
CARA= (“A”, “IY”, “IZ”, “AY”, “AZ”, “EY”, “EZ”, “JX”, “JG”, “IYR2”, “IZR2”),
VALE= (AIRE0, IY0, IZ0, AY0, AZ0, EY0, EZ0, JX0, JG0, IYR20,
IZR20),),
)
)
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6 Word
key
BARRE
6.1 Characteristics
allocatable
Allows to affect the characteristics of the cross sections of elements of the type BARRE. One can
to treat three types of cross sections defined by operand SECTION.
With each type of section, it is possible to affect various characteristics identified by one or
several names (operand CARA) to which as many values (operand VALE) are associated.
6.2 Syntax
BARRE= (
_F (
/
MAILLE
=
lma, [l_maille]
/
GROUP_MA
=
lgma,
[l_gr_maille]
/SECTION = “GENERAL”,
# constant section
CARA =
“A”,
VALE
=
goes
,
[l_R]
/
SECTION = “RIGHT-ANGLED”,
# constant section
CARA=/(| “H” | “EP”),
/(| “HY” | “HZ” | “EPY” | “EPZ”),
VALE
=
goes,
[l_R]
/
SECTION = “CIRCLE”,
# constant section
CARA=
(| “R” | “EP”),
VALE= goes,
[l_R]
FCX
=
fv,
[FONCTION]
),
)
Regulate use:
one cannot overload a type of section (CERCLE, RECTANGLE, GENERALE) by another.
6.3 Operands
6.3.1 Operand
SECTION = “GENERAL”
The only characteristic required in this case is the surface of the cross section of bar “A”.
6.3.2 Operand
SECTION = “CIRCLE”
CARA
Significance
Default value
R
Radius external of the tube
Obligatory
EP
Thickness in the case of a hollow tube
Full tube (EP=R)
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Y
G
Z
R
EP
These values are used to calculate surface “A” of the section.
6.3.3 Operand
SECTION = “RIGHT-ANGLED”
CARA
Significance
Default value
/HY
Dimension of the rectangle following GY Obligatoire
HZ
Dimension of the rectangle following GZ Obligatoire
/H
Length of the edge (if the rectangle is square)
Obligatory
/EPY
Thickness according to GY in the case of a hollow tube
HY/2
EPZ
Thickness according to GZ in the case of a hollow tube
HZ/2
/EP
Thickness along the two axes in the case of a hollow tube
Full tube
Y
EPY
HY
G
Z
EPZ
HZ
Rules of use: for a given mesh
· “H” is incompatible with “HZ” and “HY”
· “EP” is incompatible with “EPY” and “EPZ”.
6.4 Operand
`FCX `
FCX
=
fv
Assignment of a function describing the dependence of the force distributed with respect to the speed of
wind relative (see for example [V6.02.118]).
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7 Word
key
CABLE
7.1 Characteristics
allocatable
Allows to assign a constant section to the elements of the type cables or cable-pulley.
7.2 Syntax
CABLE = (
_F (
/
MAILLE
=
lma,
[l_maille]
/
GROUP_MA
=
lgma,
[l_gr_maille]
SECTION
=
surface,
[R]
FCX
=
fv,
[FONCTION]
N_INIT
=/No,
[R]
/
5000,
[DEFAUT]
),
)
7.3 Operand
`SECTION `
SECTION: surface
Allows to define the surface of the cross section of the cable.
7.4 Operand
`FCX `
FCX
:
fv
Assignment of a function describing the dependence of the force distributed with respect to the speed of
wind relative (HM-77/01/046) to see for example test SDNL102 [V5.02.102].
7.5 Operand
N_INIT
Defines the initial tension in the cable, 5000 NR by defect for cables whose dimensions are
defined in meters.
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8 Word
key
COQUE
8.1 Characteristics
allocatable
The characteristics which one can affect on the elements of plate or hull are:
· for all the elements of this type, a constant thickness on each mesh, since it
grid represents only the average layer (or of diagram for offset),
· for certain models of hull, particular characteristics: coefficient of shearing,
metric, offsetting,…
· for the analysis of the generalized efforts, state of stress or deformations, one
direction of reference for groups of meshs.
8.2 Syntax
COQUE= (
_F (
/
MAILLE
=
lma,
[l_maille]
/
GROUP_MA
=
lgma,
[l_gr_maille]
EPAIS
=
ep,
[R]
ANGL_REP
=
/
(0.,
0.),
[DEFAUT]
/(,
),
[l_R]
MODI_METRIQUE
=/“NON”,
[DEFAUT]
/“OUI”,
COEF_RIGI_DRZ
=/KRZ
,
[R]
/
1.E-5,
[DEFAUT]
EXCENTREMENT
=
E,
[R]
0., [DEFAUT]
INER_ROTA
= “OUI”,
COQUE_NCOU =/
n1,
[I]
/1,
[DEFAUT]
),
)
8.3 Operands
8.3.1 Operand
EPAIS
EPAIS = ep
Note:
The thickness must be expressed with the same units as the co-ordinates of the nodes of
grid.
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8.3.2 Operands MODI_METRIQUE/COEF_RIGI_DRZ/OFFSETTING/INER_ROTA
/MODI_METRIQUE
=
“NON”,
Fact the assumption that the thickness of the element is low. There is no integration in
the thickness but only according to the surface of the average layer (default option for all
hulls).
/MODI_METRIQUE
=
“OUI”,
For modelings of thick hulls
: COQUE_AXIS, COQUE_C_PLAN,
COQUE_D_PLAN, COQUE_3D, integrations are done by taking of account the variations in
function thickness.
EXCENTREMENT
=/E,
/0.
The distance between surface with a grid and average surface defines, in the direction of the normal
(modelings DKT, DST, GRILL).
INER_ROTA
= “OUI”
Taking into account of the inertia of rotation for modeling DKT, DST and Q4G. It is obligatory
in the event of offsetting. One can omit this key word for thin hulls, where terms
of inertia of rotation are negligible compared to different in the matrix of mass [R3.07.03].
COEF_RIGI_DRZ = KRZ,
KRZ is a coefficient of fictitious rigidity (necessarily small) on the degree of freedom of rotation
around the normal with the hull. It is necessary to prevent that the matrix of rigidity is
singular, but must be selected smallest possible. The default value (1.E-5) is appropriate for
majority of the situations (it is a relative value: rigidity around the normal is equal to KRZ
time the diagonal minor term of the matrix of rigidity of the element).
Note:
Attention, in STAT/DYNA_NON_LINE, this coefficient can involve iterations of
Newton additional (more than one iteration for a linear problem for example).
8.3.3 Operand
ANGL_REP
ANGL_REP = (,),
This key word is used for the definition of a local reference mark in the tangent plan in any point of a hull.
The construction of the local reference mark is done using the two “nautical” angles and (provided in
degrees) which define a vector v whose projection on the tangent level with the hull fixes
direction xl.
The vector V is defined in the total reference mark (O, X, Y, Z) by two rotations and:
Y
Z
Y1
X
1
V
O
X
O
X1
Appear 8.3.3-a
Appear 8.3.3-b
Rotation around OZ transforms (OXYZ) into
Rotation - around OY1 OX1 transforms into V
(OX1 Y1 Z)
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In three-dimensional representation [Figure 8.3.3-c].
Z
V
Y1
Y
X
Appear 8.3.3-c
One can define a single vector V for all the structure, or one by zone (key words GROUP_MA
/MAILLE).
The construction of the local reference mark in a point of an element of hull is carried out starting from V, of
following way:
· the projection of V on the tangent level provides the axis xl,
· the normal in tangent plan N is known for each element.
The local reference mark is thus: (P, xl, yl, zl) with: xl = XR, zl = N and yl supplements the trihedron.
zl = N
V
yl
P
xl
tangent plan
Important remark:
The definition of this reference axis is useful:
· on the level it postprocessing, to define the local trihedron in which the efforts are expressed
generalized or constraints. The user will have to take care that the selected reference axis
does not find itself parallel with the normal of certain meshs of the grid: (Example: In
case or ANGL_REP = (0., 0.) by defect for a parallel plate in plan (Y, Z) of the reference mark
GLOBAL an error message is emitted during the calculation of option “EFGE_ELNO_DEPL” of
CALC_ELEM [U4.81.01]). The possibility of defining a posteriori a group of meshs of which
normal is in a given solid angle is possible by command DEFI_GROUP
[U4.22.01],
· to lay down the orientation of fibers of a multi-layer hull (Cf. operator DEFI_COQU_MULT
[U4.42.03]).
8.3.4 Operand
COQUE_NCOU
A number of layers used for integration in the thickness of the hull, the operators
STAT_NON_LINE and DYNA_NON_LINE (modelings DKT,
COQUE_3D,
COQUE_AXIS,
COQUE_C_PLAN, COQUE_D_PLAN).
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9 Word
key
POUTRE
9.1 Characteristics
allocatable
This key word makes it possible to affect the characteristics of the cross sections of elements of the beam type
(modelings POU_D_E, POU_D_EM, POU_D_T, POU_C_T, POU_D_TG, POU_D_TGM, POU_D_T_GD,
TUYAU_3M, TUYAU_6M). One can treat three types of cross sections defined by the operand
SECTION.
With each type of section, it is possible to affect various characteristics identified by one or
several names (operand CARA) to which as many values (operand VALE) are associated.
It is possible to treat beams of constant section (name of characteristic without suffix) or of
variable section (name of characteristic with suffix 1 or 2). The mode of variation of the section is
defined by key word VARI_SECT (cf [§9.4.1]). One then gives the characteristics of the section to
initial node (name with suffix 1) and with the final node (name with suffix 2) (“initial” and “final” relative with
the classification of the mesh support). One must also use this key word to define the constant of
torsion for modeling (POU_D_EM).
