FORMA01 - Work practice basic training with lutilisation of Code

Code_Aster

Version

6.4

Titrate:

FORMA01 - TP of the basic training to the use of Code_Aster

Date:

16/05/03

Author (S):

J.M. PROIX, I. BAKER, E. BOYERE

Key:

V7.15.100-B

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Manual of Validation V7.15 Booklet: Thermomechanical linear statics of the voluminal systems (formation)

HT-66/03/008/A

Organization (S):

EDF-R & D/AMA

Manual of Validation
V7.15 booklet: Thermomechanical linear statics of the voluminal systems
(formation)
V7.15.100 document

FORMA01 - Work practice formation of
base with the use of Code_Aster

Summary:

This test corresponds to practical work of the basic training to the use of Code_Aster. It is about one
bent piping, made up of a linear elastic material, subjected to various loadings: force applied
with the end, internal pressure, thermal transient.

Modelings used are as follows:

modeling a: beams (

POU_D_T

), which corresponds to the TP1,

modeling b: hulls

DKT

, mesh GIBI,

modeling F: hulls

DKT

, mesh GMSH, identical (with the mesh near) to modeling B,

modeling C: solid elements

, mesh GIBI,

modeling D: beams (

POU_D_T

), dynamic calculation,

modeling E: elements

PIPE

Modeling G: solid elements

, (linear mesh GMSH),

Modeling H: solid elements

, (quadratic mesh GMSH).

The chapter 1 “Problem of reference” presents the problem to be treated and the data common to
all modelings; the statements of Practical Work of the formation are included in it
document:

TP1: “beams” to see modeling A,

TP2: “hulls” to see modeling F,

TP3: “elastic thermo 3D” to see modeling H,

TP4: “dynamic” to see modeling D.

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Problem of reference

1.1 Geometry

The study relates to a piping including/understanding two right pipes and an elbow [Figure 1.1-a].

The geometrical data of the problem are as follows:

the length L

the two right pipes is 3 m,

the Rc radius of the elbow is 0.6 m,

the angle

elbow is 90 degrees,

the thickness of the right pipes and the elbow is 0.02 m,

and the radius external Re of the right pipes and the elbow is of 0.2 Mr.

section B

section D

section C

section A

With

Appear 1.1-a

Note:

The geometry of the problem has a symmetry compared to the plan (A, X, Y).

1.2

Material properties

For all modelings:

Isotropic linear elastic material. the properties of material are those of A42 steel:

the Young modulus E = 204.000. 10

NR/m

the Poisson's ratio

= 0.3,

For elastic thermo calculation (modelings C, G H)
-

the thermal expansion factor

=10.92 10

/°C,

thermal conduction

= 54.6 W/m °C,

voluminal heat

CP = 3.71 10

J/m

°C,

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For dynamic calculation (modeling D)
-

The Young modulus is worth 210.000. 10

NR/m

density

= 7800 kg/m

- the damping of the clean modes will be taken to 2% for the first 2 modes, 3% for

3rd, 4% for the fourth and 5% for the fifth.

1.3

Boundary conditions and loadings

The boundary conditions for all modelings are as follows:

for the mechanical loadings, there is an embedding on the level of section A,

for the thermomechanical loading, there is embedding on the level of section A and of
section B.

With regard to static calculations (modeling A, B, C, E, F, G, H), the loadings applied
are of three types:

force constant FY = 100.000. NR directed according to the axis Y and applied to the section B,

pressure interns P = 15. E+6 NR/m

, (modelings B, C, E, F, G, H)

thermomechanical loading with a transient of temperature imposed on the face
intern of piping (gone up 20°C with 70°C in 10 seconds) and a condition of exchange
no one on the external face of piping (heat insulator) (modeling C only).

With regard to dynamic calculation (modeling D), the loading applied is a force
transient (in Newton):

FY (T) = 1 00.000. * cos (2 *

* Freq1 * T)

directed according to the axis Y and applied to the section B,

Freq1 such as

= 2 *

* Freq1 = 121 rad/S.

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Reference solution

2.1

Method of calculation used for the reference solution

The reference solution is obtained numerically, it thus acts only of the tests of not
regression. However below the results of various modelings are compared.

2.2

Results of various modelings:

2.2.1 Static calculation, Force FY

For the loading of force constant FY applied to the section B, one compares displacement

with

not B for various modelings (or at the point of co-ordinates (Lg+Rc, Lg+Rc, Re) for
modelings hull and 3D):

Loading forces constant FY

Modeling DX

DRZ

A1: beam flexibility = 1

 2.657E02 6.702E

2.097E02

A2: beam flexibility RCCM

 2.983E02 1.156E

3.530E02

B: Hull (mesh GIBI, 1260 QUAD4) 2.90E02

1.06E01

3.27E02

F: Hull (mesh GMSH, 2240 TRIA3, 700 QUAD4)

 2.89E02

1.053E
01

3.24E02

C: 3D (mesh GIBI, 800 HEXA20)

 2.914E02 1.065E

G: 3D (mesh GMSH, 7260 TETRA4, 1240 PENTA6)

 2.65E02

0.731E
01

H: 3D (mesh GMSH, 7260 TETRA10, 1240 PENTA15) 2.94E02

1.056E
01

E: pipe

 2.935E02 1.083E

3.326E02

Maximum relative variation (without taking account of A1 nor G)

