1 Search for Worst-Case Forces MICE Video Conference, September 8, 2004 Yury Ivanyushenkov Applied...
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Transcript of 1 Search for Worst-Case Forces MICE Video Conference, September 8, 2004 Yury Ivanyushenkov Applied...
1
Search for Worst-Case ForcesSearch for Worst-Case Forces
MICE Video Conference, September 8, 2004
Yury Ivanyushenkov
Applied Science Division,Engineering and Instrumentation Department,
RAL
2
Aims of workGoal: find maximal (static and dynamical) possible forces in MICE magnetic system.
Method: calculation of axial magnetic forces in MICE by using OPERA package (and other codes).
Cases to be analyzed: - MICE stages III, IV, V and VI (see next slide): Parameters (proposal): magnetic modes - flip, semi-flip and non-flip; momentum (MeV/c) – 140, 170, 200, 240; beta (cm) – 7, 15, 25, 42; gap focus coil – match coil (mm) - 450 (was 600); coil currents - 0 (coil is off or quenched), nominal, max (critical current ?); magnetic shielding – with and without. - Abnormal cases: - dynamical forces during quenches; - anything else?
3
STEP I:
STEP II
STEP III
STEP IV
STEP V
STEP VI
By A.Blondel
MICE stages
4
Model (without shielding) in OPERA
Model:-18 coils;- no iron shielding
5
255 305
126012060
200
620
263347725
250
841
13751385 12501260
3660
(SFOFO, 200 MeV/c, beta=42 cm, gap =600 mm)
404
Centre coils: J=64.44 A/mm2
Focusing coils: J=113.95 A/mm2
Coupling coils: J=96.21 A/mm2
End #2 coils: J=67.11 A/mm2
255355
202
Matching #2 coils: J=41.46 A/mm2
2440
202
45414721
6041
6161
Matching #1 coils: J=65.06 A/mm2
End #1 coils: J=65.22 A/mm2
792
305
Gap=600
MICE magnetic system geometry
Note:Geometry and currents fromUlisse before Osaka meeting
6
(SFOFO, p=200 MeV/c, beta=42 cm, gap =450 mm)
4.1 4.1
83.9 13.9
20.8235
228
14236
83.9
13.9
20.8
235
228
14
236
All forces are in tonnes !
147 147
Centre coils: J=64.44 A/mm2
Coupling coils: J=96.21 A/mm2
End #2 coils: J=67.11 A/mm2
Matching #2 coils: J=75.17 A/mm2
Matching #1 coils: J=56.30 A/mm2
End #1 coils: J=61.59 A/mm2
Focusing coils: J=113.95 A/mm2
24.3 7
Forces in MICE magnetic system
14
7
2.4 103.5
6.6 22
220225
15.4236 147
12.5 5 15.4
4.1 83.9
13.9 20.8
235228
14236 147
24.3 714
(SFOFO, p=200 MeV/c, beta=42 cm, gap =600 mm)
(SFOFO, p=200 MeV/c, beta=42 cm, gap =450 mm)
Forces Vs. Gap for p=200 Mev/c
8
(SFOFO, p=240 MeV/c, beta=42 cm, gap =450 mm)
2.4 2.4
79 9
23.3
336.6
328
21.5340
79
9
23.3
336.6
328
21.5
340
All forces are in tonnes !
147
Centre coils: J=64.44 A/mm2
Coupling coils: J=115.45 A/mm2
End #2 coils: J=67.11 A/mm2
Matching #2 coils: J=83.07 A/mm2
Matching #1 coils: J=66.82 A/mm2
End #1 coils: J=61.59 A/mm2
Focusing coils: J=136.74 A/mm2
147
33.3 8.6
Forces in MICE magnetic system
21.5
9
Forces Vs. p for gap=450 mm(SFOFO, p=200 MeV/c, beta=42 cm, gap =450 mm)
(SFOFO, p=240 MeV/c, beta=42 cm, gap =450 mm)
2.4 79
9 23.3
336.6328
21.5340 147
33.3 8.6 21.5
4.1 83.9
13.9 20.8
235228
14236
All forces are in tonnes !