9.2 Syntax
POUTRE= (
_F (
/
MAILLE
= lma,
[l_maille]
/
GROUP_MA
=
lgma,
[l_gr_maille]
/SECTION = “GENERAL”,
VARI_SECT
=
“CONSTANT” [DEFECT]
“HOMOTHETIQUE”
# constant section
/CARA =
| “A” | “IY” | “IZ”,
| “AY” | “AZ” | “EY” | “EZ”,
| “JX” | “AI” | “RY” | “RZ” | “RT”,
| “JG” |' IYR2' |' IZR2' |,
VALE
=
goes,
[l_R]
# section homothetic
/
CARA = | “A1” | “A2” | “IY1” | “IY2”,
| “IZ1” | “IZ2” | “JX1” | “JX2”,
| “AY1” | “AY2” | “AZ1” | “AZ2”,
| “JG1” | “JG2” | “EY1” | “EY2”,
| “EZ1” | “EZ2” | “AI1” | “AI2”,
| “RY1” | “RY2” | “RZ1” | “RZ2”,
| “RT1” | “RT2”,
| “IYR21” | 'IZR21'| “IYR22” | “IZR22”,
VALE = goes,
[l_R]
/
SECTION = “RIGHT-ANGLED”,
VARI_SECT
=
/
“CONSTANT”,
[DEFAUT]
/
“HOMOTHETIQUE”,
/“AFFINE”,
# constant section
/
CARA =/ | “H” | “EP”,
/ | “HY” | “HZ” | “EPY” | “EPZ”,
VALE = goes,
[l_R]
# section homothetic
/
CARA =/ | “H1” | “H2” | “EP1” | “EP2”,
/ | “HY1” | “HZ1” | “HY2” | “HZ2”,
| “EPY1” | “EPY2” | “EPZ1” | “EPZ2”,
VALE = goes,
[l_R]
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# section closely connected
/
CARA = | “HY” | “EPY” | “HZ1”,
| “EPZ1” | “HZ2” | “EPZ2”,
VALE = goes,
[l_R]
/
SECTION = “CIRCLE”,
VARI_SECT
=
“CONSTANT” [DEFECT]
“HOMOTHETIQUE”,
# constant section
/CARA=
| “R” | “EP”,
VALE
=
goes,
[l_R]
# section homothetic
/CARA
= | “R1” | “R2” | “EP1” | “EP2”,
VALE = goes,
[l_R]
MODI_METRIQUE
=/“OUI”,
/
“NON”,
[DEFAUT]
TUYAU_NSEC =/nsec,
[I]
/16,
[DEFAUT]
TUYAU_NCOU =/ncou,
[I]
/
3,
[DEFAUT]
FCX
=
fv,
[FONCTION]
PREC_AIRE
=
/
precis, [R]
/
0.01,
[DEFAUT]
PREC_INERTIE
=
/
precis, [R]
/
0.1, [DEFAUT]
),
)
9.3 Rules
of use
Note:
The orientation of the elements of beams is done by key word ORIENTATION [§10]. The angle of gimlet
(which makes it possible to direct the transverse section of the beam around its neutral fiber) is always
given to direct the principal axes of the section what is not very practical because these axes are in
General unknown before the calculation of the geometrical characteristics of the section
(cf MACR_CARA_POUTRE [U4.42.02]).
· It is possible starting from version 6 to directly provide (via variables python) them
characteristics of the sections (general) resulting from a calculation with MACR_CARA_POUTRE. This
is implemented in test SSLL107F.
· The various names of characteristics arguments of operand CARA are described further for
each argument of operand SECTION.
· For a given mesh:
- One cannot overload a type of variation of section (constant or variable) by another.
- One cannot overload a type of section (CERCLE, RECTANGLE, GENERALE) by another.
- For the beams non-prismatic, the names with suffix 1 or 2 are incompatible with
names without suffix. Example: A is incompatible with A1 and A2.
- “H” is incompatible with “HZ” and “HY” (like H1, H2,…)
- “EP” is incompatible with “EPY” and “EPZ” (like EP1, EP2,…).
- “RY”, “RZ” and “RT” intervene only for the calculation of the constraints.
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9.4 Operands
9.4.1 Operand
VARI_SECT
Allows to define the type of variation of section between the two nodes ends of the element of
beam (elements POU_D_E and POU_D_T [R3.08.01]).
The possibilities are:
Section Closely connected Homothetic
ring not yes
rectangle
yes (according to Z)
yes
general not
yes
· “Closely connected” means that the surface of the section varies in a linear way between the two nodes.
dimensions in the direction are there constant (HY, EPY) and that in direction Z vary
linearly (HZ1, HZ2, EPZ1, EPZ2).
· “Homothetic” means that 2 dimensions of the section vary linearly between
values given to the two nodes, the surface of the section thus evolves/moves in a quadratic way.
9.4.2 Operand
MODI_METRIQUE
Allows to define for elements TUYAU the type of integration in the thickness (modelings
TUYAU_3M, TUYAU_6M):
· MODI_METRIQUE = “NON” results in assimilating in integrations the radius to the average radius.
This is thus valid for the pipes low thickness (relative with the radius),
· MODI_METRIQUE = “OUI” implies a complete integration, more precise for pipings
thick, but being able in certain cases to lead to oscillations of the solution.
9.4.3 Operand
SECTION = “GENERAL”
9.4.3.1 Section
constant
CARA
Significance
Default value
With
Surface of the section
Obligatory
IZ
Geometrical moment of inertia principal compared to GZ Obligatoire
IY
Geometrical moment of inertia principal compared to GY Obligatoire
Obligatory if POU_D_T,
AY
Coefficient of shearing in direction GY
POU_C_T, POU_D_TG
0. if POU_D_E
AZ
Coefficient of shearing in direction GZ
idem
EY
Eccentricity of the center of torsion
0.
(component of CG following GY)
EZ
Eccentricity of the center of torsion
0.
(component of CG following GZ)
JX
Constant of torsion
Obligatory
RY
Distance from an external fiber measured according to y
1.
RZ
Distance from an external fiber measured according to Z
1.
RT
Effective radius of torsion
1.
JG
Constant of warping (POU_D_TG, POU_D_TGM)
IYR2
Necessary to the calculation of geometrical rigidity
(POU_D_TG and POU_D_TGM)
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IZR2
Necessary to the calculation of geometrical rigidity
(POU_D_TG and POU_D_TGM)
AI
Surface of the bypass section of the fluid inside the obligatory one for one
beam.
modeling FLUI_STRU
9.4.3.2 Section
homothetic
One defines the characteristics for each mesh, with the two nodes.
CARA
Significance
Default value
A1, A2
Surface of the section
Obligatory
IZ1, IZ2
Geometrical moment of inertia principal per report/ratio
Obligatory
with GZ
IY1, IY2
Geometrical moment of inertia principal per report/ratio
Obligatory
with GY
Obligatory if POU_D_T,
AY1, AY2
Coefficient of shearing in direction GY
POU_C_T, POU_D_TG
0. if POU_D_E
AZ1, AZ2
Coefficient of shearing in direction GZ
idem
EY1, EY2
Eccentricity of the center of torsion
0.
(component of CG following GY)
EZ1, EZ2
Eccentricity of the center of torsion
0.
(component of CG following GZ)
JX1, JX2
Constant of torsion
Obligatory
RY1, RY2
Distance from an external fiber measured according to y
1.
RZ1, RZ2
Distance from an external fiber measured according to Z
1.
RT1, RT2
Effective radius of torsion
1.
JG1, JG2
Constant of warping (POU_D_TG)
IYR21, IYR22
Necessary to the calculation of geometrical rigidity
(POU_D_TG and POU_D_TGM)
IZR21, IZR22
Necessary to the calculation of geometrical rigidity
(POU_D_TG and POU_D_TGM)
AI1, AI2
Surfaces of the bypass section of the fluid with
obligatory for one
interior of the beam.
modeling
FLUI_STRU
Y
Y
RT
X
by (T)
RY
neutral fiber
T
Z
G
G
EY
Z
C
EZ
RZ
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Definition of the characteristics:
IZ =
y 2ds
IY = Z 2ds
S
S
2
With
With
y m
2
2
y (y)
With
With
z2 mz (Z)
RY
AY =
=
=
=
'
2
'
2
:
with y
=
With
IZ
y1 B
Y
y (y) Dy
AZ
With
IY
z1 B
Z
Z (Z) dz
m (y)
Tb (T) dt
y
y
by (T) thickness
according to
Z, in Z = T
with:
A', A'
Y
Z: sheared reduced surfaces
With
1
A' =
front
AY
EC.
.
1 or A' = K A with K
Y
=
.
1
AY
Y
y
y
AY
· coefficients of shearing A, A
Y
Z are used by elements POU_D_T, POU_C_T and
POU_D_TG, POU_D_TGM, for the calculation of the matrices of rigidity and mass and for the calculation of
constraints [R3.08.01]. In particular, stresses shear transverse are expressed by:
Z
V
Z
With
With
=
= V
,
Y
xz
Z
xz = Y
V
,
kz A
With
With
· in the case of the beams of Euler (POU_D_E) which do not take account of transverse shearing,
one neglects the corresponding terms in the calculation of rigidity and the mass while taking
WITH = A
Y
Z = 0. On the other hand, the constraints [R3.08.01] of shearing are calculated by:
Z
V
=
,
Y
V
xz
xz =
.
With
With
Characteristics RY, RZ, RT are used for calculation of torsion and bending stresses
[R3.08.01] for options “SIGM_ELNO_DEPL” or “SIPO_ELNO_DEPL” of CALC_ELEM [U4.81.01].