For the loading of pressure, one compares displacement with the point B for the different ones
modelings:

Loading

pressure

Modeling DX

DRZ

B: Hull (mesh GIBI, 1260 QUAD4) 2.903E01 4.687E01

1.305E01

F: Hull (mesh GMSH, 2240 TRIA3, 700 QUAD4)

 2.890E01 4.654E01 1.296E01

C: 3D (mesh GIBI, 800 HEXA20)

 2.766E01 4.473E01

G: 3D (mesh GMSH, 7260 TETRA4, 1240 PENTA6)

 2.622E01 3.967E01

H: 3D (mesh GMSH, 7260 TETRA10, 1240 PENTA15)

 2.734E01

4.41E01

E: pipe

 2.763E01 4.505E01 1.257E01

Maximum relative variation

17%

Note:

So that the results of modeling beam are comparable with the different one

modelings, it is necessary to take into account the coefficients of flexibility of the elbows

(

AFFE_CARA_ELEM

flex

with

moy

courb

(value recommended by the RCCM, current regulation).

Code_Aster

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With regard to dynamics, one tests the stresses obtained after restitution in base
physique of transitory calculation by modal recombination (on the basis of clean mode the first 5)
piping subjected to force FY (T), the moment 0.2s, point b:

Component SIXX

SIYY

Stresses at the point B, urgent 0.2s

 5.29775E+05

9.40503E+05

2.3

Uncertainty on the solution

The difference between the various solutions lies between 3% and 17%. This is due on the one hand to
modelings themselves (corrective terms for flexibility in the beams, and coefficient on
pressure in the hulls), and in addition with the mesh used, which is not very fine (so that it
time of resolution is not an embarrassment for the TP of the formation.

Note:

The results 3D are much more precise with a quadratic mesh.

For modeling hull, the pressure is applied to the average surface of radius R

moy

One thus took into account a corrective factor on the value of the pressure to be applied:

P * =P.R

int

moy

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3 Modeling

With

3.1

Characteristics of modeling

3.1.1 Mesh

GMSH

The telegraphic mesh could be built inter-actively using GMSH (or GIBI). It is enough to define
the points A, B, C D, then the two lines AC and dB, item 0 and rings it BC. Size of the elements
could be defined like parameter. In GMSH, one will be able to declare “physical” the points A and B,
then lines AC and data base, then circle BC. Once mesh carried out, to save it (format msh).

The elbow will be modelized initially by at least four elements of right beams
(to provide for GMSH a density lower than 0.25).

With regard to the right pipes, the discretization does not have an influence on the result, because them
elements of right beam of Timoshenko (

POU_D_T

) of Code_Aster provide results

correct with the nodes of the mesh, even for a discretization with very little element, in
LINEAR STATICS only [R3.08.01].

3.2

To drive controls Aster

Reading of the mesh (

PRE_GMSH

) and generation of the mesh (

LIRE_MAILLAGE

Definition of the finite elements used (

AFFE_MODELE

). One will affect initially to

group meshs composing the elbow, as on the right parts, modeling

POU_D_T

Definition and assignment of material (

DEFI_MATERIAU

and

AFFE_MATERIAU

The mechanical characteristics are identical on all the structure.

Assignment of the characteristics of the elements beams (

AFFE_CARA_ELEM

The section of all the pipes is circular.

Definition of the boundary conditions and the loading (

AFFE_CHAR_MECA

Piping is embedded in its base, on the level of point A.

The loading is a specific force FY applied to the point B.

Resolution of the elastic problem (

MECA_STATIQUE

Calculation of the field of efforts generalized by element with the nodes, the field of
displacement calculated (option '

EFGE_ELNO_DEPL

').

Impression of the results (

IMPR_RESU

One will print in form listing displacement at the point B and the maximum values of
efforts.

One will also print the field of displacement to the format

GMSH

, for one

visualization of the results with GMSH. (to use

DEFUFI

to define the output file).

Optional calculation: curved beams and coefficient of flexibility

One will be able to check the impact of a coefficient of flexibility of the elbow on displacements with

not B. This coefficient of flexibility is defined in the level of the control

AFFE_CARA_ELEM

(key word

DEFI_ARC

It will then be necessary to assign to the group of meshs composing the elbow modeling

POU_C_T

Code_Aster

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HT-66/03/008/A

Results of modeling A

4.1 Values

tested

The results obtained with 2 elements in each right part and 4 elements in the elbow are:

Without coefficient of flexibility:

Loading Value

tested

Reference

Aster %

difference

Force concentrated Fy out of B Displacement out of B Dx

 2.657E02 2.657E02

Displacement out of B Dy

6.702E02 6.702E02

Rotation out of B DRZ

2.097E02 2.097E02

With coefficient of flexibility:

Loading Value

tested

Reference

Aster %

difference

Force concentrated Fy out of B Displacement out of B Dx

 2.983E02 2.983E02

Displacement out of B Dy

1.156E01 1.156E01

Rotation out of B DRZ

3.530E02 3.530E02

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5 Modeling

5.1

Characteristics of modeling

In the case of modeling in elements hulls, the mesh consists of the discretization of
surface average piping. Geometry being symmetrical compared to the plan (A, X, Y), one
net that a half-surface.

