Code_Aster
®
Version
5.0
Titrate:
Thermal TTLL301 Transfer in a bar with imposed temperature
Date:
20/09/02
Author (S):
C. DURAND, E. SCREW, F. LEBOUVIER
Key
:
V4.21.301-A
Page:
1/8
Manual of Validation
V4.21 booklet: Transitory thermics of the linear structures
HT-66/02/001/A
Organization (S):
EDF/AMA, EDF/UTO/LOCATED, Delta CAD
Manual of Validation
V4.21 booklet: Transitory thermics of the linear structures
V4.21.301 document
TTLL301 - Thermal transfer in a bar with
imposed temperature (sinusoid)
Summary:
This test results from the validation independent of version 3 in linear transitory thermics.
It is about a linear problem 1D represented by two modelings, one planes, the other voluminal one.
The functionalities tested are as follows:
plane thermal element,
voluminal thermal element,
transitory algorithm of thermics,
limiting conditions: sinusoidal variation of the temperature imposed in the course of time.
·
The interest of the test lies in the taking into account of the variation in the temperature imposed during
time and of the geometrical discretization.
The results are compared with those provided by NAFEMS.
Code_Aster
®
Version
5.0
Titrate:
Thermal TTLL301 Transfer in a bar with imposed temperature
Date:
20/09/02
Author (S):
C. DURAND, E. SCREW, F. LEBOUVIER
Key
:
V4.21.301-A
Page:
2/8
Manual of Validation
V4.21 booklet: Transitory thermics of the linear structures
HT-66/02/001/A
1
Problem of reference
1.1 Geometry
0.1
With
B
T
B
= 100 sin (
T/40) °C
X
0.08
Dimensions in meters
1.2
Properties of material
= 35 W/m °C
thermal conductivity
C
p
= 440.5 J/kg °C specific heat
=
7200 kg/m
3
mass
voluminal
1.3
Boundary conditions and loadings
·
temperature imposed on point a: T
With
= 0 °C,
·
temperature imposed on point b: T
B
= 100 sin (
T/40) °C.
1.4 Conditions
initial
T = 0: T (X) = 0 °C
Code_Aster
®
Version
5.0
Titrate:
Thermal TTLL301 Transfer in a bar with imposed temperature
Date:
20/09/02
Author (S):
C. DURAND, E. SCREW, F. LEBOUVIER
Key
:
V4.21.301-A
Page:
3/8
Manual of Validation
V4.21 booklet: Transitory thermics of the linear structures
HT-66/02/001/A
2
Reference solution
2.1
Method of calculation used for the reference solution
The reference solution is that given in the card “TEST n° T3” of the tests of reference published
by NAFEMS.
2.2
Results of reference
Temperature as in point X = 0.08 at the moment T = 32 S
2.3
Uncertainty on the solution
Nonavailable on card NAFEMS.
2.4 References
bibliographical
[1]
NAFEMS (the National Agency for Finite Element Methods Standard and (the U.K.)) :
“Standard The NAFEMS Benchmarcks”, TNSB rév 3, October 1990.
Code_Aster
®
Version
5.0
Titrate:
Thermal TTLL301 Transfer in a bar with imposed temperature
Date:
20/09/02
Author (S):
C. DURAND, E. SCREW, F. LEBOUVIER
Key
:
V4.21.301-A
Page:
4/8
Manual of Validation
V4.21 booklet: Transitory thermics of the linear structures
HT-66/02/001/A
3 Modeling
With
3.1
Characteristics of modeling
PLAN (TRIA3)
D
B
With
y
X
Limiting conditions:
- dimensioned AB CD
= 0
- dimensioned AD
= 0 °C
- dimensioned BC
T = 100 sin (
T/40) °C
.01 m
C
.08
.1
N17
N18
3.2
Characteristics of the mesh
A number of nodes:
22
A number of meshs and types: 10 TRIA3
3.3 Functionalities
tested
Controls
!FORMULATE
CALC_FONC_INTERP
Interpol
“INT”
AFFE_MODELE
THERMICS
PLAN
ALL
AFFE_CHAR_THER_F
TEMP_IMPO
THER_LINEAIRE
TEMP_INIT
VALE
LIST_INST
RECU_CHAMP
INST
3.4 Remarks
The discretization in pitch of time is as follows:
5 pitches for [0. , 1.0D+0] is
T = 2.D-1
18 pitches for [1.D+0, 1.0D+1] are
T = 5.D-1
20 pitches for [1.D+1, 2.0D+1] are