My
In inflection, one a: xx =
. RZ
Iy
M
or
Z. RY
Iz MT
In torsion,
=
xz
xy =
. RT
JX
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9.4.4 Operand
SECTION = “RIGHT-ANGLED”
CARA
Significance
Default values
Constant section
HY
Dimension of the rectangle following GY
Obligatory
HZ
Dimension of the rectangle following GZ
Obligatory
H
Dimension of the square (if the rectangle is square)
Obligatory
EPY
Thickness according to GY in the case of a hollow tube
HY/2
EPZ
Thickness according to GZ in the case of a hollow tube
HZ/2
EP
Thickness along the two axes in the case of a tube
Full tube
hollow
Homothetic section
H1, H2
Dimension of the square at each end for one
H1=H2=H
variable section
HY1, HY2
Dimension of the rectangle following GY at each end
HY1=HY2=HY
for a variable section
HZ1, HZ2
Dimension of the rectangle following GZ at each end
HZ1=HZ2=HZ
for a variable section
EP1, EP2
Thickness along the two axes in the case of a tube
EP1=EP2=EP
hollow, at each end in the case of a section
variable
EPY1, EPY2
Thickness according to GY in the case of a hollow tube, with
EPY1=EPY2=EPY
each end in the case of a variable section
EPZ1, EPZ2
Thickness according to GZ in the case of a hollow tube, with
EPZ1=EPZ2=EPZ
each end in the case of a variable section
Y
EPY
Z
HY
G
EPZ
HZ
The characteristics calculated by Aster are [R3.08.03]:
HY. HZ3 (HY - 2EPY).(HZ - 2EPZ) 3
Iy =
-
12
12
HZ. HY 3 (HZ - 2EPZ).(HY - 2EPY) 3
Iz =
-
12
12
HY
HZ
RY =
RZ =
2
2
· If the tube is hollow:
AY = AZ = 15
.
2 EPY.EPZ (HY - EPY) 2 (HZ - EPZ) 2
JX =
HY.EPY + HZ.EPZ - EPY 2 - EPZ2
JX
RT = 2EPZ (HY - EPY) (HZ - EPZ)
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· If the tube is full:
HY
HZ
one poses
has =
, B =
if HY > HZ
2
2
HZ
HY
has =
, B =
if HZ > HY
2
2
6
-
coefficients of shearing AY = AZ =
5
16
B
b5
-
J = has b3
- 3 3
. 6
+ 0 2
. 8
3
has
a5
J (3a +18
. b)
-
RT =
8a2 b2
Note:
The computed values can be printed with the key word INFO = 2.
9.4.5 Operand
SECTION = “CIRCLE”
CARA
Significance
Default value
Constant section
R
Radius external of the tube
Obligatory
EP
Thickness in the case of a hollow tube
Full tube (EP=R)
Variable section
R1, R2
Radii external at the two ends for one
R1=R2=R
variable section
EP1, EP2
Thicknesses at the two ends in the case of one
EP1=EP2=EP
variable section
Y
G
Z
R
EP
The computed values by Aster are [R3.08.03]:
JX
R4
(R - EP) 4
I = I
y
Z =
=
-
2
4
4
RT = RY = RZ = R
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· full tube: AY = AZ = 10/9
· tube hollow thick:
R - EP
if
< 9
.
0
that is to say EP >
1
.
0 R
R
R - EP
that is to say =
AY = AZ = - 0 905 3 + 1156 2
.
.
+ 0 634
.
+1093
.
R
· if not (thin tube) AY = AZ = 2.
9.5 Operand
`FCX `
FCX
=
fv
Assignment of a function describing the dependence of the force distributed with respect to the speed of
wind relative (see test SSNL118 [V6.02.118]). The loading of the wind type is applicable on
elements of bar of cable and beam (modelings POU_D_E, POU_D_T, POU_D_T,
POU_D_TG, POU_D_TGD, POU_D_TGM).
9.6 Operands
TUYAU_NSEC/TUYAU_NCOU
TUYAU_NSEC =/nsec,
TUYAU_NCOU =/ncou,
A number of layers in the thickness (ncou by defect = 3) and of sectors (nsec by defect = 16)
on the circumference used for integrations in elements TUYAU [R3.08.06].
9.7 Operands
PREC_AIRE/PREC_INERTIE
PREC_AIRE
=/precise,
PREC_INERTIE
=/precise,
The use of the multifibre beams (POU_D_EM or POU_D_TGM) requires to provide
additional information, compared to key words VALE and CARA, using the key words
AFFE_SECT and/or AFFE_FIBER [§12.3].
The objective is to check the coherence of the information (AIRE and INERTIE) provided on the one hand by
key word POUTRE and in addition by key words AFFE_SECT and AFFE_FIBER. The criterion
of error is based on the error relating and is compared either with the default value or to that given
by the user via key words PREC_AIRE and PREC_INERTIE.
If the criterion is not satisfied a fatal error is generated.
The relative error is calculated in the following way:
SURFACE (BEAM) - (SURFACE (AFFE_SECT) +AIRE (AFFE_FIBER))
----------------------------------------------- <= PREC_AIRE
SURFACE (BEAM)
INERTIA (BEAM) - (INERTIA (AFFE_SECT) +INERTIE (AFFE_FIBER))
---------------------------------------------------------- <= PREC_INERTIE
INERTIA (BEAM)
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Note:
· AIRE (AFFE_SECT) is calculated by making the sum of the surfaces of the elements defined in
grid, under key word MAILLAGE_SECT in operand AFFE_SECT.
· AIRE (AFFE_SECT) is calculated by making the sum of the surfaces of fibers defined in the operand
AFFE_FIBER.
· INERTIE (AFFE_SECT) is calculated by making the sum of S.D ² elements defined in
grid, under key word MAILLAGE_SECT in operand AFFE_SECT. (S: represent
surface of an element and D the distance between the center of gravity of the element and the axis defined by
key word CARA_AXE_POUTRE under operand AFFE_SECT).
· INERTIE (AFFE_FIBER) is calculated by making the sum of S.D ² fibers defined in
operand AFFE_FIBER. (S: represent the surface of a fiber and D the distance between fiber and
the axis defined by key word CARA_AXE_POUTRE under operand AFFE_FIBER).
Note:
When the section is defined by a grid (key word MAILLAGE_SECT under the operand
AFFE_SECT) the total calculation of the inertia of the surface whole of the elements does not hold account
inertia suitable for each element. It is thus necessary to define a sufficient number of fiber so that
this error is weak and remains lower than PREC_INERTIE.
For example a rectangular section cut out uniformly in the height in “N” elements
conduit with the following errors, on the values of inertias:
Cutting
2 3 4 5 6
Inertia error
25%
11.11% 6.25% 4.00% 2.77%
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10 Word
key
ORIENTATION
10.1 Characteristics
allocatable
This key word makes it possible to affect the orientations:
· principal axes of the cross sections of the elements of the beam type,
· discrete elements assigned to nodes or meshs of the type POI1 (discrete elements
nodal) or with meshs of the type SEG2 (discrete elements of connection).
Note:
There is always a local reference mark by defect attached to the elements of the type POUTRE or DISCRET
even if operand ORIENTATION is not used. It corresponds to ANGL_VRIL = 0 for
elements attached to a mesh SEG2 (beams or discrete) and ANGL_NAUT = (0., 0., 0.) for
nodal discrete elements,
For the elements of the type TUYAU, key word ORIENTATION allows to define a generating line
continue defining for each section the angular origin.
10.2 Syntax
ORIENTATION = (
_F (/
GROUP_MA
=
lgma,
[l_gr_maille]
/MAILLE
= lma
,
[l_maille]
/
GROUP_NO
=
lgno,
[l_gr_noeud]
/NOEUD
= lno
,
[l_noeud]
VALE =
langl,
[l_R]
CARA =/“VECT_Y”,
/“ANGL_VRIL”,
/“VECT_X_Y”,
/“ANGL_NAUT”,
/“GENE_TUYAU”,
CRITERION =/“RELATIVE”, [DEFECT]
/“ABSOLU”,
PRECISION
=
/
eps, [R]
/
1.E-4,
[DEFAUT]
),
)
10.3 Rules
of use
One can assign successively to the same mesh or the same node, several values
of orientation: the orientation finally taken is the composition of the orientations.
Example:
ORIENTATION= (
_F (CARA = ' ANGL_NAUT', VALE= (1., 1., 1.), MAILLE = “P1”),
_F (CARA = ' ANGL_VRIL', VALE = 45. , MAILLE = “M1”),
_F (CARA = ' ANGL_VRIL', VALE = 90. , MAILLE = “m2”),
)
· to define the local reference mark associated with a mesh of the type POI1 or a node (discrete element), it is necessary
to use either ANGL_NAUT, or VECT_X_Y,
· to define the local reference mark around the axis defined by a mesh SEG2 (beam or discrete), it is necessary
to use either ANGL_VRIL, or VECT_Y,
· to define a generating line on the elements pipe, GENE_TUYAU should be used.
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10.4 Operands
VECT_X_Y/ANGL_NAUT
/CARA = “ANGL_NAUT”, VALE = (,)
[V5.01.100]
The nautical angles, provided in degrees, are the angles making it possible to pass from the reference mark
total of definition of the co-ordinates of nodes (P, X, Y, Z) to the local reference mark (P, x2, y2, z2). This one
is obtained by 3 rotations:
· a rotation of angle around Z, transforming (P, X, Y, Z) in (P, x1, y1, Z) [Figure 10.4-a],
· a rotation of angle - around y1, transforming (P, x1, y1, Z) in (P, x2, y1, z1) [Figure 10.4-b],
· a rotation of angle around x2, transforming (P, x2, y1, z1) in (P, x2, y2, z2)
[Figure 10.4-c].
Y
Z
Y1
Z1
X1
X2
P
P
X
X1
Z
Y1
Appear 10.4-a
Appear 10.4-b
Z1
Z2
Y2
P
Y1
X2
Appear 10.4-c
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the local reference mark is: (P, x2, y2, z2)
Z
Z
Z
X
Z
Y
Y
P
Y1
Y
X
X1
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(L L L D D D
X, X, X, y, y, y
1
2
3
1
2
3)
/CARA = “VECT_X_Y”, VALE =
L
L
L
X, X, X
1
2
3 are the 3 components, in the total reference mark, of a vector defining the local axis X.
2
D
D
D
y, y, y
1
2
3 are the 3 components, in the total reference mark, of a vector D
y, of which projection
on the orthogonal level with X local axis Y. local axis Z will provide supplements the reference mark then for
2
2
2
that the trihedron (P, X, y, Z are direct [Figure 10.4-d].