5.2

Characteristics of the mesh

The mesh is created using GIBI. It comprises 1260 meshs QUAD4, and 1356 nodes

5.3 Controls

Aster

The main stages of calculation with Aster will be:

Reading of the mesh (

PRE_GIBI

) and generation of the mesh (

LIRE_MAILLAGE

Definition of the finite elements used (

AFFE_MODELE

). The right pipes and the elbow will be

modelized by elements of hull (

DKT

Reorientations of the normals to the elements: one will use

MODI_MAILLAGE

to direct all

elements in the same way, with a normal turned towards the interior of the pipe (being
data the convention of sign on the pressure) in order to give a positive value to
pressure.

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Definition and assignment of material (

DEFI_MATERIAU

and

AFFE_MATERIAU

mechanical characteristics are identical on all the structure.

Assignment of the characteristics of the elements hulls (

AFFE_CARA_ELEM

): thickness

Definition of the boundary conditions and the loadings (

AFFE_CHAR_MECA

Piping is embedded in its base, on all the nodes located in the Y=0 plan.
piping presents a symmetry plane Z=0.

One calculates two loading cases:

- an effort distributed F * directed according to the axis Y and applied to the section B, (the effort distributed is such

that the resultant 2Pi * Rmoy F * = FY, FY being the total force which one wishes to apply).
To apply the effort to the section B, one will use

FORCE_ARETE

a pressure interns P.

Note:

The value of the pressure P is positive according to the contrary direction of the normal with

the element. To direct this normal it is necessary to use

MODI_MAILLAGE

ORIEN_NORM_COQUE

: to define in A1 a vector giving the direction of the normal

(opposed to the pressure).

Resolution of the elastic problem for each loading case (2 calls to

MECA_STATIQUE

Impression of the results (

IMPR_RESU

One will print in form listing displacement for each result on the section B. One
will also print with format GMSH, displacements.

One will be able in the second Aster calculation to evaluate the stresses with the nodes:

One adds in the characteristics hulls (

AFFE_CARA_ELEM

) the vector V defining it

identify examination (key word

ANGL_REP

). One can take for example V=Oz.

Calculation of the stress field by elements to the nodes for each loading case (option
'

SIGM_ELNO_DEPL

'). The stresses are calculated in the definite local reference mark for each

element using the vector V (key word

ANG_REP

precedent). To use

NIVE_COUCHE

for

to define the level of calculation in the thickness.

Results of modeling B

6.1 Values

tested

Loading Value

tested

Reference

Aster %

difference

Force concentrated Fy out of B Displacement out of B Dx

 2.901E02 2.901E02

Displacement out of B Dy

1.060E01 1.060E01

Rotation out of B DRZ

3.274E02 3.274E02

Internal pressure

Displacement out of B Dx

 2.903E01 2.903E01

Displacement out of B Dy

4.687E-01 4.687E-01

Rotation out of B DRZ

1.305E-01 1.305E-01

Code_Aster

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7 Modeling

7.1

Characteristics of modeling

The right pipes and the elbow are modelized by isoparametric solid elements
quadratic. Piping presents a symmetry plane Z=0. Only one half volume is netted.

With

Code_Aster

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7.2

Characteristics of the mesh

4240 meshs HEXA20, 5913 nodes

7.3 Controls

Aster

In the case of load thermal, the study requires the first transitory thermal calculation followed of one
mechanical calculation.

In order to use the possibilities of recovery of a calculation, one will make two successive and coupled executions
with Aster. In the first execution, one will make the resolution of the various loading cases, in
second of postprocessings on the thermomechanical loading case.

The main stages of the first execution with Aster will be:

Reading of the mesh (

PRE_GIBI

) and generation of the mesh (

LIRE_MAILLAGE

) in elements

quadratic.

Definition of the finite elements used (

AFFE_MODELE

). One will define a model for calculation

thermics and a mechanical model.

Definition and assignment of material (

DEFI_MATERIAU

and

AFFE_MATERIAU

thermal characteristics and mechanics are identical on all the structure.

Definition of the boundary conditions thermal (

DEFI_FONCTION

and

AFFE_CHAR_THER_F

There is a transient of temperature imposed on the interior surface of piping (installed
of 20°C with 70°C in 10s). It is considered that piping is insulated and thus one applies
a condition of null exchange on external surface.

Resolution of the thermal problem (

THER_LINEAIRE

). The calculation of the field of temperature

be carried out for the two moments of the transient (5. and 10. S).

Definition of the three mechanical loading cases: boundary conditions and loading
mechanics or thermics (

AFFE_CHAR_MECA

- an effort FY directed according to the axis Y and applied to the section B, (to use

FORCE_FACE

value of the surface effort of Fy resultant can be calculated in Aster using

DEFI_VALEUR

an internal pressure,

the thermal transient previously calculated,

- piping is embedded in its base (Ae1, Ai1, Ae2, Ai2), on all the nodes located

in the plan of Y=0 equation. In the case of load thermal, the section B of
piping is also embedded.

