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

Organization (S): EDF-R & D/AMA, DeltaCAD
Handbook of Utilization
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 modelings thermo elastoplastic 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 model 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]).
Handbook of Utilization
U3.12 booklet: Mechanical elements of structure 2D
HT-66/05/004/A

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

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 model 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 grid. The definition of these data is carried out with
order AFFE_CARA_ELEM associated with the key word following factor:

· COQUE

Allows to define and affect on the meshs, the thickness, the coefficient of shearing,
offsetting,…

Handbook of Utilization
U3.12 booklet: Mechanical elements of structure 2D
HT-66/05/004/A

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

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 disk speed and the vector of rotation.
Supported modelings: COQUE_C_PLAN, COQUE_D_PLAN, COQUE_AXIS

· “PESANTEUR”
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 constraints
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 the linearized deformations key word “PETIT” under DEFORMATION are available in
relations of behavior (Cf. [U4.51.11]).

Handbook of Utilization
U3.12 booklet: Mechanical elements of structure 2D
HT-66/05/004/A

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

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 inflection.
­ 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.

Handbook of Utilization
U3.12 booklet: Mechanical elements of structure 2D
HT-66/05/004/A

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