2
2
2)
yd
y2
x2
P
Appear 10.4-d
10.5 Operand
ANGL_VRIL/VECT_Y
In the case of the meshs SEG2, axis X is already carried by the mesh (the direction of X is defined by
2
2
classification of two nodes of the mesh). It is thus enough to define y and Z, is by rotation around
2
2
X (key word
2
ANGL_VRIL) is by defining a vector (key word VECT_Y).
/CARA = “ANGL_VRIL”, VALE =
is the angle (in degrees) of rotation around X, transforming (P, X, y, Z in (P, X, y, Z.
2
2
2)
2
1
1)
2
D
D
D
/CARA = “VECT_Y”, VALE = y, y, y
1
2
3
D
D
D
y, y, y
1
2
3 are the 3 components of a vector D
y of which projection on the orthogonal level with X
2
the local axis y [Figure 10.4-d] will provide. Axis Z is such as (P, X, y, Z is direct.
2
2
2)
2
2
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10.6 Operand
“GENE_TUYAU”
Relate to only elements TUYAU (modelings TUYAU_3M or TUYAU_6M).
VALE = (Z1, Z2, Z3) then contains the 3 components of a vector Z directing the generator of the pipe
(continuous line traced on the pipe, defining for each element the origin of the angle used for
to express ovalization and warping).
This vector must be defined in a node or a GROUP_NO end of the pipe. The geometry is then
built automatically for all the related elements of TUYAU.
N2
generator
Z
N2
N1
U
ur
10.7 Operands
PRECISION/CRITERION
This precision is used for the construction of the generator like defining the limit enters
a right pipe section and an element curve (distinction based on the alignment of the 3 or 4 nodes
element).
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11 Word
key
DEFI_ARC
11.1 Characteristics
allocatable
Allows to assign to curved beams (POU_C_T) (elements with 2 nodes) of the characteristics related to
curvature of the element (radius of curvature and orientation of the plan of the arc). Those can be
defined in the choice by the key words: POIN_TANG, CENTER or (ORIE_ARC and RAYON).
11.2 Notice
The key words of DEFI_ARC are used to define the geometrical characteristics (radius of curvature and
plan of the elbow) of the curved element of beam. The principal reference mark of inertia is not defined here, and must
to be given as for the right beams by key word ORIENTATION (ANGL_VRIL/VECT_Y), in
supposing that the element is right (segment NR NR
I
J).
11.3 Syntax
DEFI_ARC = (
_F (
/
MAILLE
=
lma
,
[l_maille]
/
GROUP_MA
=
lgma,
[l_gr_maille]
/POIN_TANG
=
(xt
,
yt
,
zt),
[l_R]
/NOEUD_POIN_TANG
= No,
[node]
/GROUP_NO_POIN_TG
=
gno, [gr_noeud]
/
CENTER
=
(teststemxç
,
teststemyç
,
zc),
[l_R]
/NOEUD_CENTER
= No,
[node],
/
GROUP_NO_CENTER
=
gno, [gr_noeud]
/ORIE_ARC = arc,
[R]
RAYON
=
R,
[R]
/COEF_FLEX
=
cflex,
[R]
/
COEF_FLEX_XY
=
cflex_xy,
[R]
COEF_FLEX_XZ
=
cflex_xz,
[R]
/INDI_SIGM
=
isigm,
[R]
/
INDI_SIGM_XY
=
isigm_xy,
[R]
INDI_SIGM_XZ
=
isigm_xz,
[R]
PRECISION
=
/
eps, [R]
/
1.0E-03 [DEFAUT]
CRITERION =/“ABSOLUTE”,
/
“RELATIVE”, [DEFECT]
),
)
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11.4 Operands
POIN_TANG/NOEUD_POIN_TANG/GROUP_NO_POIN_TG
/POIN_TANG
= (xt, yt, zt)
/NOEUD_POIN_TANG
= “NT”
/GROUP_NO_POIN_TG
= “GNT”
The point of intersection T of the tangents defines in the arc in its two ends (intersection of
lines of diagram), either by its co-ordinates (xt, yt, zt) in the total reference mark, or by the name of
node located in this point (“NT”), is by the name of a group of nodes (“GNT”) container only one
node corresponding to this point.
Ni
T
Nj
C
11.5 Operands
CENTER/NOEUD_CENTER/GROUP_NO_CENTER
/CENTER
= (teststemxç, teststemyç, zc)
/NOEUD_CENTER
= “NC”,
/GROUP_NO_CENTER
= “GNC”,
The center of curvature C of the element defines. Angle (C, Nj, Ni) must be strictly lower than 2.
The point C is defined either by its co-ordinates (teststemxç, teststemyç, zc) in the total reference mark, or by the node
located out of C given by its name (“NC”) or by the name of a group (“GNC”) containing only it
node.
11.6 Operands
PRECISION/CRITERION
The precision for the checking defines that C is well the center of the arc of circle NR NR
I
J:
C NR - C NR
I
J < eps
(CRITERE:“ABSOLU”)
C NR - C NR < eps C NR
I
J
I
(CRITERE:“RELATIF”)
11.7 Operands
RADIUS/ORIE_ARC
ORIE_ARC
=
arc
Angle of orientation of the arc of the element (in degrees). The angle arc defines rotation around the axis
room xl (determined by the two ends of arc Ni and Nj) allowing to pass from (M, xl, y1, z1)
with (M, xl, yl, zl) [Figure 11.7-a].
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RADIUS = Rcourb
Radius of curvature of the element. It makes it possible to calculate the center C of the arc [Figure 11.7-b].
Z1
ZL
arc
YL
arc
M
Y1
XL
Appear 11.7-a
Zl
ZL
YL
Ni
Y1
arc
R
arc
court
M
B
Nj
XL
C
Appear 11.7-b
Note:
· the reference mark (M, xl, y1, z1) is calculated automatically starting from Ni, Nj, ends of
meshs belonging to lma or lgma, following the same principle as for the key word
ORIENTATION [Figure 10.4-a] and [Figure 10.4-b],
· the local axis yl is directed C towards Mr.
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11.8 Operand COEF_FLEX, COEF_FLEX_XZ, COEF_FLEX_XY: coefficients
of flexibility
COEF_FLEX
= cflex
COEF_FLEX_XZ
= cflex_xz
COEF_FLEX_XY
= cflex_xy
For the modeling of the elbows of pipings the representation by elements of beam
circular is insufficient to represent the flexibility of a thin hull. The coefficient of
flexibility corrects the geometrical data (geometrical moments of inertia) in accordance with
rules of construction. For example, rules RCC_M lead, to make the calculation of rigidity of
inflection with one geometrical moment of inertia:
Iy, Z (tube)
I
=
with cflex
y, Z
>.
1
cflex
A traditional value of cflex, for a piping thickness E and average radius Rmoy, is
65
.
1
E R
given by:
courb
cflex =
with
=
.
2
Rmoy
This value can be calculated directly in the command file (see test FORMA01A
for example).
I (tube)
y
I y = cflex_ xz
If 2 coefficients are given, one obtains:
I (tube)
I
Z
Z = cflex_ xy
By defect, cflex = cflex_xz = cflex_xy = 1 (not of modification of geometrical inertias).
11.9 Operands INDI_SIGM/INDI_SIGM_XZ/INDI_SIGM_XY: Index
of intensification of the constraints
INDI_SIGM
= isigm
INDI_SIGM_XZ
= isigm_xz
INDI_SIGM_XY
= isigm_xy
For the calculation of bending stresses in the curved elements of beams of section
tubular, one can take account of a coefficient of intensification due to ovalization.
The constraints are written then:
My. R
Mz. R
xx =
* isigm or
* isigm; with isigm 1.
Iy
Iz
If 2 indices are given, one a:
My. R
xx =
.isigm_ xz
Iy
Mz. R
or
xx =
.isigm_ xy
Iz
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11.10 Notice
It is possible to check the characteristics of the curved elements of beams (angle, radius of
curvature) in the file “messages” while giving INFO = 2.
11.11 Example of use
Piping comprising two elbows (problem of Hoovgaard resulting from the test SSLL101B).
0.
0.922
With
1.828
B
0.922
0.922
0.
2.75
Z
=
=
4 5
=
3
6
=
7
=
With
8
9
69
10
B
3.
11
2
12
y
13
=
14
=
=
15
=
1.96
=
X
1
· diameter external of the pipe: 0.185 m
· thickness of the pipe: 6.12 mm
· radius of curvature of the elbows: 0.922 m
The 2 elbows are formed of the elements:
· E3 (nodes 3 and 4) E4 (nodes 4 and 5)
· E9 (nodes 9 and 10) E10 (nodes 10 and 11)
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The values of (,) are:
STANDARD NAME ALPHA
BETA
E1
MECA_POU_D_T
0.000000E+00
- .900000E+02
E2
MECA_POU_D_T
0.000000E+00
- .900000E+02
E5
MECA_POU_D_T
0.900000E+02
0.000000E+00
E6
MECA_POU_D_T
0.900000E+02
0.000000E+00
E7
MECA_POU_D_T
0.900000E+02
0.000000E+00
E8
MECA_POU_D_T
0.900000E+02
0.000000E+00
E11 MECA_POU_D_T
0.000000E+00
0.000000E+00
E12 MECA_POU_D_T
0.000000E+00
0.000000E+00
E13 MECA_POU_D_T
0.000000E+00
0.000000E+00
E14 MECA_POU_D_T
0.000000E+00
0.000000E+00
E3
MECA_POU_C_T
0.900000E+02
- .675050E+02
E4
MECA_POU_C_T
0.900000E+02
- .224950E+02
E9
MECA_POU_C_T
0.675050E+02
0.000000E+00
E10 MECA_POU_C_T
0.224950E+02
0.000000E+00
CARA_ELE = AFFE_CARA_ELEM (
MODELE = model,
INFO = 2,
POUTRE = (
_F (GROUP_MA = “SEC_1”,
SECTION = “GENERAL”,
# right pipe
CARA = (“A”, “IZ”, “IY”, “AY”, “AZ”, “JX”, “EZ”, “EY”,
“RY”, “RZ”, “RT”),
VALE = (3.4390E-3, 2 * 1.3770E-5,
2 * 2.0, 2.7540E-5, 2 * 0., 3 * 1.),
),
_F (GROUP_MA = “SEC_2”,
# elbows
VALE = (3.4390E-3, 2 * 5.8870E-6,
2 * 2., 2.7540E-5, 2 * 0., 3 * 1.),
),
),
DEFI_ARC = (
_F (MAILLE = (“E9”, “E10”),
POIN_TANG = (0.0, 0.0, 0.0),
PRECISION = 1.E-3,
CRITERION = “RELATIVE”,
),
_F (MAILLE = (“E3”, “E4”),
CENTER = (0., - 1.8280, - 0.9220),
PRECISION = 1.E-3,
CRITERION = “RELATIVE”,
),
),
)
The computed values by AFFE_CARA_ELEM are:
MOT CLE FACTEUR “DEFI_ARC” (meshs E 9e10)
KEY WORD “NETS”, RCOURB: 0.9219999999999899
KEY WORD “NETS”, ORIE_ARC: 0.