Resolution for the various loading cases from the mechanical problem and calculation of the field of
stresses with the nodes by element (3 calls to

MECA_STATIQUE

)

Using

CALC_ELEM

, calculation of the stresses by elements extrapolated with the nodes

(

SIEF_ELNO_ELGA

) and of the equivalent stresses of Von Mises (

EQUI_ELNO_SIGM

Impression of the results (

IMPR_RESU

- One will print in form listing on the one hand displacement on the section B, and of other

leaves the maximum values the tensor of stresses, in the case of load
mechanics.

- One will print for thermomechanical calculation, displacements, and the component

VMIS

on field

EQUI_ELNO_SIGM

with the format

CASTEM

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The main stages of the second execution with Aster will be:

Creation of a table per extraction of values on a path (

INTE_MAIL_3D

and

POST_RELEVE_T

One will extract from the values of temperature and displacement for an azimuth on the level from
the input of elbow in the case of load thermomechanical. The azimuth is defined by the path
ends (0. 3. 0.1) and (0. 3. 0.2).

Impression of curves (

IMPR_COURBE

One will print with format AGRAF the change of the temperature and the component following Y
field of displacement, along the preceding azimuth. One will be able to then visualize these
curves by means of AGRAF.

Results of modeling C

8.1 Values

tested

Loading Value

tested

Reference

Aster %

difference

Force concentrated Fy out of B

Displacement out of B Dx

 2.907E02 2.907E02 0

Displacement out of B Dy

1.065E01 1.065E01 0

Internal pressure

Displacement out of B Dx

 2.763E01 2.763E01 0

Displacement out of B Dy

4.472E01 4.472E01 0

Temperature at the moment 10s Temperature in AI1

70 70 0

Stress of Von
Settings maximum

1.2383 10

1.2383

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9 Modeling

9.1

Characteristics of modeling

The geometry is identical to that of modeling A. the mesh must be enough fine to obtain
a correct solution in dynamics, in particular to describe the clean modes correctly:
bend and the right pipes will be modelized chacuns by at least 5 elements of right beams of
Timoshenko

POU_D_T

One first of all wishes to know the first clean modes.

Then one will make a transitory analysis of the response of the pipe to the sinusoidal force between 0.0 and 2.0 S.
The structure is initially at rest. One will be able initially to make the analysis on basis
modal. One will be able to compare the results of the analysis on modal basis with a direct analysis on
base physical.

9.2

Characteristics of the mesh

9.2.1 Mesh

GMSH

The mesh will be obtained with GMSH, as for modeling A. Attention not being forgotten in
the command file ASTER to create the groups of “physical” meshs and, then, in
command file ASTER to create the groups of nodes corresponding to the groups of meshs
thanks to the control

DEFI_GROUP

9.2.2 Alternative mesh: with GIBI

For those which prefer GIBI, one will be able to create the mesh using this maillor, in the following way:
one will create with the editor a data file which will include/understand the list of the instructions that one will subject
with GIBI. The various stages of modeling with GIBI will be:

Definition of the options of mesh by the procedure

OPTION

The co-ordinates of the points will be introduced in dimension 3.

The elements will be of type

SEG2.

Definition of the points A, B, C, D, O.
The points will be named AP, PB, PC, PD, PO.

Mesh of piping
For the mesh of piping, one will use the operators

STRAIGHT LINE

RING

and

AND

Cutting will be of only one element for the right pipes and the elbow.

Visualization of the final mesh.
Visualization is done by the procedure

TO TRACE

, for which one must specify a point, which

indicate the position of the eye which looks at the object.

Back up mesh for its use in Aster.
To be able to read again the mesh by Aster it should be backed up in a formatted file, this
back up is done by the procedure

TO SAVE

with the key word

FORMAT

. The file which will be creates

the same name will have as the data file GIBI, but will have as an extension “.mgib”.

Stop of the execution of GIBI.
To leave GIBI it should be indicated by the directive

END

Note:

Any instruction GIBI ends in the symbol “;”.

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9.3 Controls

Aster

The main stages of calculation with Aster will be:

9.3.1 Preparation of the data and analyzes modal

Mesh (not to forget it

PRE_GMSH

or it

PRE_GIBI

Definition of the finite elements used (

AFFE_MODELE

One will use the groups of meshs envisaged in GMSH (or GIBI).

Definition and assignment of material (

DEFI_MATERIAU

and

AFFE_MATERIAU

The mechanical characteristics are identical on all the structure.

Assignment of the characteristics of the elements beams (

AFFE_CARA_ELEM

The section of all the pipes is circular, of radius 0.2 m and thickness
0.02 Mr.

The elbow constitutes of an arc of circle of center the point O and radius 0.6 Mr. to define
the curved element, one will use the key word

DEFI_ARC

Definition of the boundary conditions and the loading (

AFFE_CHAR_MECA

). Point A is

embedded.

