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Titrate:
Operators AFFE_CHAR_CINE and AFFE_CHAR_CINE_F

Date:
31/01/06
Author (S):
J. Key PELLET
:
U4.44.03-H1 Page:
1/8

Organization (S): EDF-R & D/AMA

Handbook of Utilization
U4.4- booklet: Modeling
Document: U4.44.03

Operators AFFE_CHAR_CINE
and AFFE_CHAR_CINE_F

1 Goal

To define a loading of the type “imposed degrees of freedom”.

This command can be used with a mechanical, thermal or acoustic model.
processing of these conditions “kinematics” will be done without dualisation and thus without addition of degrees of
freedom of Lagrange.

Attention this type of loading is not admitted by all the commands (for example
STAT_NON_LINE).

·
for AFFE_CHAR_CINE the affected values do not depend on any parameter and are
defined by actual values (mechanics or thermics) or complex values
(accoustics). These values can be null (blocking),
·
for AFFE_CHAR_CINE_F the affected values can be related to one (or several)
parameters to be chosen as a whole (INST, X, Y, Z).

Product a structure of data of the char_cine_ type *.
Handbook of Utilization
U4.4- booklet: Modeling
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Operators AFFE_CHAR_CINE and AFFE_CHAR_CINE_F

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2 Syntax
General

CH [char_cine_ *] = AFFE_CHAR_CINE




(
MODELE
=
Mo
,
[model]





/MECA_IMPO =


(see key word MECA_IMPO),






/THER_IMPO =


(see key word THER_IMPO),






/ACOU_IMPO =


(see key word MECA_IMPO),




)

if
MECA_IMPO
then [*]
MECA
if
THER_IMPO
THER
if
ACOU_IMPO
ACOU

CH [char_cine_ *] = AFFE_CHAR_CINE_F




(
MODELE
=
Mo
,
[model]





/MECA_IMPO =


(see key word MECA_IMPO),






/
THER_IMPO =


(see key word THER_IMPO),




)


if
MECA_IMPO
then [*]
MECA
if
THER_IMPO
THER

Handbook of Utilization
U4.4- booklet: Modeling
HT-62/06/004/A

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Titrate:
Operators AFFE_CHAR_CINE and AFFE_CHAR_CINE_F

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:
U4.44.03-H1 Page:
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3 General information

These two commands create concepts of the type CHAR_CINE_ * (_MECA/_THER).

Command AFFE_CHAR_CINE can also create concepts of the type CHAR_CINE_ACOU.

These types are different from the type charges created by commands AFFE_CHAR_MECA [U4.44.01],
AFFE_CHAR_THER [U4.44.02] or AFFE_CHAR_ACOU [U4.44.04]).

The objects created are thus not interchangeable.

The advantage of the loads “kinematics” is that they do not increase the number of unknown factors of
systems to be solved, contrary to the method of dualisation by multipliers of LAGRANGE,
used in the commands producing a concept of the type charges.

On the other hand, the use of these loads comprises the following limitations:

·
one can use them only in the case of relation of the type “ddl imposed” (and not for
linear relations),
·
these loads are not yet allowed in all the total commands. Today
the possible commands are:
-
MECA_STATIQUE,
-
THER_LINEAIRE, THER_NON_LINE or THER_NON_LINE_MO.
·
for a calculation not using the total commands: assembly of a matrix, then
resolution, the sequence of commands to be used is more complicated than with loads
“ordinary” as one can see it in example 2 [§ 5.2].
Handbook of Utilization
U4.4- booklet: Modeling
HT-62/06/004/A

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Titrate:
Operators AFFE_CHAR_CINE and AFFE_CHAR_CINE_F

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4 Operands

4.1
General information on the operands

The operands under the key words factors MECA_IMPO, THER_IMPO and ACOU_IMPO are two
forms:

·
operands specifying the geometrical entities on which are affected them
loadings (key words GROUP_MA, GROUP_NO, NOEUD…). Arguments of these operands
are identical for the two operators.
·
operands specifying the affected values (DX, DY, DZ, etc…). Significance of these
operands is the same one for the two operators. The arguments of these operands are all
real type for operator AFFE_CHAR_CINE and of the function type (or formulates) for
operator AFFE_CHAR_CINE_F.