KEY WORD “NETS”, ANGLE_ARC: 90.
KEY WORD “NETS”, CENTER: 0.921999999999864, - 0.921999999999864, 0.
MOT CLE FACTEUR “DEFI_ARC” (meshs E 3e4)
KEY WORD “NETS”, RCOURB: 0.9219999999999828
KEY WORD “NETS”, ORIE_ARC: 90.
KEY WORD “NETS”, ANGLE_ARC: 90.00000000000091
KEY WORD “NETS”, CENTER: 0., - 1.82799999999996, - 0.92199999999997
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12 Words
keys
AFFE_SECT/AFFE_FIBER
12.1 Syntax
AFFE_SECT = (
_F (
NOM
=
nomsect [TXM]
/GROUP_MA
=
(“GMA1”, “GMA2”,…), [l_gr_maille]
/
MAILLE
=
(“MA1”, “MA2”,…),
[l_maille]
MAILLAGE_SECT
=
MASEC1, [grid]
COOR_AXE_POUTRE
=
(yg, zg,)
[l_R]
/TOUT_SECT
=
“OUI”,
/GROUP_MA_SECT
=
(“g1”, “g2”,…)
[l_gr_maille]
/
MAILLE_SECT
=
(“m1”, “m2”,…)
[l_maille]
),
),
AFFE_FIBER = (
_F (
NOM
=
nomsect [TXM]
/GROUP_MA
=
(“GMA1”, “GMA2”,…)
[l_gr_maille]
/
MAILLE
=
(“MA1”, “MA2”,…) [l_maille]
COOR_AXE_POUTRE
=
(xg, yg,), [l_R]
CARA =/“SURFACE”, [DEFECT]
/“DIAMETRE”,
VALE =
(
x1, y1, a1,
x2, y2, a2,
.. .,
xn
,
yn
, year
,)
[l_R]
),
)
Key words used to define the section of the multifibre beams, (modelings POU_D_EM or
POU_D_TGM) either using a grid (AFFE_SECT) or fiber by fiber (AFFE_FIBER).
12.2 Drank
Within the framework of a modeling of the multifibre type, there are two “levels” of modeling. It there with
modeling known as “longitudinal” which will be represented by a beam (geometrical support SEG2)
and a modeling planes section (perpendicular to the SEG2). Key word AFFE_SECT
allows to associate a plane grid of section (read beforehand by operator LIRE_MAILLAGE)
an element beam. AFFE_FIBER makes it possible to describe the section in the form of specific surfaces.
Note:
It may be that in modeling section planes, several materials cohabit. By
example, in a section concrete reinforced, there are at the same time concrete and reinforcements. In this case,
operator CREA_MAILLAGE allows to duplicate support SEG2 so that there is one
material by support. (see for example test SSNL119 [V6.02.119]).
Caution:
The information given in AFFE_SECT or AFFE_FIBER, makes it possible to calculate some
integrated characteristics of the cross-sections (surface, moments static and quadratic).
In spite of that, it is necessary to give coherent values for operands A, IY, IZ
under key word POUTRE. A checking is carried out on the coherence of these sizes. If
the relative error is too important (Cf. key words PREC_AIRE, PREC_INERTIE) a fatal error
is emitted.
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12.3 Words
keys
AFFE_SECT and AFFE_FIBER
/AFFE_SECT
/AFFE_FIBER
The entities of the grid of beams concerned and the sections define which are to them
affected. Key word AFFE_SECT makes it possible to affect a section defined by a plane grid
(the elements of this grid are the sections of fibers) and key word AFFE_FIBER allows
to affect a section where the fibers are defined by points.
The rule of overload applies between several occurrences of the key words factors
AFFE_SECT or AFFE_FIBER [U1.03.00].
12.3.1 Operands commun runs with AFFE_SECT and AFFE_FIBER
/MAILLE
/GROUP_MA
These operands make it possible to define the entities of the grid of beams (elements SEG2) which
are concerned with the occurrence of the key word factor:
Operands
Contents/Significance
MAILLE
Assignment with a list of meshs
GROUP_MA
Assignment with a list of groups of meshs
COOR_AXE_POUTRE = (yg, zg)
This operand makes it possible to define the co-ordinates of the neutral axis of the beam in the reference mark of
cross-section: integrations (static moments or of inertias) will be made compared to this
center. The position (0. 0.) corresponds at the origin of the co-ordinates used for the grid
surface in the case of AFFE_SECT or in the beginning chosen to define the co-ordinates
data using operand VALE in the case of AFFE_FIBER.
Z
G
zg
O
yg
y
NOM
This operand makes it possible to define a name for the cross-section (8 characters). This name is pointed out
in the messages concerning this cross-section (see operand INFO).
If NOM is not used under AFFE_SECT, the name of the section (allotted automatically) is
“SECT_i” where I is the ième occurrence of AFFE_SECT in the data file. The same if NOM
is not used under AFFE_FIBER, the name of the automatic section is “PONCT_j” where J is
jème occurrence of AFFE_FIBER in the data file.
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12.3.2 Operands specific to AFFE_SECT
MAILLAGE_SECT
Name of the plane “grid” which contains the “description of the section”.
By “grid”, one understands a whole of triangular meshs with 3 nodes and/or quadrilaterals with 4
nodes.
By “description of the section”, one understands part of this “grid” specified by one of
operands TOUT_SECT, MAILLE_SECT or GROUP_MA_SECT. Each mesh represents
section of a fiber.
/TOUT_SECT
/MAILLE_SECT
/GROUP_MA_SECT
Operands
Contents/Significance
TOUT_SECT
The section is defined by the totality of the meshs of the grid defined under
MAILLAGE_SECT
MAILLE_SECT
The section is defined by a list of meshs
GROUP_MA_SECT
The section is defined by a list of groups of meshs
Note:
· Since it is not used as support with finite elements, the “grid” does not have obligatorily
to have a connectivity, it can be composed of a whole of juxtaposed meshs which
touch or do not touch themselves.
· All the meshs defined in the “description of the section” will have the same behavior,
that of the finite element of beam to which they are affected (see remark in §1).
· The co-ordinates y and Z of the plane grid of the section (y horizontal, Z vertical) are defined
in a plan perpendicular to the axis of the beam. This axis is defined using the operand
COOR_AXE_POUTRE. To define the angle of gimlet, i.e. the angle enters the axis there of the grid
plan of the section and the axis Y of the element beam, it is necessary to use key word ORIENTATION of
operator AFFE_CARA_ELEM (see example).
12.3.3 Operands specific to AFFE_FIBER
The cross-section of the element beam is defined by a whole of “specific” fibers.
CARA
Allows to specify if the third value given for each fiber is surface (by defect) or
the diameter (see VALE).
VALE
Each fiber is described by a triplet of values: y, Z and valley. It is necessary to give them
values according to this sequence, and there are as many triplets as of fibers.
· Y and Z are the co-ordinates of the center of fiber in a plan perpendicular to the axis of
beam. The position of the axis of the beam can be modified thanks to the operand
COOR_AXE_POUTRE. To give an angle of gimlet, operand ORIENTATION should be used.
· Valley is either the surface of a fiber, or the diameter of a cylindrical fiber.
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13 Word
key
DISCRET and DISCRET_2D
13.1 Characteristics
allocatable
These key words make it possible to assign directly to entities (meshs or nodes), which support
elements of the type DIS_T, DIS_TR (DISCRET) or 2d_DIS_T, 2d_DIS_TR (DISCRET_2D), of
matrices of rigidity, mass or damping.
On all the entities one can affect matrices corresponding to the degrees of freedom of translation
(T) only or with the degrees of freedom of translation and rotation (TR). The matrices can be
diagonals (D) or full. In this case, they are obligatorily symmetrical and one will only provide
triangular higher, with a convention of classification of the terms imposed (see examples).
The matrices can be affected:
· with nodes or meshs of the types POI1; they are then known as nodal matrices (NR),
· with meshs of the type SEG2; they are then known as matrices of connection (L).
In the event of assignment of matrices to meshs or nodes, the type of element DISCRET must be
affected, au préalable, with these meshs or these nodes by operator AFFE_MODELE [U4.41.01].