Definition of the matrices of the elastic problem (

MACRO_MATR_ASSE

Calculation of the first 5 clean modes (

MODE_ITER_SIMULT

Impression of the clean modes (

IMPR_RESU

): one will print the mesh and the modes with the format

GMSH for a visualization in GMSH (or with format CASTEM, for a visualization of
results with GIBI). In the case of GMSH, not to forget to open the logical unit of the file of
postprocessing by one

DEFUFI

9.3.2 Analyze

transient

Construction of the specific force

Definition of the load forces at the point B (

AFFE_CHAR_MECA FORCE_NODALE

Calculation of the elementary vectors forces (

CALC_VECT_ELEM

Assembly of the vector forces (

ASSE_VECTEUR

Definition of the function evolution of time (

FORMULATE

Transient on modal basis

Projection of the problem assembled on the basis of clean mode (

MACRO_PROJ_BASE

Transitory calculation by modal recombination (

DYNA_TRAN_MODAL

Recovery of displacements, speed in there of B, C, D (

RECU_FONCTION

Impression of these functions to the format listing and AGRAF (

IMPR_COURBE

One will be able to possibly determine the stresses MIN and MAX due to the efforts
generalized during the transient while passing by a restitution on the physical basis
(

REST_BASE_PHYS

), a calculation of the stresses (

CALC_ELEM

), a skilful postprocessing for

to calculate the maximum in the course of time (

CREA_CHAMP

) and a writing in the file result

(

IMPR_RESU

Code_Aster

Version

6.4

Titrate:

FORMA01 - TP of the basic training to the use of Code_Aster

Date:

16/05/03

Author (S):

J.M. PROIX, I. BAKER, E. BOYERE

Key:

V7.15.100-B

Page:

15/28

Manual of Validation V7.15 Booklet: Thermomechanical linear statics of the voluminal systems (formation)

HT-66/03/008/A

Direct calculation on physical basis: transient on physical basis

Direct transitory calculation by Newmark (

DYNA_LINE_TRAN

Recovery of displacements, speed in there of B, C, D (

RECU_FONCTION

Impression of these functions to the format listing and AGRAF (

IMPR_COURBE

Calculation of the MAX (space and temporal) of the stresses due to the generalized efforts.

9.3.3 Postprocessings

One will visualize with GMSH or GIBI the mesh and the first five clean modes of the structure.
One will also trace using AGRAF the evolution of displacements according to time at the points
B, C and D.
Lastly, one will be able to determine the maximum (and minimum) space and temporal of the stresses due to
generalized efforts, in order to consider the stresses maximum which the pipe during this test undergoes.

9.3.3.1 Help for postprocessing with GMSH

Postprocessing in GMSH is rather intuitive. However some points are to be known:

One must put GMSH in Post-Processing mode.

In Tools/Options, the Aspect miter makes it possible to specify Displacement like Vector display,
i.e. to observe the modes like a structural deformation. One will be able to also specify
the amplitude of the deformation thanks to the box Vector size.

The Step button of the General miter makes it possible, as for him, to make ravel the various modes
(which is seen in GMSH like “pitches of time”).

9.3.3.2 Help for postprocessing with GIBI (possibly)

One will provide a command file GIBI allowing to carry out graphic postprocessings.
Main controls GIBI used are:

* Second reading of the file result to format “CASTEM” coming from Aster:
OPTI REST FORMAT “nom_de_fichier.cast”;
REST FORMAT;
* Recovery of the number of moments calculated in the object “resu” resulting
of Aster
ninst = DIME resu;
* One can display it:
LIST ninst;
i=0;
* Loop over every filed moment:
to repeat ninst boucl1:
I = i+1;

Ti = resu. I. inst;

* Recovery of the fields of displacements in the result:
C = resu. I. depl;
* visualization of the deformation
defo1 = defo red mall C 100.;
defo0 = defo mall green C 0.;
titrate “deformed Piping urgent” Ti;
trac oe (defo1 and defo0);
end boucl1;

Code_Aster

Version

6.4

Titrate:

FORMA01 - TP of the basic training to the use of Code_Aster

Date:

16/05/03

Author (S):

J.M. PROIX, I. BAKER, E. BOYERE

Key:

V7.15.100-B

Page:

16/28

Manual of Validation V7.15 Booklet: Thermomechanical linear statics of the voluminal systems (formation)

HT-66/03/008/A

9.3.3.3 Help for postprocessing with AGRAF

Visualization of curves of results printed with format AGRAF. In the continuation, one will replace
<résultat> by the name of the file result of the type AGRAF produced by the control

IMPR_COURBE

the command file.

The various stages of the visualization of the results with AGRAF are:

launching of AGRAF: to type “agraf” in a Unix window,

opening of a file Directives: small Directives (cf Table 1),

to select To open, give a name of directive by the BSF (for example <résultat>.digr),
to click in the BSF on Opening Directive, and confirming the creation of a new file of
directives,

reading of the results resulting from Aster: small Data (cf Table 1),

to select the file <résultat>.dogr thanks to the BSF,

definition of the graph to be traced: small Graphs,

to select To specify/a window entitled Spécification of the curves of a graph opens,

a Titer area makes it possible to give a title/titer to the graph, to replace Nouveau graph by
titrate your graph (ex: Displacement of the pipe) - in lower parts, actionable with wish by
a toggle-short prop, appear of the lines of definition of the curves to trace,

area Abscisses one defines the n° table and the n° of the column constituting the data in
to put in X-coordinates of the curve (1 1 for the L era curves),

area Ordonnées one defines No of the table and No of the column constituting the data in
to put in ordinates of the curve (1 2 for the first curve),

area Marqueur one defines the shape of the marker, the interval of layout of this marker (all
N points of the curve), (10),

légende area makes it possible to give a text of legend following the curve curve (DY-B),

to click on Backing up to record the definition of the graph,

Back up and updating of the graph to be traced: small Graphs,
-

button To back up,

button To trace,

Impression POSTSCRIPT of the graph: fenestrate Tracé,

button To print the Layout,

Code_Aster

Version

6.4

Titrate:

FORMA01 - TP of the basic training to the use of Code_Aster

Date:

16/05/03

Author (S):

J.M. PROIX, I. BAKER, E. BOYERE

Key:

V7.15.100-B

Page:

17/28

Manual of Validation V7.15 Booklet: Thermomechanical linear statics of the voluminal systems (formation)

HT-66/03/008/A

10 Results of modeling D

10.1 Values

tested

This test is a test of nonregression. The values of reference are the results obtained with
version 6.4 of Code_Aster.

