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Code_Aster
®
Version
3
Titrate:
HPLV101 - Homogenization of a homogeneous material
Date:
21/05/96
Author (S):
I. EYMARD, F. VOLDOIRE
Key:
V7.03.101-A
Page:
1/8
Manual of Validation
V7.03 booklet: Thermomechanical stationary linear of the voluminal systems
HI-75/96/032/A
Organization (S):
EDF/IMA/MN
Manual of Validation
V7.03 booklet: Thermomechanical stationary linear of the voluminal systems
V7.03.101 document
HPLV101 - Homogenization of a material
homogeneous
Summary:
This test tests, in a commonplace situation where the material is homogeneous, the thermal resolution of the problems
and mechanics stationary, with loadings corresponding to a variation in temperature and to one
imposed deformation, close to those corresponding to the elementary problems of the method
of periodic homogenization.
background image
Code_Aster
®
Version
3
Titrate:
HPLV101 - Homogenization of a homogeneous material
Date:
21/05/96
Author (S):
I. EYMARD, F. VOLDOIRE
Key:
V7.03.101-A
Page:
2/8
Manual of Validation
V7.03 booklet: Thermomechanical stationary linear of the voluminal systems
HI-75/96/032/A
1
Problem of reference
1.1 Geometry
1
Z
N6
With
B
C
X
y
N5
N4
0
N7
N1
N2
N3
N8
1
16.410
X y Z

N4
0 0 16.410
N8 1. 1. 16.410
N3 0.5 0 16.410
1.2
Material properties
E = 1.0 MPa
= 0.3
K = 1.0 W/(m.°C)
C
p
= 0 J/(°C.m
3
)
1.3
Boundary conditions and loadings
·
Mechanics 3D:
Plan Z = 0:
dz = 0
dx = 0, Dy = 0
for the membrane loading;
for the loading of bending
Plans y = 0, y = 1:
Dy = 0
Plans X = 0, X = 1:
dx = 0
Node: O
dz = 0
(for the only loading of bending)
Loading:
membrane deformation:
imposed uniform bending:
E
E
=




=




­ 1 0 0
0
0 0
0
0 0
0 0
0 0 0
0 0 0
Z
·
Mechanics 2D, stresses plane:
Center: X = 0
Node: O
dx = 0
Dy = 0
(these conditions do not correspond to the application of
method of homogenization).
Loading: deformation
E
=




­ 1 0 0
0
0 0
0
0 0
uniform imposed
·
Thermics 3D and 2D:
Plan X = 0
temp = 0
(this condition does not correspond to the application of
method of homogenization).
Loading: gradient
(
)
G
=
­,
1 0 0
imposed uniform.
background image
Code_Aster
®
Version
3
Titrate:
HPLV101 - Homogenization of a homogeneous material
Date:
21/05/96
Author (S):
I. EYMARD, F. VOLDOIRE
Key:
V7.03.101-A
Page:
3/8
Manual of Validation
V7.03 booklet: Thermomechanical stationary linear of the voluminal systems
HI-75/96/032/A
2
Reference solution
2.1
Method of calculation used for the reference solution
·
In thermics: the stationary thermal problem is solved:
=
=




T.
.
,
,
­
K
G K
G
V
with
1
0
0
Note:
The boundary conditions chosen here are not those necessary to the method
of homogenization: one would find indeed
T
=
0
everywhere.
The solution is then (checking the conditions defined in [§1.3]):
(
)
T X y Z
X
,
­
=
The potential energy is then with balance:
W
HT
T
T
=
=
­
.
­
1
2
1
2
K
here
·
In mechanics: one solves the problem of elastostatic:
()
()
()
U With
v
With
v
v
=
.
.
,
,
E
W
for the cases:
loading 3D
membrane
loading 3D
of bending
loading 2D
plane stresses
E
=




­ 1 0 0
0
0 0
0
0 0
E
=




Z 0 0
0 0 0
0 0 0
E
=




­ 1 0 0
0
0 0
0
0 0
The solutions are:
·
in 3D, membrane loading:
(
)
(
)
U X y Z
Z
,
, ­
­
=


0 0
1
;
the potential energy with balance is:
()
()
(
)
W
pot
=
=



+
­
.
­
­
.
1
2
1
2
2
2
µ
U With
U
·
in 3D, loading of bending:
(
)
(
)
U X y Z
Z
,
,
­
=
+






