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Code_Aster
®
Version
7.3
Titrate:
SSNA113 - Notched sample in viscoplasticity
Date
:
13/10/04
Author (S):
S. MICHEL-PONNELLE, A. PARROT
Key
:
V6.01.113-A
Page:
1/6
Manual of Validation
V6.01 booklet: Nonlinear statics into axisymmetric
HT-66/04/005/A
Organization (S):
EDF-R & D/AMA, MMC















Manual of Validation
V6.01 booklet: Nonlinear statics into axisymmetric
Document: V6.01.113



SSNA113 ­ Notched sample in viscoplasticity




Summary:

This test modelizes a notched sample into axisymmetric. The law of behavior used is the law
VISC_ISOT_TRAC. Two loading rates are simulated:
· slow:
T = 1000s
that is to say
1
3
10
-
-
=
S
&
· rapid:
T = 0.001s
that is to say
1
3
10
-
=
S
&

The results (effort resulting and contraction from the ligament) are compared with the calculations carried out with the model
of viscous Rousselier (ROUSS_VISC) degenerated so that the evolution of porosity is negligible.

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Code_Aster
®
Version
7.3
Titrate:
SSNA113 - Notched sample in viscoplasticity
Date
:
13/10/04
Author (S):
S. MICHEL-PONNELLE, A. PARROT
Key
:
V6.01.113-A
Page:
2/6
Manual of Validation
V6.01 booklet: Nonlinear statics into axisymmetric
HT-66/04/005/A
1
Problem of reference
1.1 Geometry
3
5.4
4.8
30
P0
P1
P2
P8
P9
U
D
3
5.4
4.8
30
P0
P1
P2
P8
P9
U
D

The test-tube is axisymmetric, and only half of the test-tube is represented. Dimensions
are given in millimetres.
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Code_Aster
®
Version
7.3
Titrate:
SSNA113 - Notched sample in viscoplasticity
Date
:
13/10/04
Author (S):
S. MICHEL-PONNELLE, A. PARROT
Key
:
V6.01.113-A
Page:
3/6
Manual of Validation
V6.01 booklet: Nonlinear statics into axisymmetric
HT-66/04/005/A
1.2
Properties of material
Isotropic elasticity
Young modulus:
MPa
215000
=
E
Poisson's ratio:
= 0.3
Traction diagram
Traction diagram
400
500
600
700
800
900
1000
1100
0
0,2
0,4
0,6
0,8
1
deformation
C
O
N
T
R
has
in
T
E
(
M
P
has
)
Coefficient for viscous law
VISC_SINH
MPa
6176
0
=
13
0
10
483
3.31131121
=
76
.
6
=
m
Coefficients of the model of Rousselier
used to obtain the solution of
reference
9
0
10
5
-
=
F
0001
.
0
=
D
MPa
1575
1
=

1.3
Boundary conditions and loadings
Because of symmetry, vertical displacements are locked for side P0P1 is DY=0.
Side P8P9 is subjected to a displacement imposed U
D
= 1 Misters.
The loading is imposed using 500 pitches of time in T=1000s for the slow case and T=0.001s for
the fast case.


2
Reference solution
2.1
Results of reference
The reference solution is obtained by carrying out same calculation with the model of Rousselier in
viscous version (
COMP_INCR
=
“ROUSS_VISC”
,
DEFORMATION
=
“PETIT_REAC”
) of which them
parameters were selected in order to return the effect of negligible porosity.
One compares the contraction of the ligament, i.e. displacement following X of the P1 node like
resulting effort (
REAC_NODA
) on face P8P9. One is interested in 3 values of displacement U
D
:
0.05mm, 0.5mm and 1mm.
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Code_Aster
®
Version
7.3
Titrate:
SSNA113 - Notched sample in viscoplasticity
Date
:
13/10/04
Author (S):
S. MICHEL-PONNELLE, A. PARROT
Key
:
V6.01.113-A
Page:
4/6
Manual of Validation
V6.01 booklet: Nonlinear statics into axisymmetric
HT-66/04/005/A
3 Modeling
With
3.1
Characteristics of modeling
·
Modeling
AXIS_SI
3.2
Characteristics of the mesh
The mesh is obtained by GIBI.
A number of nodes: 1440
A number of meshs: 445 QUAD8

3.3 Functionalities
tested
Controls
AFFE_MODELE AFFE
MODELING
AXIS_SI
DEFI_MATERIAU TRACTION
VISC_SINH
STAT_NON_LINE COMP_INCR
VMIS_ISOT_TRAC_V
DEFORMATION
SIMO_MIEHE


4
Results of modeling A
Fast speed
Identification displacement
Reference
Aster
% difference
U =0.05 mm
REAC_NODA
on P8P9
3.43132 10
3
3.42727 10
3
- 0.12
U
y
in P1
- 8.0411 10
- 3
- 8.09476 10
- 3
0.67
U =0.5 mm
REAC_NODA
on P8P9
3.93495 10
3
3.92628 10
3
- 0.22
U
y
in P1
- 4.06758 10
- 1
- 4.06649 10
- 1
- 0.03
U =1 mm
REAC_NODA
on P8P9
3.17328 10
3
3.16438 10
3
- 0.28
U
y
in P1
- 8.89457 10
- 1
- 8.89189 10
- 1
- 0.03
Slow speed
Identification displacement
Reference
Aster
% difference
U =0.05 mm
REAC_NODA
on P8P9
2.86423 10
3
2.86076 10
3
- 0.12
U
y
in P1
- 1.52635 10
- 2
- 1.52998 10
- 2
0.24
U =0.5 mm
REAC_NODA
on P8P9
3.36223 10
3
3.35580 10
3
- 0.19
U
y
in P1
- 4.19637 10
- 1
- 4.19497 10
- 1
- 0.03
U =1 mm
REAC_NODA
on P8P9
2.73903 10
3
2.73204 10
3
- 0.26
U
y
in P1
- 9.14404 10
- 1
- 9.14069 10
- 1
- 0.04
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Code_Aster
®
Version
7.3
Titrate:
SSNA113 - Notched sample in viscoplasticity
Date
:
13/10/04
Author (S):
S. MICHEL-PONNELLE, A. PARROT
Key
:
V6.01.113-A
Page:
5/6
Manual of Validation
V6.01 booklet: Nonlinear statics into axisymmetric
HT-66/04/005/A
5
Summary of the results
One obtains a good agreement of the results between the 2 models with lower deviations than 1%.
At the total level, one notes that to the maximum 4 iterations are necessary to obtain convergence.
On the level of the integration of the law of behavior, less than 10 iterations are necessary for
to obtain an accuracy of 10
- 9
.

background image
Code_Aster
®
Version
7.3
Titrate:
SSNA113 - Notched sample in viscoplasticity
Date
:
13/10/04
Author (S):
S. MICHEL-PONNELLE, A. PARROT
Key
:
V6.01.113-A
Page:
6/6
Manual of Validation
V6.01 booklet: Nonlinear statics into axisymmetric
HT-66/04/005/A

























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