Loading

Value tested

Reference

Aster %

difference

Force concentrated
Fy out of B

Stress out of B due to the effort
normal SN

 6.20356 10

 6.20356

In addition to this result of nonregression, one can observe displacement according to Y of the point D:

One observes that the modes of the structure are excited during the first second transient, it
who explains the chahutée shape of the curve of displacement. Then movements of the modes
clean are deadened and there remains only the stationary movement regulated on the frequency of
sinusoidal force at the point B.

Code_Aster

Version

6.4

Titrate:

FORMA01 - TP of the basic training to the use of Code_Aster

Date:

16/05/03

Author (S):

J.M. PROIX, I. BAKER, E. BOYERE

Key:

V7.15.100-B

Page:

18/28

Manual of Validation V7.15 Booklet: Thermomechanical linear statics of the voluminal systems (formation)

HT-66/03/008/A

11 Modeling

11.1 Characteristics of modeling

Modeling PIPE. The elbow is modelized by 20 elements of the segment type to 3 nodes.

The right pipes are modelized by 20 elements of the segment type to 3 nodes.

The first two loadings (specific force FY and pressure intern) are treated.

11.2 Characteristics of the mesh

60 meshs SEG3, 126 nodes

11.3 Functionalities

tested

Controls

AFFE_CHAR_MECA FORCE_TUYAU

NEAR

MECA_STATIQUE

CALC_ELEM OPTION

SIGM_ELNO_DEPL

AFFE_CHAR_MECA FORCE_NODALE

12 Results of modeling E

12.1 Values

tested

Loading Value

tested

Reference

Aster %

difference

Force concentrated Fy out of B Displacement out of B Dx

 2.935E02 2.935E02 0

Displacement out of B Dy

1.083E01 1.083E01 0

(Reference pipe)

Rotation out of B DRZ

3.326E02 3.326E02 0

Internal pressure

Displacement out of B Dx

 2.7624E01 2.7624E

Displacement out of B Dy

4.505E01 4.505E01 0

Rotation out of B DRZ

1.257E01 1.257E01 0

Code_Aster

Version

6.4

Titrate:

FORMA01 - TP of the basic training to the use of Code_Aster

Date:

16/05/03

Author (S):

J.M. PROIX, I. BAKER, E. BOYERE

Key:

V7.15.100-B

Page:

20/28

Manual of Validation V7.15 Booklet: Thermomechanical linear statics of the voluminal systems (formation)

HT-66/03/008/A

13.2 Characteristics of the mesh

700 meshs QUAD4, 2240 meshs TRIA3, 1344 nodes

Mesh GMSH built in quadrilaterals and triangles is available in the base of the tests:
geometrical data file names forma01f.datg. (to change the extension into “.geo”). It
the numbers of the entities “physical corresponds to the geometry above (to find” which
correspond to the groups of meshs, to use Tools/Visibility/Physical). The groups correspond
with:

GM30 <=> surface of the PIPE
GM28 <=> section B (effort)
GM31 <=> not A1

(- R, 0, 0)

GM27 <=> section A (embedding)
GM29 <=> SYMMETRY

13.3 Controls

Aster

Reading of the mesh (

PRE_GMSH

) and generation of the mesh (

LIRE_MAILLAGE

). One can

to use

DEFI_GROUP

to re-elect the groups of meshs according to the correspondence:

# GM30 <=> PIPE
# GM28 <=> EFOND
# GM31 <=> A1
# GM27 <=> ENCAST
# GM29 <=> SYMMETRY

Definition of the finite elements used (

AFFE_MODELE

). The right pipes and the elbow will be

modelized by elements of hull (

DKT

Reorientations of the normals to the elements: one will use

MODI_MAILLAGE

to direct all

elements in the same way, with a normal turned towards the interior of the pipe (being
data the convention of sign on the pressure) in order to give a positive value to
pressure.

Definition and assignment of material (

DEFI_MATERIAU

and

AFFE_MATERIAU

mechanical characteristics are identical on all the structure.

Assignment of the characteristics of the elements hulls (

AFFE_CARA_ELEM

): thickness

Definition of the boundary conditions and the loadings (

AFFE_CHAR_MECA

Piping is embedded in its base, on all the nodes located in the Y=0 plan.
piping presents a symmetry plane Z=0.

One calculates two loading cases:

An effort distributed F * directed according to the axis Y and applied to the section B, (the effort distributed is such as
the resultant 2Pi * Rmoy F * = FY, FY being the total force which one wishes to apply). For
to apply the effort to the section B, one will use

FORCE_ARETE

A pressure interns P. Remarque: The value of the pressure p is positive according to the direction
opposite of the normal to the element. To direct this normal it is necessary to use

MODI_MAILLAGE

ORIEN_NORM_COQUE

: to define in A1 a vector giving the direction of

normal (opposed to the pressure).