0 0 2 1
2
;
(
)
W
pot
H
=


+
­
­
.
.
µ
1
2
2
3
2
3
·
in 2D, plane loading:
()
(
)
U X y
X
,
­,
=
0
;
(
)
W
pot
=
­
­
2 1
2
background image
Code_Aster
®
Version
3
Titrate:
HPLV101 - Homogenization of a homogeneous material
Date:
21/05/96
Author (S):
I. EYMARD, F. VOLDOIRE
Key:
V7.03.101-A
Page:
4/8
Manual of Validation
V7.03 booklet: Thermomechanical stationary linear of the voluminal systems
HI-75/96/032/A
3 Modeling
With
3.1
Characteristics of modeling
y
N6
B
X
With
O
C
GRNM14
Boundary conditions and loading:
Thermics:
GROUP_NO: GRNM14: TEMP: 0.0
GRAD_TEMP_INIT: FLUX_X: ­ 1.0
Mechanics:
(plane stresses)
GROUP_NO: GRNM14: DX: 0.0
NODE: O DY: 0.0
EPSI_INIT: EPXX: ­ 1.0
3.2
Characteristics of the mesh
A number of nodes: 8
A number of meshs and types: 1 QUAD8
3.3 Functionalities
tested
Controls
Keys
AFFE_CHAR_THER
GRAD_TEMP_INIT
ALL
FLUX_X
“YES”
[U4.25.02]
AFFE_CHAR_MECA
EPSI_INIT
ALL
EPXX
“YES”
[U4.25.01]
POST_ELEM
ENER_POT
ALL
“YES”
[U4.61.04]
background image
Code_Aster
®
Version
3
Titrate:
HPLV101 - Homogenization of a homogeneous material
Date:
21/05/96
Author (S):
I. EYMARD, F. VOLDOIRE
Key:
V7.03.101-A
Page:
5/8
Manual of Validation
V7.03 booklet: Thermomechanical stationary linear of the voluminal systems
HI-75/96/032/A
4
Results of modeling A
4.1 Values
tested
Not
Size
CMP
Reference
Aster
% difference
Tolerance %
With
TEMP
­ 1.0000
­ 1.00000
0.000
10
­ 6
With
DX
­ 1.0000
­ 1.00000
0.000
10
­ 6
N6
DX
­ 0.5000
­ 0.50000
0.000
10
­ 6
Net
Energy
potential
with balance
Reference
Aster
% difference
M1
Thermics
­ 0.500000000
­ 0.500000
10
­ 8
M1
Mechanics
­ 0.549450550
+0.549451
10
­ 8
4.2 Remarks
Code_Aster provides the value of the deformation energy, equal contrary to the potential energy to
balance (elastic case).
4.3 Parameters
of execution
Version: 3.02.18
Machine: CRAY C90
System:
UNICOS 8.0
Overall dimension memory:
16 megawords
Time CPU To use:
3.7 seconds
background image
Code_Aster
®
Version
3
Titrate:
HPLV101 - Homogenization of a homogeneous material
Date:
21/05/96
Author (S):
I. EYMARD, F. VOLDOIRE
Key:
V7.03.101-A
Page:
6/8
Manual of Validation
V7.03 booklet: Thermomechanical stationary linear of the voluminal systems
HI-75/96/032/A
5 Modeling
B
5.1
Characteristics of modeling
Z
N2
N6
y
C
B
With
O
N8
N3
N4
X
Name of the meshs of the faces:
ZEGAL0
YEGAL0
YEGAL1
XEGAL0
XEGAL1
Summits:
B C O WITH
O WITH N2 N4 B C N6 N8
C O N4 N6 A B N8 N2
Boundary conditions:
Thermics:
ZERO: DEFI_CONSTANTE (VALE: 0.0);
FCT1:DEFI_FONCTION (Nom_para:“Z”, VALE: (0.0 0.0.1.0.1.0));
GROUP_NO: XEGAL0: TEMP: 0.0
GRAD_TEMP_INIT: FLUX_X: - 1.0
Mechanics:
GROUP_NO: YEGALO: DY = 0.0
XEGAL1: DX = 0.0
YEGAL1: DY = 0.0
XEGALO: DZ = 0.0
Membrane case:
GROUP_NO: ZEGALO: DZ = 0.0
EPSI_INIT: EPXX: - 1.0
Case bending:
GROUP_NO: ZEGALO: DX = ZERO, DY = ZERO
NODE: 0 DZ = ZERO
EPSI_INIT: EPXX: FCT1
5.2
Characteristics of the mesh
A number of nodes: 20
A number of meshs and types: 1 HEXA20
5.3 Functionalities
tested
Controls
Keys
AFFE_CHAR_THER
GRAD_TEMP_INIT
ALL
FLUX_X
[U4.25.02]
AFFE_CHAR_MECA
EPSI_INIT
EPXX
[U4.25.01]
AFFE_CHAR_MECA_F
EPSI_INIT
EPXX
[U4.25.01]
POST_ELEM
ENER_POT
ALL
“YES”
[U4.61.04]
background image
Code_Aster
®
Version
3
Titrate:
HPLV101 - Homogenization of a homogeneous material
Date:
21/05/96
Author (S):
I. EYMARD, F. VOLDOIRE
Key:
V7.03.101-A
Page:
7/8
Manual of Validation
V7.03 booklet: Thermomechanical stationary linear of the voluminal systems
HI-75/96/032/A
6
Results of modeling B
6.1 Values
tested
Case
Size
Not
Reference
Aster
% difference
Thermics
temp
N8
­ 1.000000
­ 1.000000
10
­ 10
temp
N3
­ 0.500000
­ 0.5000000
10
­ 10
Mechanics
dz
N4
­ 7.03285714
­ 7.03285714
10
­ 10
membrane
dz
N8
­ 7.03285714
­ 7.03285714
10
­ 10
Mechanics
dz
N4
57.70459285
57.70459285
10
­ 10
bending
dz
N8
57.70459285
57.70459285
10
­ 10
Net
Energy
potential
with balance
Reference
Aster
% difference
M1
Thermics
­ 8.20500
­ 8.20500
10
­ 7
M1
Mechanics
Membrane
Bending
­ 2.0287088
­ 1.8210238 10
2
­ 2.02871
­ 1.82102 10
2
10
­ 7
10
­ 7
6.2 Parameters
of execution
Version: 3.05.30
Machine: CRAY C90
System:
UNICOS 8.0
Overall dimension memory:
16 megawords
Time CPU To use:
16.51 seconds
background image
Code_Aster
®
Version
3
Titrate:
HPLV101 - Homogenization of a homogeneous material
Date:
21/05/96
Author (S):
I. EYMARD, F. VOLDOIRE
Key:
V7.03.101-A
Page:
8/8
Manual of Validation
V7.03 booklet: Thermomechanical stationary linear of the voluminal systems
HI-75/96/032/A
7
Summary of the results
The results are exact with round-off errors close, since the sought solutions belong to
the space of the finite elements selected for modeling.