13.2 Syntax
DISCRET and DISCRET_2D = (
_F (/MAILLE
= lma
,
[l_maille]
/
GROUP_MA
=
lgma,
[l_gr_maille]
/NOEUD
= lno
,
[l_noeud]
/
GROUP_NO
=
lgno,
[l_gr_noeud]
# matrices
of
rigidity
/CARA
=
| “K_T_D_N' | “K_TR_D_N' | “K_T_D_L' | “K_TR_D_L',
| “K_T_N' | “K_TR_N' | “K_T_L' | “K_TR_L',
# matrices
of
mass
/CARA = | “M_T_D_N' | “M_TR_D_N',
| “M_T_N' | “M_TR_N' | “M_T_L' | “M_TR_L',
# matrices
of damping
/CARA = | “A_T_D_N' | “A_TR_D_N' | “A_T_D_L' | “A_TR_D_L',
| “A_T_N' | “A_TR_N' | “A_T_L' | “A_TR_L',
VALE = lva, [l_R]
REPERE
=/“LOCAL”,
/
“GLOBAL”,
[DEFAUT]
AMOR_HYST
=
/
0.0, [DEFAUT]
/
amnh,
[R]
),
)
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13.3 Operands
13.3.1 Rules of use
· RIGIDITE or AMORTISSEMENT
CARA CARA
ENTITE
DIS_ *
2d_DIS_ *
VALE
VALE
“K_T_D_N' “A_T_D_N'
node or POI1
3 terms
2 terms
“K_T_D_L' “A_T_D_L'
SEG2
3 terms
2 terms
“K_TR_D_N' “A_TR_D_N'
node or POI1
6 terms
3 terms
“K_TR_D_L' “A_TR_D_L'
SEG2
6 terms
3 terms
“K_T_N' “A_T_N'
node or POI1
6 terms
3 terms
“K_T_L' “A_T_L'
SEG2
21 terms
10 terms
“K_TR_N' “A_TR_N'
node or POI1
21 terms
6 terms
“K_TR_L' “A_TR_L'
SEG2
78 terms
21 terms
· MASSE
CARA ENTITY
DIS_ *
2d_DIS_ *
VALE
VALE
“M_T_D_N'
node or POI1
1 (mass)
1 (mass)
“M_TR_D_N'
node or POI1
10 (mass/inertia)
nonavailable
“M_T_N'
node or POI1
6 (mass/inertia)
3 (mass/inertia)
“M_T_L' SEG2 21 (mass/inertia)
10 (mass/inertia)
“M_TR_N'
node or POI1
21 (mass/inertia)
6 (mass/inertia)
“M_TR_L' SEG2
78 (mass/inertia)
21 (mass/inertia)
13.3.2 Operands K_ (matrices of rigidity) or A_ (matrices of damping)
K_T_D_N/A_T_D_N
for a mesh of the type POI1 or a node, one finds in correspondence in VALE 3 Kx values,
Ky, Kz in DIS_T and 2 Kx values, Ky in 2d_DIS_T such as:
U U U
X
y
Z
U U
X
y
K
0
0
X
Kx
0
K
=
or A =
0
K
K or A
y
0
0
K
y
0
0
K
Z
K_T_D_L/A_T_D_L
for a mesh of the type SEG2, K being the matrix previously definite:
Noeud1 Noeud2
K
- K
- K
K
it is thus enough to provide the 3 values Kx, Ky and Kz.
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:
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K_TR_D_N/A_TR_D_N
for a mesh of the type POI1 or node, one finds in correspondence in VALE 6 values Kx, Ky,
Kz, KRx, KRy, KRz in DIS_TR or 3 Kx values, Ky, KRz in 2d_DIS_TR such as:
U U U R R R
X
y
Z
X
y
Z
K
0
X
0
0
0
0
U U R
X
y
Z
0
K
y
0
0
0
0
K
0
0
X
0 0
K
K or A =
Z
0
0
0
0
K
0
K or A
y
=
0
0
0
KR
0
0
0
0
X
KR
Z
0
0
0
0
KR
0
y
0
0
0
0
0
KR
Z
K_TR_D_L/A_TR_D_L
for a mesh of the type SEG2, K being the matrix previously definite:
Noeud1 Noeud2
K
- K
- K
K
it is enough to give the 6 values above.
K_T_N/A_T_N
for a mesh of the type POI1 or a node, one finds in correspondence in VALE 6 K1 values,
K2,… K6 in DIS_T or 3 K1 values, K2, K3 in 2d_DIS_T such as:
U U U
X
y
Z
U U
X
y
K
K
K
1
2
4
K
K
1
2
K
=
or A =
K
K
K or A
3
5
K
3
K
6
K_T_L/A_T_L
for a mesh of the type SEG2, one finds in correspondence in VALE 21 values K1, K2,…, K21
in DIS_T or 10 K1 values, K2,… K10 in 2d_DIS_T and stamps it following rigidity will be
affected:
U U U U
U
U
x1
y1
z1
x2
y2
z2
U U U
U
K
K
K
K
K
K
x1
y1
z2
y2
1
2
4
7
11
16
K
K
K
K
K
K
K
K
K
1
2
4
7
3
5
8
12
17
K or A =
K
K
K
K
K
K
K
3
5
8
K or A
6
9
13
18
=
K
K
K
K
K
6
9
10
14
19
K
K
K
10
15
20
K
21
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:
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K_TR_N/A_TR_N
for a mesh of the type POI1 or a node, one finds in correspondence in VALE 21 K1 values,
K2,…, K21 in DIS_TR or 6 values K1, K2,… K6 in 2d_DIS_TR such as:
U U U R R R
X
y
Z
X
y
Z
K
K
K
K
K
K
1
2
4
7
11
16
U U R
K
K
K
K
K
X
y
Z
3
5
8
12
17
K
K
K
K
K
K
K
1
2
4
6
9
13
18
K or A =
K or A =
K
K
K
K
K
3
5
10
14
19
K
K
K
6
15
20
K
21
K_TR_L/A_TR_L
for a mesh of the type SEG2, one finds in correspondence in VALE 78 values K1, K2,…, K78
in DIS_TR.
U U U R R R
U
U
U
R R
R
x1
y1
z1
x1
y1
z1
x2
y2
z2
x2
y2
z2
K
K
K
K
K
K K
K
K
K
K
K
1
2
4
7
11
16
22
29
37
46
56
67
K
K
K
K
K K
K
K
K
K
K
3
5
8
12
17
23
30
38
47
57
68
K
K
K
K
6
9
13
18 K
K
K
K
K
K
24
31
39
48
58
69
K
K
K
10
14
19 K
K
K
K
K
K
25
32
40
49
59
70
K
K
15
20 K
K
K
K
K
K
26
33
41
50
60
71
K
21 K
K
K
K
K
K
27
34
42
51
61
72
K or A =
K
K
K
K
K
K
28
35
43
52
62
73
K
K
K
K
K
36
44
53
63
74
K
K
K
K
45
54
64
75
K
K
K
55
65
76
K
K
66
77
K
78
or 21 values K, K,…, K in 2d_ DIS_ TR such as:
1
2
21
U U R U
U
R
x1
y1
z1
x2
y2
z2
K
K
K
K
K
K
1
2
4
7
11
16
K
K
K
K
K
3
5
8
12
17
K
K
K
K
K
6
9
13
18
or A =
K
K
K
10
14
19
K
K
15
20
K21
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13.3.3 Operands M_ Matrices of mass
M_T_D_N
for a mesh of the type POI1 or a node, one finds in correspondence in VALE a value Mr.
The matrix of following mass will be affected:
U U U
X
y
Z
m 0 0
M =
0 m
0
0 0 m
M_TR_D_N (nonavailable in 2d_DIS_TR)
for a mesh of the type POI1 or a node, one finds in correspondence in VALE a value of
mass m, 6 values of the tensor of inertia (mass): I, I, I, I, I, I
xx
yy
zz
xy
yz
xz, and 3 components
vector of eccentricity of the mass compared to its node: E, E, E
X
y
Z. The matrix of mass
following will be affected:
U
2
2
X
U
y
U
Z X-ray Ry Rz
Vxx = I xx +m (ez +ey)
m
0
0
0
- me
2
2
Z
me
y
Vyy = I yy +m (ex +ez)
m
0
me
Z
0
- mex
V
2
2
zz = I zz +m (E y +ex)
M =
m
- me
y
me
X
0
Vxy = I xy - m E
X E
y
V
xx
V
xy
V
xz
V
yz = I yz - m E
y E
Z
V
yy
V
yz
V
V
xz = I xz - m E
X E
Z
zz
Z
y
G
Node
X
Caution:
The eccentricity must be expressed in the total reference mark: co-ordinates of vector NG (eccentricity)
directed node towards the mass.
M_T_N
for a mesh of the type POI1 or node, one finds in correspondence in VALE 6 values M1, m2,
…, M6 in DIS_T or 3 M1 values, m2, m3 in 2d_DIS_T and stamps it of following mass will be
affected:
U U U
X
y
Z
U U
M
M
M
X
y
1
2
4
M
M
1
2
M =
M
M
M
3
5
=
M
3
M
6
See for example test SDLD27 [V2.01.027].