T = 5.D-1
20 pitches for [2.D+1, 3.0D+1] are
T = 5.D-1
10 pitches for [3.D+1, 3.5D+1] are
T = 5.D-1
Code_Aster
®
Version
5.0
Titrate:
Thermal TTLL301 Transfer in a bar with imposed temperature
Date:
20/09/02
Author (S):
C. DURAND, E. SCREW, F. LEBOUVIER
Key
:
V4.21.301-A
Page:
5/8
Manual of Validation
V4.21 booklet: Transitory thermics of the linear structures
HT-66/02/001/A
4
Results of modeling A
4.1 Values
tested
Identification Reference
Aster
% difference
Tolerance
Temperature at the point:
X = 0.08 m with T = 32 S
T (°C)
N17 36.60
37.87
3.480
2%
N18 36.60
36.98
1.036
2%
4.2 Parameters
of execution
Version: 5.03
Machine: SGI - ORIGIN 2000 - R12000
Overall dimension memory:
8 megawords
Time CPU To use: 4.57 seconds
Code_Aster
®
Version
5.0
Titrate:
Thermal TTLL301 Transfer in a bar with imposed temperature
Date:
20/09/02
Author (S):
C. DURAND, E. SCREW, F. LEBOUVIER
Key
:
V4.21.301-A
Page:
6/8
Manual of Validation
V4.21 booklet: Transitory thermics of the linear structures
HT-66/02/001/A
5 Modeling
B
5.1
Characteristics of modeling
Modeling: 3D (PENTA15)
Limiting conditions:
- face AEHD
= 0 °C
- face BFGC
T = 100 sin (
T/40) °C
- others faces
= 0
G
B
E
F
Z
X
H
y
C
With
D
0.01 m
0.01 m
N119
N118
N114
N115
5.2
Characteristics of the mesh
A number of nodes:
148
A number of meshs and types: 20 PENTA15
5.3 Functionalities
tested
Controls
!FORMULATE
CALC_FONC_INTERP
Interpol
“INT”
AFFE_MODELE
THERMICS
3D
ALL
AFFE_CHAR_THER_F
TEMP_IMPO
THER_LINEAIRE
TEMP_INIT
VALE
LIST_INST
RECU_CHAMP
INST
5.4 Remarks
The discretization in pitch of time is as follows:
5 pitches for [0. , 1.0D+0] is
T = 2.D-1
18 pitches for [1.D+0, 1.0D+1] are
T = 5.D-1
20 pitches for [1.D+1, 2.0D+1] are
T = 5.D-1
20 pitches for [2.D+1, 3.0D+1] are
T = 5.D-1
10 pitches for [3.D+1, 3.5D+1] are
T = 5.D-1
Code_Aster
®
Version
5.0
Titrate:
Thermal TTLL301 Transfer in a bar with imposed temperature
Date:
20/09/02
Author (S):
C. DURAND, E. SCREW, F. LEBOUVIER
Key
:
V4.21.301-A
Page:
7/8
Manual of Validation
V4.21 booklet: Transitory thermics of the linear structures
HT-66/02/001/A
6
Results of modeling B
6.1 Values
tested
Identification Reference
Aster
% difference
Tolerance
Temperature at the point:
X = 0.08 m with T = 32 S
N114 36.60
36.60
0.006
2%
N115 36.60
36.47
-
0.355
2%
N118 36.60
36.47
-
0.355
2%
N119 36.60
36.60
0.006
2%
6.2 Parameters
of execution
Version: 5.03
Machine: SGI - ORIGIN 2000 - R12000
Overall dimension memory:
8 megawords
Time CPU To use: 5.03 seconds
Code_Aster
®
Version
5.0
Titrate:
Thermal TTLL301 Transfer in a bar with imposed temperature
Date:
20/09/02
Author (S):
C. DURAND, E. SCREW, F. LEBOUVIER
Key
:
V4.21.301-A
Page:
8/8
Manual of Validation
V4.21 booklet: Transitory thermics of the linear structures
HT-66/02/001/A
7
Summary of the results
This test is recommended by NAFEMS (but with another type of mesh).
Two modelings carried out give the following results:
·
modeling A (PLANE with meshs TRIA3), the maximum change (3.48%) is higher than
tolerance fixed initially (2%),
·
modeling B (3D with meshs PENTA15), the maximum change (0.36%) is lower than
tolerance fixed initially (2%).
The limiting condition is given by using the control “
!FORMULATE
“. This choice allows good
representation of the taking into account of the condition limits of sinusoidal form.
Quadratic modeling is adapted to simulate this test. A finer and balanced mesh
for linear modeling would allow to obtain better results.
The results of modeling A are thus regarded as acceptable.
The main interest of this test is its origin: NAFEMS.