This is true near with an exception: the key word factor ACOU_IMPO (which does not exist in
order AFFE_CHAR_CINE_F) is always of complex type.

We will thus not distinguish in this document, except mention express of the opposite, both
operators AFFE_CHAR_CINE and AFFE_CHAR_CINE_F.

In a general way, the entities on which values must be affected are defined by
nodes:

·
maybe by the operand TOUT = “OUI” which makes it possible to indicate all the nodes of the grid,
·
maybe by operand GROUP_NO allowing to indicate a list of groups of nodes,
·
maybe by operand NOEUD allowing to indicate a list of nodes.
·
maybe by operands GROUP_MA and MAILLE allowing to indicate all the nodes carried
by the meshs indicated by the lists of MAILLE and GROUP_MA.

4.2
Behavior in the event of overload:

4.2.1 Overload within only one command AFFE_CHAR_CINE

When one uses within the same command, several occurrences of MECA_IMPO (or
THER_IMPO,…) and that certain nodes are affected several times, it is the last occurrence which
precede. For example:

chcine= AFFE_CHAR_CINE (MECA_IMPO= (
_F (TOUT=' OUI', DX= 1.,…)
_F (NOEUD=' N3', DX= 3.,…)

In this case, displacement imposed DX for the N3 node is worth: 3.

4.2.2 Overload between several commands AFFE_CHAR_CINE

If several different commands are used, the behavior is different. For example:

CHCIN1= AFFE_CHAR_CINE (MECA_IMPO= _F (TOUT=' OUI', DX= 1.,…)
CHCIN1= AFFE_CHAR_CINE (MECA_IMPO= _F (NOEUD=' N3', DX= 3.,…)

In this case, displacement imposed DX for the N3 node is worth: 4! (1+3).

4.2.3 Overload
enter
AFFE_CHAR_CINE and AFFE_CHAR_MECA

In the same way, if one “mixes” commands AFFE_CHAR_MECA and AFFE_CHAR_CINE:

CHCIN1= AFFE_CHAR_CINE (MECA_IMPO= _F (TOUT=' OUI', DX= 1.,…)
CHDUA1= AFFE_CHAR_MECA (DDL_IMPO= _F (NOEUD=' N3', DX= 3.,…)

In this case, displacement imposed DX for the N3 node is worth: 4! (1+3).
Handbook of Utilization
U4.4- booklet: Modeling
HT-62/06/004/A

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Titrate:
Operators AFFE_CHAR_CINE and AFFE_CHAR_CINE_F

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4.3 Operand
MODELE

MODELE = Mo

Concept produced by operator AFFE_MODELE [U4.41.01] where the types of elements are defined
stop affected on the grid.

4.4 Word
key
MECA_IMPO

4.4.1 Drank

Key word factor usable to impose, with nodes or groups of nodes, a value of
displacement, definite component by component in the total reference mark.

These boundary conditions will be treated, thereafter, by the method known as of elimination of the degrees of
freedom imposed (i.e. without dualisation, contrary on the processing of the same type of condition
limit by the use of operators AFFE_CHAR_MECA or AFFE_CHAR_MECA_F [U4.44.01]).

