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Code_Aster
®
Version
5.0
Titrate:
TTLP304 Transfer of heat in an orthotropic plate: imposed flows
Date:
20/09/02
Author (S):
C. DURAND,
E. SCREWS, F. LEBOUVIER
Key
:
V4.23.304-A
Page:
1/6
Manual of Validation
V4.23 booklet: Transitory thermics of the plane systems
HT-66/02/001/A
Organization (S):
EDF/AMA, EDF/UTO/LOCATED, Delta CAD















Manual of Validation
V4.23 booklet: Transitory thermics of the plane systems
V4.23.304 document



TTLP304 - Transfer of heat in a plate
orthotropic: imposed flows




Summary:

This test results from the validation independent of version 3 in linear transitory thermics.

It is about a problem plane 2D represented by a modeling (plane).

The functionalities tested are as follows:
·
plane thermal element,
·
orthotropic material,
·
transitory algorithm of thermics,
·
limiting conditions: imposed flow.

The interest of the test lies in the taking into account of an orthotropic material.

The results are compared with an analytical solution.
background image
Code_Aster
®
Version
5.0
Titrate:
TTLP304 Transfer of heat in an orthotropic plate: imposed flows
Date:
20/09/02
Author (S):
C. DURAND,
E. SCREWS, F. LEBOUVIER
Key
:
V4.23.304-A
Page:
2/6
Manual of Validation
V4.23 booklet: Transitory thermics of the plane systems
HT-66/02/001/A
1
Problem of reference
1.1 Geometry
X
y
L
y
= 5.4 m
With
D
B
C
T
O
(X, y, 0) = - 1.111°C
L
X
= 2.7 m

1.2
Properties of material
X
=
2.638 W/m °C
thermal conductivity along axis X
y
=
0.633 W/m °C
thermal conductivity along the axis y
C
1899.1
J/m
3
°C voluminal heat

1.3
Boundary conditions and loadings
Contour [AB], [BC], [CD]: T =
-
17.778°C
Side [AD]:
= 0

1.4 Conditions
initial
T (T = 0) =
-
1.111°C
background image
Code_Aster
®
Version
5.0
Titrate:
TTLP304 Transfer of heat in an orthotropic plate: imposed flows
Date:
20/09/02
Author (S):
C. DURAND,
E. SCREWS, F. LEBOUVIER
Key
:
V4.23.304-A
Page:
3/6
Manual of Validation
V4.23 booklet: Transitory thermics of the plane systems
HT-66/02/001/A
2
Reference solution
2.1
Method of calculation used for the reference solution
T X y T
B
N
X
L
J y
Ly
N
L
J
L
T
N
N
X
J
X
X
y
y
(,)
cos (
)
sin
exp
(
)
=
-
-
-
+










=
=
1
1
2
2
2
2
2
2
2
1
2
2
1
4
where
[
]
B
T
J
N
N
I
N
J
=
-
-
-
-
-




+
8
2
1
1
1
1
3 2 59
2
2
()
(
) (
)
(
)
T
T
I
O
=
+
5
9
32

Temperature in °F with T =1.2 hr (4320s)
2.7 ­ 15,6151­15,6480­15,7455­15,9049 ­ 16,1211 ­ 16,3876 ­ 16,6964 ­ 17,0381­17,4022 ­ 17,7778
2.4 ­ 15,6462­15,6786­15,7748­15,9318 ­ 16,1449 ­ 16,4076 ­ 16,7120 ­ 17,0487­17,4076 ­ 17,7778
2.1 ­ 15,7391­15,7700­15,8620­16,0122 ­ 16,2160 ­ 16,4673 ­ 16,7584 ­ 17,0805­17,4238 ­ 17,7778
1.8 ­ 15,8921­15,9208­16,0058­16,1447 ­ 16,3333 ­ 16,5657 ­ 16,8349 ­ 17,1328­17,4503 ­ 17,7778
1.5 ­ 16,1025­16,1279­16,2035­16,3269 ­ 16,4944 ­ 16,7009 ­ 16,9401 ­ 17,2048­17,4869 ­ 17,7778
1.2 ­ 16,3655­16,3869­16,4506­16,5547 ­ 16,6959 ­ 16,8700 ­ 17,0716 ­ 17,2947­17,5325 ­ 17,7778
0.9 ­ 16,6744­16,6911­16,7409­16,8222 ­ 16,9325 ­ 17,0685 ­ 17,2261 ­ 17,4004­17,5862 ­ 17,7778
0.6 ­ 17,0203­17,0318­17,0660­17,1218 ­ 17,1975 ­ 17,2909 ­ 17,3991 ­ 17,5187­17,6462 ­ 17,7778
0.3 ­ 17,3923­17,3982­17,4156­17,4440 ­ 17,4825 ­ 17,5300 ­ 17,5851 ­ 17,6459­17,7108 ­ 17,7778
0.0 ­ 17,7778­17,7778­17,7778­17,7778 ­ 17,7778 ­ 17,7778 ­ 17,7778 ­ 17,7778­17,7778 ­ 17,7778
Y
X
0.0
0.3
0.6
0.9
1.2
1.5
1.8
2.1
2.4
2.7
The values of reference are obtained with n=j=1000

2.2
Results of reference
T = 1.2hr (4320s): temperature at the following points:
·
in X = 0.0: for y = 0.6, 1.5, 2.7,
·
in X = 0.9: for y = 0.6, 1.5, 2.7,
·
in X = 1.8: for y = 0.6, 1.5, 2.7.

