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Code_Aster
®
Version
7.4
Titrate:
Modelings
COQUE_C_PLAN
,
COQUE_D_PLAN
,
COQUE_AXIS
Date:
03/06/05
Author (S):
X. DESROCHES, F. LEBOUVIER
Key
:
U3.12.02-D
Page
:
1/4
Instruction manual
U3.12 booklet: Mechanical elements of structure 2D
HT-66/05/004/A
Organization (S):
EDF-R & D/AMA, DeltaCAD















Instruction manual
U3.12 booklet: Mechanical elements of structure 2D
Document: U3.12.02



Modelings
COQUE_C_PLAN
,
COQUE_D_PLAN
,
COQUE_AXIS

Summary:

This document describes for modelings
COQUE_C_PLAN
,
COQUE_D_PLAN
,
COQUE_AXIS
:
·
degrees of freedom carried by the finite elements which support modeling,
·
the related meshs supports,
·
supported loadings,
·
nonlinear possibilities,
·
case-tests implementing modelings.

Three elastoplastic thermo modelings
COQUE_C_PLAN
,
COQUE_D_PLAN
,
COQUE_AXIS
correspond to a formulation resulting from the models
3D
with a kinematics of hull [R3.07.02].
They are usable to modelize structures on average surface of particular geometry:
·
hulls with symmetry of revolution around axis OY,
·
cylindrical hulls with unspecified section invariant along axis OZ.

Thermomechanical calculations are chained starting from the finite elements of thermal hulls (see [U3.22.01]).
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Code_Aster
®
Version
7.4
Titrate:
Modelings
COQUE_C_PLAN
,
COQUE_D_PLAN
,
COQUE_AXIS
Date:
03/06/05
Author (S):
X. DESROCHES, F. LEBOUVIER
Key
:
U3.12.02-D
Page
:
2/4
Instruction manual
U3.12 booklet: Mechanical elements of structure 2D
HT-66/05/004/A
1 Discretization
1.1
Degrees of freedom
For three modelings of hull the degrees of freedom of discretization are, in each node of
the mesh support, three components of displacement (two translations and a rotation).
nodes are supposed to belong to the average surface of the hull.

Finite element
Degrees of freedom (with each node node)
METCSE3
DX
DY
DRZ
METDSE3
DX
DY
DRZ
MECXSE3
DX
DY
DRZ

1.2
Net support of the matrices of rigidity
The meshs support of the finite elements, in displacement formulation, are segments with three
nodes:
Modeling Nets Element
finished
Remarks
COQUE_C_PLAN
SEG3
METCSE3
COQUE_D_PLAN
SEG3
METDSE3
COQUE_AXIS
SEG3
MECXSE3

1.3
Net support of the loadings
All the applicable loadings on the average surface of the elements of hull are treated by
direct discretization on the mesh support of the element in displacement formulation.
No mesh support of loading is thus necessary for the faces of the elements of hulls.
For imposed displacements the meshs support are meshs reduced to a point.
For modeling
COQUE_C_PLAN
, the width of the hull (in direction Z) is by convention
equalize with the unit. If one must modelize a width different from the unit, it is advisable to take it in
count by modifying for example the loading.

2
Assignment of the characteristics
For these elements of structures 2D, it is necessary to affect geometrical characteristics which
are complementary to the data of mesh. The definition of these data is carried out with
order
AFFE_CARA_ELEM
associated the key word following factor:
·
HULL
Allows to define and affect on the meshs, the thickness, the coefficient of shearing,
offsetting,…
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Code_Aster
®
Version
7.4
Titrate:
Modelings
COQUE_C_PLAN
,
COQUE_D_PLAN
,
COQUE_AXIS
Date:
03/06/05
Author (S):
X. DESROCHES, F. LEBOUVIER
Key
:
U3.12.02-D
Page
:
3/4
Instruction manual
U3.12 booklet: Mechanical elements of structure 2D
HT-66/05/004/A
3 Loadings
supported
The loadings available are as follows:
·
“FORCE_COQUE”
Allows to apply surface efforts.
Supported modelings:
COQUE_C_PLAN
,
COQUE_D_PLAN
,
COQUE_AXIS
·
“PRES_REP”
Allows to apply a pressure to a field of continuous medium.
Supported modelings:
COQUE_C_PLAN
,
COQUE_D_PLAN
,
COQUE_AXIS
·
“TEMP_CALCULEE”
Allows to apply a thermal loading.
Supported modelings:
COQUE_C_PLAN
,
COQUE_D_PLAN
,
COQUE_AXIS
·
“ROTATION”
Allows to define the rotational speed and the vector of rotation.
Supported modelings:
COQUE_C_PLAN
,
COQUE_D_PLAN
,
COQUE_AXIS
·
“GRAVITY”
Allows to apply a loading of the gravity type.
Supported modelings:
COQUE_C_PLAN
,
COQUE_D_PLAN
,
COQUE_AXIS


4 Possibilities
non-linear
4.1
Law of behaviors
Laws of behaviors specific to these modelings, usable under
COMP_INCR
in
STAT_NON_LINE
and
DYNA_NON_LINE
are the relations of behavior in plane stresses
available with modelings
“AXIS”
and
“C_PLAN”
. These relations are to be used with the key word
ALGO_C_PLAN = ' DEBORST'
'(Cf [U4.51.11]).

4.2 Deformations
Only linearized deformations key word
“SMALL”
under
DEFORMATION
are available in
relations of behavior (cf [U4.51.11]).
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Code_Aster
®
Version
7.4
Titrate:
Modelings
COQUE_C_PLAN
,
COQUE_D_PLAN
,
COQUE_AXIS
Date:
03/06/05
Author (S):
X. DESROCHES, F. LEBOUVIER
Key
:
U3.12.02-D
Page
:
4/4
Instruction manual
U3.12 booklet: Mechanical elements of structure 2D
HT-66/05/004/A
5
Examples of implementation: case-tests
·
COQUE_D_PLAN
­ Statique
linear
SSLS114K [V3.03.114]: Quasi-static analysis of a cylindrical quarter of binding ring subjected to
a pressure.
­ Statique
non-linear
SSNV115F [V6.04.115]: Elastoplastic non-linear quasi-static analysis of a sheet
undulated with a law of behavior with criterion of Von Mises with linear work hardening,
subjected has efforts of membrane and bending.
­ Dynamique
linear
SDLS501B [V2.03.501]: Seek Eigen frequencies and modes associated with one
iron corrugated into free-free.
·
COQUE_C_PLAN
­ Statique
linear
SSLS114J [V3.03.114]: Quasi-static analysis of a cylindrical quarter of binding ring subjected to one
pressure.
­ Statique
non-linear
SSNL501A [V6.02.501]: Analyze of a beam, made up of an elastic material
perfectly plastic, embedded at the two ends and subjected to a uniform pressure.
­ Dynamique
linear
SDLL02C [V2.02.002]: Seek frequencies of vibration and modes associated with one
hurled, embed-free beam folded up on itself.
·
COQUE_AXIS
­ Statique
linear
SSLS114I [V3.03.114]: Quasi-static analysis of a cylindrical quarter of binding ring subjected to one
pressure.