147
24.3 714
10
(SEMI-FLIP, p=200 MeV/c, beta=42 cm, gap =600 mm)
2.2 2.2
100.8 3.6
14 59.5
46
46.797
100.8
3.6
14
59.5
46
46.7
97
All forces are in tonnes !
146
Centre coils: J=63.81 A/mm2
Coupling coils: J=93.10 A/mm2
End #2 coils: J=67.11 A/mm2
Matching #2 coils: J=34.99 A/mm2
Matching #1 coils: J=68.33 A/mm2
End #1 coils: J=64.01 A/mm2
Focusing coils: J=68.03 A/mm2
146
39.4 13.5
Forces in MICE magnetic system
46.7
11
(NON-FLIP, p=200 MeV/c, beta=42 cm, gap =600 mm)
1.8 1.8
100.6 3.6
13.7 60.3
45
15.751.5
100.6
3.6
13.7
60.3
45
15.7
51.5
All forces are in tonnes !
146
Centre coils: J=63.81 A/mm2
Coupling coils: J=93.10 A/mm2
End #2 coils: J=67.11 A/mm2
Matching #2 coils: J=34.99 A/mm2
Matching #1 coils: J=68.33 A/mm2
End #1 coils: J=64.01 A/mm2
Focusing coils: J=68.03 A/mm2
146
26.3 15.3
Forces in MICE magnetic system
15.7
12
Net Force, tonne / Case
SFOFO, p=200 Mev/c, beta=42 cm
SFOFO, p=240 Mev/c, beta=42 cm
SEMI-FLIP, p=200 Mev/c,
beta=42 cm
NON-FLIP, p=200 Mev/c,
beta=42 cm
Gap=450 mm
Gap=600 mm
Gap=450 mm
Gap=600 mm
Gap=600 mm
Gap=600 mm
Central focus pair 0 0 0 0 0 0
Edge focus pair 7from centre
5towards centre
8.6from centre
8towards centre
13.5towards centre
15.3towards centre
Coupling coil 14from centre
15from centre
21.5from centre
23from centre
46.7from centre
15.7towards centre
Tracker solenoid 24.3towards centre
12.5towards centre
33.3towards centre
17.3towards centre
39.4towards centre
26.3towards centre
Summary table for axial magnetic forces
13
(SFOFO, p=240 MeV/c, beta=42 cm, gap =450 mm, Focus Coils quenched)
3.4 3.4
80.3 12.1
57.5
0
0
21.1 0
80.3
12.1
57.5
0
0
21.1
0
All forces are in tonnes !
Centre coils: J=64.44 A/mm2
Coupling coils: J=115.45 A/mm2
End #2 coils: J=67.11 A/mm2
Matching #2 coils: J=83.07 A/mm2
Matching #1 coils: J=66.82 A/mm2
End #1 coils: J=61.59 A/mm2
Focusing coils: J=0 A/mm2
147
6.3 0
Forces in MICE magnetic system: Quenches
21.1
147
14
(SFOFO, p=240 MeV/c, beta=42 cm, gap =450 mm, Focus Coils quenched)
3.4 80.3
12.1 57.5
0
0
21.1 0
All forces are in tonnes !
6.3 0
Forces in MICE magnetic system: Quenches (2)
21.1
147
(SFOFO, p=240 MeV/c, beta=42 cm, gap =450 mm)
2.4 79
9 23.3
336.6328
21.5340
33.3 8.6 21.5
15
(SFOFO, p=240 MeV/c, beta=42 cm, gap =450 mm,
Coupling Coils quenched)
0.8 0.8
77.8 7.8
19
312.7
273
0259.7
77.8
7.8
19
312.7
273
0
259.7
All forces are in tonnes !