2.3
Uncertainty on the solution
Analytical solution.

2.4 References
bibliographical
[1]
J.C. Bruch Jr., G. Zyroloski, `Transient two-dimensional heat conduction problems solved by
the finite element method', Int. J. num. Meth. Engng, flight 8, n°3, p 481-494, 1974.
background image
Code_Aster
®
Version
5.0
Titrate:
TTLP304 Transfer of heat in an orthotropic plate: imposed flows
Date:
20/09/02
Author (S):
C. DURAND,
E. SCREWS, F. LEBOUVIER
Key
:
V4.23.304-A
Page:
4/6
Manual of Validation
V4.23 booklet: Transitory thermics of the plane systems
HT-66/02/001/A
3 Modeling
With
3.1
Characteristics of modeling
PLAN (QUAD4, TRIA3)
y
X
With
B
F
E
Limiting conditions
- dimensioned AB, BH, HE: T=-1.111°C
- dimensioned EFF, FG, GA:
= 0
Cutting:
- AB, GH, FE 9 elements
- AG, BH 5 elements
- GF, HE 4 elements
2.7 m
2.7 m
TRIA3
QUAD4
1.5m
G
H
3.2
Characteristics of the mesh
A number of nodes:
100
A number of meshs and types: 117 (45 QUAD4, 72 TRIA3)
3.3 Functionalities
tested
Controls
AFFE_MODELE
THERMICS
PLAN
ALL
DEFI_MATERIAU
THER_ORTH
AFFE_CHAR_THER_F
TEMP_IMPO
AFFE_CARA_ELEM
SOLID MASS
THER_LINEAIRE
TEMP_INIT
VALE
CARA_ELEM
LIST_INST
RECU_CHAMP
INST
3.4 Remarks
The discretization in pitch of time is as follows:
10 pitches for [0. , 5.00D0] is
T = 0.5
9 pitches for [5.00D0, 5.00D1] are
T = 5.
9 pitches for [5.00D1, 5.00D2] are
T = 50.
38 pitches for [5.00D2, 4.30D3] are
T = 100.
1 pitch for [4.30D3, 4.32D3] is
T = 20.
background image
Code_Aster
®
Version
5.0
Titrate:
TTLP304 Transfer of heat in an orthotropic plate: imposed flows
Date:
20/09/02
Author (S):
C. DURAND,
E. SCREWS, F. LEBOUVIER
Key
:
V4.23.304-A
Page:
5/6
Manual of Validation
V4.23 booklet: Transitory thermics of the plane systems
HT-66/02/001/A
4
Results of modeling A
4.1 Values
tested
Relative variation %
Absolute deviation
Identification Reference Aster difference tolerance difference
tolerance
Temperature
in
°F
X
=
0.0
N3 (y = 0.6)
-
17.0203
-
17.0146
-
0.033
1% 0.006 0.05
N6 (y = 1.5)
-
16.1025
-
16.0957
-
0.042
1% 0.007 0.05
N10 (y = 2.7)
-
15.6151
-
15.5784
-
0.235
1% 0.037 0.05
X = 0.9
N33 (y = 0.6)
-
17.1218
-
17.1167
0.029 1%
0.005
0.05
N36 (y = 1.5)
-
16.3269
-
16.3127
- 0.087 1%
0.014
0.05
N40 (y = 2.7)
-
15.9049
-
15.8905
-
0.091
1% 0.014 0.05
X = 1.8
N63 (y = 0.6)
-
17.3991
-
17.3961
-
0.017
1% 0.003 0.05
N66 (y = 1.5)
-
16.9401
-
16.9297
-
0.061
1% 0.010 0.05
N70 (y = 2.7)
-
16.6964
-
16.6930
-
0.020
1% 0.003 0.05

4.2 Parameters
of execution
Version: 5.03
Machine: SGI - ORIGIN 2000 - R12000
Overall dimension memory:
8 megawords
Time CPU To use: 4.11 seconds
background image
Code_Aster
®
Version
5.0
Titrate:
TTLP304 Transfer of heat in an orthotropic plate: imposed flows
Date:
20/09/02
Author (S):
C. DURAND,
E. SCREWS, F. LEBOUVIER
Key
:
V4.23.304-A
Page:
6/6
Manual of Validation
V4.23 booklet: Transitory thermics of the plane systems
HT-66/02/001/A
5
Summary of the results
The results obtained are satisfactory, the maximum change obtained is 0.235%.
For the points of observation selected, the variations are more important with the nodes belonging to
meshs TRIA3.