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M_TR_N
for a mesh of the type POI1 or node, one finds in correspondence in VALE 21 M1 values,
M2,…, M21 in DIS_TR or 6 values M1, m2,…, M6 in 2d_DIS_TR and stamp it of mass
following will be affected:
U U U R R R
X
y
Z
X
y
Z
M
M
M
M
M
M
1
2
4
7
11
16
U U R
M
M
M
M
M
X
y
Z
3
5
8
12
17
M
M
M
M
M
M
M
1
2
4
6
9
13
18
M =
M =
M
M
M
M
M
3
5
10
14
19
M
M
M
6
15
20
M
21
M_T_L
for a mesh of the type SEG2, one finds in correspondence in VALE 21 values M1, m2,…, M21
in DIS_T or 10 M1 values, m2,…, M10 in 2d_DIS_T and stamp it of following mass will be
affected:
U U U U
U
U
x1
y1
z1
x2
y2
z2
M
M
M
M
M
M
1
2
4
7
11
16
U U U
U
x1
y1
x2
y2
M
M
M
M
M
M
M
M
M
3
5
8
12
17
1
2
4
7
M
M
M
M
M
M
M
M
6
9
13
18
=
M
3
5
8
=
M
M
M
M
10
14
19
6
M9
M
M
15
20
M
10
M
21
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M_TR_L
for a mesh of the type SEG2, one finds in correspondence in VALE 78 values M1, m2,…, M78
in DIS_TR and the matrix of following mass will be affected:
U U U R R R U
U
U
R R R
x1
y1
z1
x1
y1
z1
x2
y2
z2
x2
y2
z2
M
M
M
M
M
MR. M
M
M
M
M
M
1
2
4
7
11
16
22
29
37
46
56
67
M
M
M
M
MR. M
M
M
M
M
M
3
5
8
12
17
23
30
38
47
57
68
M
M
M
MR. M
M
6
9
13
18
24
31
M
M
M
M
39
48
58
69
M
M
M
10
14
19 M
M
M
M
M
M
25
32
40
49
59
70
M
M
15
20 M
M
M
M
M
M
26
33
41
50
60
71
MR. M
M
M
M
M
M
M
21
=
27
34
42
51
61
72
M
M
M
M
M
M
28
35
43
52
62
73
M
M
M
M
M
36
44
53
63
74
M
M
M
M
45
54
64
75
M
M
M
55
65
76
M
M
66
77
M
78
or 21 values M,
M
…,
M
in
1
2
21
2D_ DIS_ TR
U U R U
U
R
x1
y1
z1
x2
y2
z2
M
M
M
M
M
M
1
2
4
7
11
16
M
M
M
M
M
3
5
8
12
17
M
M
M
M
M =
6
9
13
18
M
M
M
10
14
19
M
M
15
20
M21
Note:
Two options M_T_L and M_TR_L do not correspond in general to an option of modeling
having a mechanical significance. They are usable to only import in Aster of
matrices of masses discretized on a mesh of the type SEG2 by another software. Indeed, one
affect usually values of specific mass and inertia (mesh POI1) by M_T_D_N or
M_TR_D_N.
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13.3.4 Operand AMOR_HYST
AMOR_HYST = amor_h,
Allows to assign to a discrete element a coefficient to build a matrix of rigidity
complex (hysteretic modeling of damping) the built matrix is:
(1+
)
J
amor_ H K
where K is the K_ matrix * whose values are provided in the same occurrence of the key word
DISCRET. The matrix of rigidity complexes will be actually built at the time of a call to
CALC_MATR_ELEM [U4.61.01] with option AMOR_HYST (see test SDLD313) and [R5.05.04].
13.3.5 Operand LOCATES
REPERE
=/“LOCAL”,
/“GLOBAL”,
By defect the values of the matrices provided for the discrete elements are used for
to express the corresponding quantities in REPERE = “GLOBAL”.
If one wishes to define a particular reference mark in a node (or nets of type POI1) one will specify
REPERE = “LOCAL” by defining this reference mark by key word ORIENTATION [§10].
For a matrix defined on a mesh of the type SEG2 the operand REPERE = “LOCAL” allows
to refer to the local reference mark attached to the mesh (initial node, final node) supplemented if necessary
of an angle of gimlet defined by key word ORIENTATION [§10].
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14 Word
key
MASSIF
14.1 Characteristics
allocatable
Allows to assign to elements 3D or 2D of the local axes (which can for example be used
to define directions of orthotropism (cf DEFI_MATERIAU [U4.43.01])). These local axes are
defined by the key words:
· ANGL_REP (3 nautical angles) or (ANGL_AXE and ORIG_AXE) in 3D,
· ANGL_REP (1 only angle) in 2D.
14.2 Syntax
MASSIF = (
_F (
/
MAILLE
=
lma
,
[l_maille]
/
GROUP_MA
=
lgma,
[l_gr_maille]
/ANGL_REP = (,),
[l_R]
/ANGL_AXE = (,),
[l_R]
ORIG_AXE
=
(x1
,
x2
,
x3),
[l_R]
),
)
14.3 Operand
ANGL_REP
are the 3 nautical angles (as for the key word ORIENTATION, cf [§10]) defining the axes
buildings (X, y, Z), which correspond to the reference mark of orthotropism (L, T, NR). In 2D, it is necessary to only give,
what defines reference mark (LT) in the plan.
14.4 Operands
ANGL_AXE/ORIG_AXE
These key words are to be given in 3D only to define local axes for which one will use
a property of symmetry of revolution, or transverse isotropy (for example: structure with symmetry
cylindrical orthotropic).
ANGL_AXE = (,) defines the axis of revolution x1, (,) being the first two nautical angles,
ORIG_AXE = (x1, x2, x3) defines a O1 point of the axis.
Z
x1
O1
0
B
y
has
X
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15 Word
key
ASSE_GRIL
15.1 Syntax
ASSE_GRIL = (
_F (
/
GROUP_MA
=
lgma,
[l_gr_maille]
/
MAILLE
=
lma, [l_maille]
CARA = | “K_TR_D_N' | “K_TR_D_L_T' | “K_TR_D_L_N',
VALE =
lva
,
[l_R]
PAS_T
=
Pt,
[R]
PAS_N
=
pn
,
[R]
COEF_ECHELLE = ech
,
[R]
ANGL_REP
=
l_ang,
[l_R]
),
)
15.2 Characteristics
allocatable
This key word factor makes it possible to define the characteristics of rigidity of the finite element (quadrangle in
four nodes) associated modeling “ASSE_GRIL” (cf orders AFFE_MODELE [U4.41.01]).
This modeling relates to the representation of the grids of the fuel assemblies, by one
technique of homogenization. It must be associated modeling “ASSE_GRIL”, allowing
to model by homogenization a network, periodical of beams, bathed in a fluid
incompressible (cf [R4.07.05], cf key word factor POUTRE_FLUI).
15.3 Operand
GROUP_MA/MESH
Place of employment of the elementary characteristics:
· list the meshs (key word MAILLE),
· list groups of meshs (key word GROUP_MA).
15.4 Operand
ANGL_REP
ANGL_REP = (,)
A reference mark (L, T, NR) is associated each mesh. The direction L is the direction perpendicular to the plan
means of the mesh.
The angles in degree (,) make it possible to define compared to the reference mark of reference the vector to
to project on the average level of the mesh and which will indicate the direction T (as for key word COQUE,
operand ANGL_REP [Figure 8.3.3-c]).
15.5 Operand
PAS_T/PAS_N/COEF_ECHELLE
These operands define the geometrical characteristics of the characteristic periodic cell
grid. COEF_ECHELLE defines the coefficient of homothety making it possible to transform the cell
periodical real in the basic periodic cell with which the homogenized coefficients are
calculated.
PAS_T and PAS_N define dimensions of the rectangular basic cell along the axes T, NR
local reference mark.
15.6 Operands
CARA/VALE
These operands make it possible to define all rigidities of the springs associated with this modeling
(HI-75/96/074/0).
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NR
RT
RO
RO
R
R
NR
NR
PAS_N
RT
T
. R
R
O
O
L
PAS_T
CARA = “K_TR_D_L_T'
(kTL, kTT, kTN, CTL, CTT, CTN
D
D
D
D
D
D
)
VALE =
Differential rigidities (3 in translation, 3 in rotation) common to springs RT, relative to
directions L, T, NR.
CARA = “K_TR_D_L_N'
NL
NT
NR
NL
NT
NR
VALE = (K
, K
, K
, C
, C
, C
D
D
D
D
D
D
)
Differential rigidities (3 in translation, 3 in rotation) common to springs RN, relative to
directions L, T, NR.
CARA = “K_TR_D_N'
(*, *, *, CL, CT, CN
L
L
L)
VALE =
Local rigidities (3 in rotation) common to the Ro springs. 3 rigidities in translation are
been unaware of.
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16 Word
key
POUTRE_FLUI
16.1 Syntax
POUTRE_FLUI = (
_F (
/
GROUP_MA
=
lgma,
[l_gr_maille]
/
MAILLE
=
lma, [l_maille]
B_T
=
LT,
[R]
B_N
=
bn,
[R]
B_TN =
btn, [R]
A_FLUI
=
aflui,
[R]
A_CELL
=
acell,
[R]
COEF_ECHELLE = ech
,
[R]
),
)
16.2 Characteristics
allocatable
This key word factor makes it possible to define the characteristics of the finite elements (hexahedron in 8 or 20
nodes) associated modeling “3d_FAISCEAU” (cf orders AFFE_MODELE [U4.41.01]). This
modeling relates to the representation of a periodic network of tubes bathed by a fluid
incompressible (cf [R4.07.05]). An example is given in test SDLV111 [V2.04.111].
16.3 Operand
GROUP_MA/MESH
Place of employment of the elementary characteristics:
· list the meshs (key word MAILLE),
· list groups of meshs (key word GROUP_MA).
16.4 Operands
A_FLUI/A_CELL/COEF_ECHELLE
The periodic cell of the medium to be homogenized
is two-dimensional.
NR
The basic periodic cell which is used to calculate
the homogenized coefficients is obtained by
homothety starting from the periodic cell
Tube
real of the medium.
Fluid
L
T
A_FLUI: surface of the part occupied by the fluid in the basic periodic cell
A_CELL: surface of the basic periodic cell
COEF_ECHELLE: coefficient of homothety allowing to transform the real periodic cell into
basic periodic cell
16.5 Operands B_T/B_N/B_TN
Homogenized coefficients of the problem fluid-structure calculated in the reference mark (T, NR) [R4.07.05].
The orientation of this reference mark is fixed by the key word factor ORIENTATION. The direction L is inevitably
parallel with the beam axis of tubes.
Handbook of Utilization
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Titrate:
Operator AFFE_CARA_ELEM
Date:
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:
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17 Word
key
GRILL
17.1 Syntax
GRILL = (
_F (
/
MAILLE
=
lma, [l_maille]
/
GROUP_MA
=
lgma,
[l_gr_maille]
SECTION =
S1,
[R]
/ANGL_REP = (,)
[l_R]
/
ORIG_AXE
=
(xr,
yr,
Zr)
[l_R]
AXE = (vx,
vy,
vz)
[l_R]
EXCENTREMENT
= ez,
[R]
GRILL_NCOU
=
/
ncou,
[I]
/
1
[DEFAUT]
COEF_RIGI_DRZ
=/kz,
[R]
/
1.E-10, [DEFAUT]
),
)
17.2 Characteristics
allocatable
Allows to define characteristics of a lattice (modeling of tablecloth of reinforcements for the hulls
out of reinforced concrete) (see for example test SSNS100 [V6.05.100]), affected with modelings GRILL or
GRILL_MEMBRANE.