147.3
Centre coils: J=64.44 A/mm2
Coupling coils: J=0 A/mm2
End #2 coils: J=67.11 A/mm2
Matching #2 coils: J=83.07 A/mm2
Matching #1 coils: J=66.82 A/mm2
End #1 coils: J=61.59 A/mm2
Focusing coils: J=136.74 A/mm2
147.3
43.5 39.7
Forces in MICE magnetic system: Quenches (3)
0
16
Forces in MICE magnetic system: Quenches (4)
(SFOFO, p=240 MeV/c, beta=42 cm, gap =450 mm,
Coupling Coils quenched)
0.8 77.8
7.8 19
312.7
273
0259.7
All forces are in tonnes !
43.5 39.7 0
147.3
(SFOFO, p=240 MeV/c, beta=42 cm, gap =450 mm)
2.4 79
9 23.3
336.6328
21.5340
33.3 8.6 21.5
17
(SFOFO, p=240 MeV/c, beta=42 cm, gap =450 mm,
Detector Magnets quenched)
0 0
0 0
0
283.6
314.8
31.3340.7
0
0
0
283.6
314.8
31.3
340.7
All forces are in tonnes !
0
Centre coils: J=0 A/mm2
Coupling coils: J=115.45 A/mm2
End #2 coils: J=0 A/mm2
Matching #2 coils: J=0 A/mm2
Matching #1 coils: J=0 A/mm2
End #1 coils: J=0 A/mm2
Focusing coils: J=136.74 A/mm2
0
0 31.2
Forces in MICE magnetic system: Quenches (5)
31.3
18
(SFOFO, p=240 MeV/c, beta=42 cm, gap =450 mm,
Detector Magnets quenched)
0 0
0 0
283.6
314.8
31.3340.7
All forces are in tonnes !
0
0 31.2 31.3
Forces in MICE magnetic system: Quenches (6)
(SFOFO, p=240 MeV/c, beta=42 cm, gap =450 mm)
2.4 79
9 23.3
336.6328
21.5340
33.3 8.6 21.5
19
Net Force, tonne / Case Normal mode
Coils quenched:
Focus coils Coupling coils
Detector magnets
Central focus pair 0 0 0 0
Edge focus pair 8.6from centre
0 39.7from centre
31.2towards centre
Coupling coil 21.5from centre
21.1from centre
0 31.3from centre
Tracker solenoid 33.3towards centre
6.3from centre
43.5towards centre
0
Summary table for axial magnetic forces: Quench cases SFOFO, p=240 Mev/c, beta=42 cm, gap=450 mm
20
Forces in MICE magnetic system: Effect of shielding disks
2.4 103.5
6.6 22
220225
15.4236 147
12.5 5 15.4
(SFOFO, p=200 MeV/c, beta=42 cm, gap =600 mm)
5.0 103.6
6.7 22
220225
15.4236 139.9
2.6 515.4
Without shielding disks
With shielding disks
21
Conclusions
Conclusions (preliminary):
• so far, the highest net forces on modules are created in SEMI-FLIP mode (but the highest net force on the edge focus pair is in case of NON-FLIP mode) -> it seems there is no a single worst case for all the modules;
• for FLIP mode forces are the highest for 240 MeV/c;
• both the edge focus pair and the tracker solenoid (but not the coupling coil) are sensitive to the value of the gap;
• forces change when some of coils are quenched;
• shielding disks change forces on the detector module
22
Next steps
New set of currents for various MICE stages and magnetic modes has been recently released by Ulisse Bravar.
Proposal for the next steps:
• agree on parameter space for force cases;• get from Ulisse a complete set of currents (and geometries) for all stages and magnetic modes;• ask John Cobb to make a quick scan of parameter space by using his code to indicate the worst cases;• check worst cases with OPERA including shielding in the model;• collect recommendations from the Collaboration on abnormal cases and include these cases into the analysis;• dynamical cases – ask for help from magnet experts;• anything else ?