slac damage tests
DESCRIPTION
SLAC Damage Tests. Used pulse time of 1ps, with a gap of 0.1s between pulses. Used heat deposition file supplied by Luis using the very fine mesh on a small volume. Studied the .010TRANSCRIPT
1G.E. Ellwood
Advanced Materials Group 1
SLAC Damage Tests
• Used pulse time of 1ps, with a gap of 0.1s between pulses.
• Used heat deposition file supplied by Luis using the very fine mesh on a small volume.
• Studied the .010<z<.015m range.
• Used the same mesh, 20x20x120μm.
• Coupled Field elements.
2G.E. Ellwood
Advanced Materials Group 2
1st example
-.015m < z < .015m
2nd Example
.010m < z < .015m
The peak temperature rise is
only seen in the .010m < z
< .015m
region.
What happens on the other region has very little effect on the peak values. This reduces the number of elements needed significantly.
3G.E. Ellwood
Advanced Materials Group 3
0
5
10
15
20
25
30
0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0.18 0.20
Time (s)
Tem
per
atu
re (
°C)
Tem
p.
rise=
17.5
°C
Tem
p.
rise=
16.6
°C
Temp. loss = 10.7°C
Temp. loss = 10.8°C
Temperature v. Time at Hottest Node
Initial run with coarse mesh
Maximum temperature is a lot lower than would be seen with a finer mesh.
4G.E. Ellwood
Advanced Materials Group 4
Comparison – Hottest Node
0
50
100
150
200
250
0.00E+00 2.00E-13 4.00E-13 6.00E-13 8.00E-13 1.00E-12 1.20E-12
Time (s)
Tem
pera
ture
(°C
)
Full range
Reduced Z
Plotted temperature at hottest node during the first bunch heating, which used the same heating regime.
Hottest nodes had the same global location, but different numbering due to meshing.
The temperatures were exactly the same, despite the different geometry.
5G.E. Ellwood
Advanced Materials Group 5
0
50
100
150
200
250
300
0 0.02 0.04 0.06 0.08 0.1 0.12
Time (s)
Tem
pera
ture
(°C
)
Tem
p. r
ise
= 2
33.0
2°C
Tem
p. r
ise
= 2
33.3
17°C
Smaller time steps are required in this region
Heat loss = 197.482°C
6G.E. Ellwood
Advanced Materials Group 6
7G.E. Ellwood
Advanced Materials Group 7
Coarse v. Fine mesh – relative to highest value
8G.E. Ellwood
Advanced Materials Group 8
0.00E+00 2.00E-07 4.00E-07 6.00E-07 8.00E-07 1.00E-06 1.20E-06
Time (s)
0
50
100
150
200
250
300
350
400
450
500
0.00E+00 2.00E-02 4.00E-02 6.00E-02 8.00E-02 1.00E-01 1.20E-01
Te
mp
era
ture
(°C
)
337ns bunch gap0.1 bunch gap
9G.E. Ellwood
Advanced Materials Group 9
0.00E+00
1.00E+07
2.00E+07
3.00E+07
4.00E+07
5.00E+07
6.00E+07
7.00E+07
8.00E+07
9.00E+07
0.00E+00 2.00E-02 4.00E-02 6.00E-02 8.00E-02 1.00E-01 1.20E-01
Time (s)
Von
Mis
es S
tres
s (M
Pa)