These characteristics are used to define an element of plate orthotropic, usable only, or more
often superimposed with an element of concrete plate.
17.3 Description of the operands
The following geometrical data are necessary to model the tablecloth of reinforcements:
· EXCENTREMENT = ez: offsetting ez (constant for all the nodes of the mesh) of
tablecloth of reinforcements compared to the mesh support (distance measured on the normal of
net support), (modeling GRILL only).
· SECTION = S1: section of the reinforcements in direction 1.
· ANGL_REP = to see key word COQUE [§8]. This key word makes it possible to define the reference axis (x1). It
also defined the reference mark in which the deformations are calculated, constraints, curvatures,…
· COEF_RIGI_DRZ = to see key word COQUE [§8].
· ORIG_AXE, AXE = in the case of a cylindrical hull, these key words make it possible to define
the angle of the reinforcements, constant in a cylindrical reference mark in the following way: if D is
straight line passing by the point x0 (of co-ordinates xr yr Zr) and from axis V (vx vy vz) then in all
not X of the hull, the vector Y = V X
1
1 directs the reinforcements in X (with
X
XX, X
1 =
D
D projection of X on D).
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Plate
Reinforced concrete
Z1
Y1
Concrete
X1
T
ez
brace diameter 2
average layer
average layer
brace diameter
Equivalent tablecloth of reinforcements
1
Appear 17.3-a: Représentation of the reinforcements by an equivalent tablecloth
To define a grid or the section of the reinforcements in the longitudinal direction and the transverse one are
different, it is necessary to create 2 layers of elements (command CREA_MAILLAGE, key word CREA_GROUP_MA),
a layer of element for the longitudinal direction and a second layer of elements for
transverse direction:
GRILL= (
_F (
GROUP_MA = “GEOL”,
SECTION = 0.02,
ANGL_REP = (0.0, 0.0,),
EXCENTREMENT = 0.0,
),
_F (
GROUP_MA = “GEOT”,
SECTION = 0.01,
ANGL_REP = (90.0, 0.0,),
EXCENTREMENT = 0.01,
),
)
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18 Word
key
RIGI_PARASOL
18.1 Syntax
RIGI_PARASOL = (
_F (
# Groups of meshs which make the foundation raft
GROUP_MA
=
l_gma,
[l_group_ma]
GROUP_MA_POI1
=
l_gma,
[l_group_ma]
# Functions of distribution
/
FONC_GROUP =
l_fg, [l_fonction]
/
COEF_GROUP =
l_cg, [l_R]
# Total Stiffnesses to distribute
CARA =/“K_TR_D_N' | “K_T_D_N',
/“A_TR_D_N' | “A_T_D_N',
[l_TXM]
VALE = l_val, [l_R]
LOCATE =/“LOCAL”,
/
“GLOBAL”,
[DEFAUT]
# Center revolves
/
GROUP_NO_CENTER
=
gno,
[group_no]
/
NOEUD_CENTER
=
Nd,
[node]
/
COOR_CENTER
=
l_xyz,
[l_R]
# Specific Meshs corresponding to the nodes of the foundation raft
/
GROUP_MA_POI1
=
gmapoi1, [group_ma]
),
)
18.2 Characteristics
allocatable
This functionality corresponds to a methodology used by the SEPTEN to determine them
characteristics of discrete elements (springs of translation and/or rotation) to apply to the nodes
of a foundation raft starting from results obtained by code PARASOL.
One must affect modeling “DIS_TR” or “DIS_T' on the group of nodes which make it up
to erase.
The meshs which make the foundation raft (pertaining to the l_gma groups) carry when to them one
modeling of plate (DKT, DST) cf test SDLS108 [V2.03.108] or a modeling of face of 3D.
18.3 Description of the operands
· GROUP_MA: list groups of meshs which make the foundation raft.
· GROUP_MA_POI1: list groups of points including/understanding the nodes of the groups of meshs
surface defined by GROUP_MA. That makes it possible to declare the nodes of a foundation defined by
surface meshs like specific meshs POI1 in order to affect the characteristics to them
RIGI_PARASOL what makes it possible to affect materials or behaviors to them for
the use of a nonlinear operator. If it is not present, the nodes are regarded as
late meshs for a strictly linear study for example.
· FONC_GROUP/COEF_GROUP: list real functions or coefficients. There are as many arguments
in this list that there are groups of meshs which make the foundation raft (definite under the key word
GROUP_MA). The functions must have as a X-coordinate the distance to the center of gravity (key word
defined by GROUP_NO_CENTER/NOEUD_CENTER/COOR_CENTER).
· The total stiffnesses of ground, resulting from code PARASOL are provided by the user using
key words CARA and VALE as for the discrete elements. One can also select nature
reference mark (total or local) in which one defines the characteristics of the springs (key word
REPERE). Stiffnesses or the depreciation only defined in translation can
also to be distributed (K_T_D_N or A_T_D_N, not stiffness in rotation), in this case it is
only necessary to give 3 values behind VALE = (kx, ky, kz).
· To define the center of the foundation raft (calculated by code PARASOL), one can is to give them
co-ordinates (three realities given behind key word COOR_CENTER), is to give the name of a node
Handbook of Utilization
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grid (for more facility, one accepts also the name of a group of nodes but this one
must contain that only one node: key word GROUP_NO_CENTER or NOEUD_CENTER).
· GROUP_MA_POI1 makes it possible to specify a group of specific meshs containing the nodes of
groups of surface meshs (to erase) definite under GROUP_MA. On these nodes of foundation, one
will be able to affect various behaviors materials for the use by an operator not
linear.
18.4 Principle of determination of the characteristics of the elements
discrete [R4.05.01]
One represents the foundation raft by a whole of surface elements of center of gravity O. À l' aide de it
code PARASOL, one obtains 6 total sizes which characterize the coupling ground-foundation raft: three stiffnesses
of Kx translation, Ky, Kz and three stiffnesses of rotation Krx, Kry, Krz.
In each node of the grid of the foundation raft, Code_Aster seeks the characteristics in stiffness of one
discrete element of type K_TR_D_N (kx, ky, kz, krx, kry, krz) cf [R4.05.01].
To determine the stiffnesses of translation, one forces that they are proportional to surface
represented by the node and with a function of distribution depending on the distance to the center of gravity
foundation raft. That is to say S (P) the surface attached to the node P and F (R) the function of distribution where R is the distance
node P with the node O.
For the stiffnesses of rotation, one distributes the remainder (what remains after having removed the contributions
had with the translations) in the same way that translations.
If one calculates the efforts and the moments resulting at the point O due to the distribution from the springs in
each node of the grid of the foundation raft and if one identifies them with the values obtained by PARASOL, one
obtains the following formulas:
K = K/S
X
X
(p) F (COp); K (P) = K S
X
X
(p) F (COp)
P
K = K/S
y
y
(p) F (COp); K (P) = K S
y
y
(p) F (COp)
P
K = K/S
Z
Z
(p) F (COp); K (P) = K S
Z
Z
(p) F (COp)
P
2
2
Kr = Kr -
+
/
;
=
X
X
(kz (P) y K
COp
y (P) zOP)
S (P) F (COp) krx (P) Kr S
X
(P) F (COp)
P
P
2
2
Kr = Kr -
+
/
;
=
y
y
(kx (P) Z K
COp
Z (P) xOP)
S (P) F (COp) kry (P) Kr S
y
(P) F (COp)
P
P
2
2
Kr = Kr -
+
/
;
=
Z
Z
(kx (P) y K
COp
y (P) xOP)
S (P) F (COp) krz (P) Kr S
Z
(P) F (COp)
P
P
Notice 1:
Calculation of the area attached to the point P.
For each surface mesh of the foundation raft, one calculates surface, one divides it by the number of nodes
mesh and one affect this contribution to each node of the mesh. One ensures then:
S
= S (P)
to erase
P
Handbook of Utilization
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Notice 2:
It is considered that one can apply the same formulas to carry out a distribution of elements
discrete of damping.
18.5 Example
of use
carac = AFFE_CARA_ELEM (
RIGI_PARASOL =
_F (GROUP_MA = to erase,
COEF_GROUP = 2.,
CARA = (“K_TR_D_N', “A_TR_D_N'),
VALE = ((16 realities), (6 realities)),
NOEUD_CENTER = “P1”,
),
)
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19 Word
key
RIGI_MISS_3D
19.1 Syntax
RIGI_MISS_3D = (
_F (GROUP_MA_POI1
=
l_gma,
[l_group_ma]
GROUP_MA_SEG2
=
l_gma,
[l_group_ma]
FREQ_EXTR
=
freq,
[R]
UNITE_RESU_IMPE
=
/
links,
[I]
/30,
[DEFAUT]
),
)
19.2 Characteristics
allocatable
The use of this key word is dedicated to problems of separation of foundation in order to take
better the carpet of springs of ground counts some than RIGI_PARASOL does it which distributes 6 stiffnesses
total under a foundation proportionally on the surfaces of the elements surrounding its nodes.
This key word will affect the exact terms of a matrix of impedance calculated by MISS 3D for all them
ddl of interface (3 * a number of nodes) and for a frequency of extraction given. The assignment of these
terms (modeling “DIS_T') is then made with specific meshs POI1 nodes of the foundation
surface and possibly with the lines of the network of SEG2 superimposed on the foundation to represent
transverse connections between nodes.
19.3 Description of the operands
· GROUP_MA_POI1: Group specific meshs of the nodes of the foundation.
· GROUP_MA_SEG2: Group meshs of SEG2 connecting the nodes of the foundation transversely.
· FREQ_EXTR: Frequency of extraction of the matrix of impedance.
· UNITE_RESU_IMPE: Logical unit of the matrix of impedance calculated by MACRO_MISS_3D
option MISS_IMPE.
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