4.4.2 Syntax

AFFE_CHAR_CINE

/MECA_IMPO = (_F (
/
TOUT
=
“OUI”
,
/
|
NOEUD
=
lno
,
[l_noeud]
|
GROUP_NO
=
lgno,
[l_gr_noeud]


|
MAILLE
= lma
,
[l_maille]


|
GROUP_MA
=
lgma,
[l_gr_maille]








| DX
= ux
,
[R]









| DY
= uy
,
[R]









|
… (see the list supplements below)
),),

AFFE_CHAR_CINE_F

/MECA_IMPO
= (_F
(
/
TOUT
=
“OUI”
,
/
|
NOEUD
=
lno
,
[l_noeud]
|
GROUP_NO
=
lgno,
[l_gr_noeud]
| MAILLE =
lma,
[l_maille]


|
GROUP_MA
=
lgma,
[l_gr_maille]








| DX
= uxf
,


[function (*)]









| DY
= uyf
,
[function (*)]









|
… (see the list supplements below)

),),

function (*): function or formula


List key words available under MECA_IMPO:

DCX DCY DCZ DRX DRY DRZ DX DY DZ E1X E1Y E1Z E2X E2Y E2Z E3X E3Y E3Z E4X
E4Y E4Z GONF GRX H1X H1Y H1Z PHI PRE1 PRE2 CLOSE TEMP UI2 UI3 UI4 UI5 UI6
UO2 UO3 UO4 UO5 UO6 VI2 VI3 VI4 VI5 VI6 VO2 VO3 VO4 VO5 VO6 WI1 WI2 WI3
WI4 WI5 WI6 WO WO1 WO2 WO3 WO4 WO5 WO6

They are the names of the degrees of freedom carried by the finite elements of the model. Significance of these
names is to be sought in the documentation of the finite elements.
Handbook of Utilization
U4.4- booklet: Modeling
HT-62/06/004/A

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Titrate:
Operators AFFE_CHAR_CINE and AFFE_CHAR_CINE_F

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4.4.3 Operands


/MECA_IMPO

DX = ux or uxf
Value of the component of displacement
DY = uy or uyf
in imposed translation
DZ = uz or uzf
on the specified nodes

Only for the nodes of a model 3D comprising of the elements of beam, plates, hull,
discrete:

DRX = X or xf
Value of the component of displacement
DRY = y or yf
in imposed rotation
on the specified nodes
DRZ = y or zf

For the “exotic” degrees of freedom more: GRX, TEMP, PRES and PHI, one will refer to
documentation of command AFFE_CHAR_MECA [U4.44.01 §3.9].

Caution:

It is checked that the degree of freedom specified exists in this node for at least one of the elements
model (key word MODELE) which is based on this node.

Moreover, the rule of overload is applied when the same degree of freedom of same
node is imposed several times: only the last value is retained.

4.5 Word
key
THER_IMPO

4.5.1 Drank

Key word factor usable to impose, with nodes or groups of nodes, a value of
nodal temperature.

These boundary conditions will be treated, thereafter, by the method known as of elimination of the degrees of
freedom imposed (i.e.: without dualisation contrary to the processing of the same type of condition
limit by the use of operators AFFE_CHAR_THER or AFFE_CHAR_THER_F [U4.44.02])

4.5.2 Syntax

·
for AFFE_CHAR_CINE


/THER_IMPO = (_F (
/
TOUT
=
“OUI”
,
/
|
NOEUD
=
lno
,
[l_noeud]
|
GROUP_NO
=
lgno,
[l_gr_noeud]


|
MAILLE
= lma
,
[l_maille]


|
GROUP_MA
=
lgma,
[l_gr_maille]








| TEMP =
T
,

[R]









| TEMP_SUP
= tsup,
[R]









| TEMP_INF
= tinf,
[R]






),),

·
for AFFE_CHAR_CINE_F


/THER_IMPO = (_F (
/
TOUT
=
“OUI”
,
/
|
NOEUD
=
lno
,
[l_noeud]
|
GROUP_NO
=
lgno,
[l_gr_noeud]


|
MAILLE
= lma
,
[l_maille]


|
GROUP_MA
=
lgma,
[l_gr_maille]








| TEMP =
ft
,

[function (*)]









|
TEMP_SUP
= ftsup
,
[function (*)]









| TEMP_INF
= ftinf
,
[function (*)]






),),

function (*): function or formula
Handbook of Utilization
U4.4- booklet: Modeling
HT-62/06/004/A

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Titrate:
Operators AFFE_CHAR_CINE and AFFE_CHAR_CINE_F

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4.5.3 Operands

|
TEMP

Temperature imposed on the nodes (or on the average layer for the thermal hulls)

|
TEMP_INF

Temperature imposed on the lower face for the thermal elements of hulls.

|
TEMP_SUP

Temperature imposed on the higher face for the thermal elements of hulls.