Code_Aster

Version

6.4

Titrate:

FORMA01 - TP of the basic training to the use of Code_Aster

Date:

16/05/03

Author (S):

J.M. PROIX, I. BAKER, E. BOYERE

Key:

V7.15.100-B

Page:

21/28

Manual of Validation V7.15 Booklet: Thermomechanical linear statics of the voluminal systems (formation)

HT-66/03/008/A

Resolution of the elastic problem for each loading case (2 calls to

MECA_STATIQUE

Impression of the results (

IMPR_RESU

One will print in form listing displacement for each result on the section B. One
will also print with format GMSH, displacements.

One will be able in the second Aster calculation to evaluate the stresses with the nodes:

One adds in the characteristics hulls (

AFFE_CARA_ELEM

) the vector V defining it

identify examination (key word

ANGL_REP

). One can take for example V=Oz.

Calculation of the stress field by elements to the nodes for each loading case (option
'

SIGM_ELNO_DEPL

'). The stresses are calculated in the definite local reference mark for each

element using the vector V (key word

ANG_REP

precedent). To use

NIVE_COUCHE

for

to define the level of calculation in the thickness.

14 Results of modeling F

14.1 Values

tested

Loading Value

tested

Reference

Aster %

difference

Force concentrated Fy out of B Displacement out of B Dx

 2.89E02 2.89E02

Displacement out of B Dy

1.053E01 1.053E01

Rotation out of B
DRZ

3.24E02 3.24E02

Internal pressure

Displacement out of B Dx

 2.890E01 2.890E01

Displacement out of B Dy

4.654E01 4.654E01

Rotation out of B
DRZ

1.296E01 1.296E01

Code_Aster

Version

6.4

Titrate:

FORMA01 - TP of the basic training to the use of Code_Aster

Date:

16/05/03

Author (S):

J.M. PROIX, I. BAKER, E. BOYERE

Key:

V7.15.100-B

Page:

23/28

Manual of Validation V7.15 Booklet: Thermomechanical linear statics of the voluminal systems (formation)

HT-66/03/008/A

15.2 Characteristics of the mesh

A number of nodes:

6633

A number of meshs and types: 7260 TETRA4

1539 PENTA6
4319 QUAD4
7003 TRIA3

15.3 Controls

Aster

In the case of load thermal, the study requires the first transitory thermal calculation followed of one
mechanical calculation.

The main stages of the first execution with Aster will be:

Reading of the mesh (

PRE_GMSH

) and generation of the mesh (

LIRE_MAILLAGE

) in elements

linear. One can use

DEFI_GROUP

to re-elect the groups of meshs according to

correspondence:

PIPE <=> GM10000
EFOND <=> GM10005
ENCAST <=> GM10001
SYMMETRY <=> GM10002
SURFINT <=> GM10004
SURFEXT <=> GM10003

Definition of the finite elements used (

AFFE_MODELE

). One will define a model for calculation

thermics and a mechanical model.

Definition and assignment of material (

DEFI_MATERIAU

and

AFFE_MATERIAU

thermal characteristics and mechanics are identical on all the structure.

Definition of the boundary conditions thermal (

DEFI_FONCTION

and

AFFE_CHAR_THER_F

Resolution of the thermal problem (

THER_LINEAIRE

). The calculation of the field of temperature

be carried out for the two moments of the transient (5. and 10. S).

Definition of the three mechanical loading cases: boundary conditions and loading
mechanics or thermics (

AFFE_CHAR_MECA

- an effort FY directed according to the axis Y and applied to the section B, (to use

FORCE_FACE

value of the surface effort of Fy resultant can be calculated in Aster using

DEFI_VALEUR

an internal pressure,

the thermal transient previously calculated,

- piping is embedded in its base (Ae1, Ai1, Ae2, Ai2), on all the nodes located

in the plan of Y=0 equation. In the case of load thermal, the section B of
piping is also embedded.

Code_Aster

Version

6.4

Titrate:

FORMA01 - TP of the basic training to the use of Code_Aster

Date:

16/05/03

Author (S):

J.M. PROIX, I. BAKER, E. BOYERE

Key:

V7.15.100-B

Page:

24/28

Manual of Validation V7.15 Booklet: Thermomechanical linear statics of the voluminal systems (formation)

HT-66/03/008/A

Resolution for the various loading cases from the mechanical problem and calculation of the field of
stresses with the nodes by element (3 calls to

MECA_STATIQUE

)

Using

CALC_ELEM

, calculation of the stresses by elements extrapolated with the nodes

(

SIEF_ELNO_ELGA

) and of the equivalent stresses of Von Mises (

EQUI_ELNO_SIGM

Impression of the results (

IMPR_RESU

- One will print in form listing on the one hand displacement on the section B, and of other

leaves the maximum values the tensor of stresses, in the case of load
mechanics.

