Code_Aster ®
Version
5.0
Titrate:
Thermal TTLL301 Transfert in a bar with imposed temperature
Date:
20/09/02
Author (S):
C. DURAND, E. SCREW, F. LEBOUVIER Clé
:
V4.21.301-A Page:
1/8

Organization (S): EDF/AMA, EDF/UTO/LOCATED, Delta CAD
Handbook of Validation
V4.21 booklet: Transitory thermics of the linear structures
V4.21.301 document

TTLL301 - Thermal Transfert 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.

Handbook of Validation
V4.21 booklet: Transitory thermics of the linear structures
HT-66/02/001/A

Code_Aster ®
Version
5.0
Titrate:
Thermal TTLL301 Transfert in a bar with imposed temperature
Date:
20/09/02
Author (S):
C. DURAND, E. SCREW, F. LEBOUVIER Clé
:
V4.21.301-A Page:
2/8

1
Problem of reference

1.1 Geometry
TB = 100 sin (T/40) °C
With
B
X
0.08
0.1


Dimensions in meters

1.2
Properties of material

= 35 W/m °C
thermal conductivity
CP = 440.5 J/kg °C specific heat
= 7200 kg/m3 mass
voluminal

1.3
Boundary conditions and loadings

· temperature imposed on point a: MT = 0 °C,
· temperature imposed on point b: TB = 100 sin (T/40) °C.

1.4 Conditions
initial

T = 0: T (X) = 0 °C

Handbook of Validation
V4.21 booklet: Transitory thermics of the linear structures
HT-66/02/001/A

Code_Aster ®
Version
5.0
Titrate:
Thermal TTLL301 Transfert in a bar with imposed temperature
Date:
20/09/02
Author (S):
C. DURAND, E. SCREW, F. LEBOUVIER Clé
:
V4.21.301-A Page:
3/8

2
Reference solution

2.1
Method of calculation used for the reference solution

The reference solution is that given in 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 and Standard (the U.K.)) :
“Standard The NAFEMS Benchmarcks”, TNSB rév 3, October 1990.

Handbook of Validation
V4.21 booklet: Transitory thermics of the linear structures
HT-66/02/001/A

Code_Aster ®
Version
5.0
Titrate:
Thermal TTLL301 Transfert in a bar with imposed temperature
Date:
20/09/02
Author (S):
C. DURAND, E. SCREW, F. LEBOUVIER Clé
:
V4.21.301-A Page:
4/8

3 Modeling
With

3.1
Characteristics of modeling

PLAN (TRIA3)

y
D
C
N18
.01 m
X
With
.08
N17
B
.1
Limiting conditions:
- dimensioned AB CD = 0
- dimensioned AD
= 0 °C
- dimensioned BC
T = 100 sin (T/40) °C


3.2
Characteristics of the grid

A number of nodes:
22
A number of meshs and types: 10 TRIA3

3.3 Functionalities
tested


Commands




!FORMULE
CALC_FONC_INTERP
Interpol
“INT”

AFFE_MODELE
THERMIQUE
PLAN
TOUT
AFFE_CHAR_THER_F
TEMP_IMPO

THER_LINEAIRE
TEMP_INIT
VALE

LIST_INST

RECU_CHAMP
INST


3.4 Remarks

The discretization in step of time is as follows:

5 steps for [0. , 1.0D+0] is T = 2.D-1
18 steps for [1.D+0, 1.0D+1] are T = 5.D-1
20 steps for [1.D+1, 2.0D+1] are T = 5.D-1
20 steps for [2.D+1, 3.0D+1] are T = 5.D-1
10 steps for [3.D+1, 3.5D+1] are T = 5.D-1
Handbook of Validation
V4.21 booklet: Transitory thermics of the linear structures
HT-66/02/001/A

Code_Aster ®
Version
5.0
Titrate:
Thermal TTLL301 Transfert in a bar with imposed temperature
Date:
20/09/02
Author (S):
C. DURAND, E. SCREW, F. LEBOUVIER Clé
:
V4.21.301-A Page:
5/8

4
Results of modeling A

4.1 Values
tested

Identification Reference
Aster
% difference
Tolerance
Temperature at the point:
T (°C)


X = 0.08 m with T = 32 S





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

Obstruction memory:
8 megawords
Time CPU To use: 4.57 seconds
Handbook of Validation
V4.21 booklet: Transitory thermics of the linear structures
HT-66/02/001/A

Code_Aster ®
Version
5.0
Titrate:
Thermal TTLL301 Transfert in a bar with imposed temperature
Date:
20/09/02
Author (S):
C. DURAND, E. SCREW, F. LEBOUVIER Clé
:
V4.21.301-A Page:
6/8

5 Modeling
B

5.1
Characteristics of modeling

Modeling: 3D (PENTA15)

Z
D H
With
E
y
0.01 m
N114
N115
N119
0.01 m
C
Limiting conditions:
G
N118
- face AEHD
X
= 0 °C
B
- face BFGC
T = 100 sin (T/40) °C
- others faces
F
= 0


5.2
Characteristics of the grid

A number of nodes:
148
A number of meshs and types: 20 PENTA15

5.3 Functionalities
tested


Commands




!FORMULE
CALC_FONC_INTERP
Interpol
“INT”

AFFE_MODELE
THERMIQUE
3D
TOUT
AFFE_CHAR_THER_F
TEMP_IMPO

THER_LINEAIRE
TEMP_INIT
VALE

LIST_INST

RECU_CHAMP
INST


5.4 Remarks

The discretization in step of time is as follows:

5 steps for [0. , 1.0D+0] is T = 2.D-1
18 steps for [1.D+0, 1.0D+1] are T = 5.D-1
20 steps for [1.D+1, 2.0D+1] are T = 5.D-1
20 steps for [2.D+1, 3.0D+1] are T = 5.D-1
10 steps for [3.D+1, 3.5D+1] are T = 5.D-1
Handbook of Validation
V4.21 booklet: Transitory thermics of the linear structures
HT-66/02/001/A

Code_Aster ®
Version
5.0
Titrate:
Thermal TTLL301 Transfert in a bar with imposed temperature
Date:
20/09/02
Author (S):
C. DURAND, E. SCREW, F. LEBOUVIER Clé
:
V4.21.301-A Page:
7/8

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

Obstruction memory:
8 megawords
Time CPU To use: 5.03 seconds
Handbook of Validation
V4.21 booklet: Transitory thermics of the linear structures
HT-66/02/001/A

Code_Aster ®
Version
5.0
Titrate:
Thermal TTLL301 Transfert in a bar with imposed temperature
Date:
20/09/02
Author (S):
C. DURAND, E. SCREW, F. LEBOUVIER Clé
:
V4.21.301-A Page:
8/8

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 (PLAN 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 command “!FORMULE”. 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 grid
for linear modeling would allow to obtain better results.

The results of modeling A are thus regarded as acceptable.

The principal interest of this test is its origin: NAFEMS.

Handbook of Validation
V4.21 booklet: Transitory thermics of the linear structures
HT-66/02/001/A

Outline document