For the hulls, the faces lower and higher are defined, mesh by mesh, the direction
normal external deduced from classification of the nodes: to see FACE_IMPO of
AFFE_CHAR_MECA [U4.44.01].

4.6 Word
key
ACOU_IMPO

4.6.1 Drank

Key word factor usable to impose, with nodes or groups of nodes, a value of
acoustic pressure.

These boundary conditions will be treated, thereafter, by the method known as of elimination of the degrees of
freedom imposed (i.e.: without dualisation contrary to the processing of the same type of condition
limit by the use of operator AFFE_CHAR_ACOU [U4.44.04]).

4.6.2 Syntax

·
For AFFE_CHAR_CINE


/ACOU_IMPO = (_F (
/
TOUT
=
“OUI”
,
/
|
NOEUD
=
lno
,
[l_noeud]
|
GROUP_NO
=
lgno,
[l_gr_noeud]


|
MAILLE
= lma
,
[l_maille]


|
GROUP_MA
=
lgma,
[l_gr_maille]









PRES
=
p
,
[C]






),),

·
For AFFE_CHAR_CINE_F

No key word ACOU_IMPO because it does not have yet a complex function there.

4.6.3 Operands

PRES

Value of the acoustic pressure complexes imposed on (S) the node (S) specified (S).
Handbook of Utilization
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5 Examples

5.1
Degrees of freedom imposed in mechanics

chcine = AFFE_CHAR_CINE
(MODELE = Mo,
MECA_IMPO= (_F
(ALL = “YES”
, DRZ = 0.),







_F (GROUP_NO = “BORD1”, DX = 0., DY = 0., DZ =
0.,
DRX
=
0.,
DRY = 0.,)))

For this problem of plate in plan XY, one blocks all the degrees of freedom of rotation around
of Z and one embeds the plate on his edge bord1.

5.2
Compared use of the loads kinematics and “ordinary”

5.2.1 Commands
total

ch1
= AFFE_CHAR_THER
(…)
ch2 =
AFFE_CHAR_CINE_F
(TEMP_IMPO =
_F (…))
evoth = THER_LINEAIRE
(

EXCIT
=
(
_F
(CHARGE
=
ch1),
_F
(CHARGE
=
ch2),)
…)

There is no difference.

5.2.2 Calculation “step by step”

Ordinary loads

ch1

= AFFE_CHAR_MECA (…)
mel

= CALC_MATR_ELEM (… OPTION = “RIGI_MECA”, LOAD = CH1)

subdued = ASSE_MATRICE (
MATR_ELEM = mel…)

subdued = FACT_LDLT (reuse = subdued, MATR_ASSE = subdued)

U
= RESO_LDLT (MATR_FACT = subdued, CHAM_NO = F)

Loads kinematics

ch1

= AFFE_CHAR_CINE (…)
mel

= CALC_MATR_ELEM (… OPTION = “RIGI_MECA”)

subdued = ASSE_MATRICE (
MATR_ELEM = mel,…, CHAR_CINE = ch1)

subdued = FACT_LDLT (reuse = subdued, MATR_ASSE = subdued,)

vcine = CALC_CHAR_CINE (…, CHAR_CINE = ch2,)

U
= RESO_LDLT (MATR_FACT = subdued, CHAM_NO = F,
CHAM_CINE
=
vcine)

The terms induced by the loads kinematics are deferred to the second member what requires it
calculation of an additional field to the nodes vcine by command CALC_CHAR_CINE [U4.61.03].

Handbook of Utilization
U4.4- booklet: Modeling
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