- One will print for thermomechanical calculation, displacements, and the component

VMIS

on field

EQUI_ELNO_SIGM

with the format

GMSH

The main stages of the second execution with Aster will be:

Creation of a table per extraction of values on a path (

INTE_MAIL_3D

and

POST_RELEVE_T

Impression of curves (

IMPR_COURBE

16 Results of modeling G

16.1 Values

tested

Loading

Value tested

Reference

Aster %

difference

Force concentrated Fy out of B

Displacement out of B Dx

 2.65E02 2.65E02 0

Displacement out of B Dy

0.731E01 0.731E01

Internal pressure

Displacement out of B Dx

 2.622E01 2.622E01 0

Displacement out of B Dy

3.967E01 3.967E01

Temperature at the moment 10s Temperature in AI1

70 70 0

Code_Aster

Version

6.4

Titrate:

FORMA01 - TP of the basic training to the use of Code_Aster

Date:

16/05/03

Author (S):

J.M. PROIX, I. BAKER, E. BOYERE

Key:

V7.15.100-B

Page:

26/28

Manual of Validation V7.15 Booklet: Thermomechanical linear statics of the voluminal systems (formation)

HT-66/03/008/A

17.2 Characteristics of the mesh

A number of nodes:

5029

A number of meshs and types: 188 HEXA20

658 PENTA15
1136 QUAD8
28 TRIA6

17.3 Functionalities

tested

In the case of load thermal, the study requires the first transitory thermal calculation followed of one
mechanical calculation.

The main stages of the first execution with Aster will be:

Reading of the mesh (

PRE_GMSH

) and generation of the mesh in quadratic elements (word

key

MODI_QUAD

). Call to

LIRE_MAILLAGE

to read this quadratic mesh. One can use

DEFI_GROUP

to re-elect the groups of meshs according to the correspondence:

PIPE <=> GM10000
EFOND <=> GM10005
ENCAST <=> GM10001
SYMMETRY <=> GM10002
SURFINT <=> GM10004
SURFEXT <=> GM10003

Definition of the finite elements used (

AFFE_MODELE

). One will define a model for calculation

thermics and a mechanical model.

Definition and assignment of material (

DEFI_MATERIAU

and

AFFE_MATERIAU

thermal characteristics and mechanics are identical on all the structure.

Definition of the boundary conditions thermal (

DEFI_FONCTION

and

AFFE_CHAR_THER_F

Resolution of the thermal problem (

THER_LINEAIRE

). The calculation of the field of temperature

be carried out for the two moments of the transient (5. and 10. S).

Definition of the three mechanical loading cases: boundary conditions and loading
mechanics or thermics (

AFFE_CHAR_MECA

- an effort FY directed according to the axis Y and applied to the section B, (to use

FORCE_FACE

value of the surface effort of Fy resultant can be calculated in Aster using

DEFI_VALEUR

an internal pressure,

the thermal transient previously calculated,

- Piping is embedded in its base (Ae1, Ai1, Ae2, Ai2), on all the nodes located

in the plan of Y=0 equation. In the case of load thermal, the section B of
piping is also embedded.

Code_Aster

Version

6.4

Titrate:

FORMA01 - TP of the basic training to the use of Code_Aster

Date:

16/05/03

Author (S):

J.M. PROIX, I. BAKER, E. BOYERE

Key:

V7.15.100-B

Page:

27/28

Manual of Validation V7.15 Booklet: Thermomechanical linear statics of the voluminal systems (formation)

HT-66/03/008/A

Resolution for the various loading cases from the mechanical problem and calculation of the field of
stresses with the nodes by element (3 calls to

MECA_STATIQUE

)

Using

CALC_ELEM

, calculation of the stresses by elements extrapolated with the nodes

(

SIEF_ELNO_ELGA

) and of the equivalent stresses of Von Mises (

EQUI_ELNO_SIGM

Impression of the results (

IMPR_RESU

- One will print in form listing on the one hand displacement on the section B, and of other

leaves the maximum values the tensor of stresses, in the case of load
mechanics.

- One will print for thermomechanical calculation, displacements, and the component

VMIS

on field

EQUI_ELNO_SIGM

with the format

GMSH

The main stages of the second execution with Aster will be:

Creation of a table per extraction of values on a path (

INTE_MAIL_3D

and

POST_RELEVE_T

Impression of curves (

IMPR_COURBE

18 Results of modeling H

18.1 Values

tested

Loading

Value tested

Reference (3D

MOD. C)

Aster %

difference

Force concentrated Fy out of B

Displacement out of B Dx

 2.94E02 2.94E02 0

Displacement out of B Dy

1.056E01 1.056E01 0

Internal pressure

Displacement out of B Dx

 2.734E01 2.734E01 0

Displacement out of B Dy

4.41E01 4.410E01

Temperature at the moment 10s Temperature in AI1

70 70 0

Code_Aster

Version

6.4

Titrate:

FORMA01 - TP of the basic training to the use of Code_Aster

Date:

16/05/03

Author (S):

J.M. PROIX, I. BAKER, E. BOYERE

Key:

V7.15.100-B

Page:

28/28

Manual of Validation V7.15 Booklet: Thermomechanical linear statics of the voluminal systems (formation)

HT-66/03/008/A

19 Summary of the results

The purpose of this test is not to validate functionalities, but is used for the formation. However, it
is interesting to compare certain modelings of the same problem. It is noted that the variations
remain relatively weak (5% of variation to the maximum between 3D (quadratic elements), hull and
pipe).