1 progress on the mice cooling channel solenoid magnet system m.a. green, s. q. yang, g. barr, u....
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Progress on the MICE Cooling Channel Solenoid Magnet System
M.A. Green, S. Q. Yang, G. Barr, U. Bravar, J. Cobb W. W. Lau, R.S. Senenayake,
H. Witte, A. E. White Physics Department, Oxford University, UK
D. Li and S. P. VorostekLawrence Berkeley Laboratory, Berkeley USA
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• Introduction of MICE Cooling Channel• MICE Absorber Focusing Coil module• The Focusing Magnet Design• FEA Models of the Focusing magnet • MICE RF and Coupling Coil module• The Coupling Magnet design• FEA Models of the Coupling Magnet• Tasks Completed and Tasks to Do • Conclusion
Outline
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Focusing and Coupling Magnet ReportsM. A. Green and S. Q. Yang, “Heat Transfer into and within the 4.4 K Region and the 40 K Shields of the MICE Focusing and Coupling Magnets” Oxford University Physics Report, 28 April 2004
M. A. Green and R. S. Senanayake, “The Cold Mass Support System for the MICE Focusing and Coupling Magnets,” Oxford University Physics Report, 23 August 2004
M. A. Green and S. Q. Yang, “The Coil and Support Structure Stress and Strain the MICE Focusing and Coupling Magnets,” Oxford University Physics Report, 30 August 2004
M. A. Green, “Cooling the MICE Magnets using Small Cryogenic Coolers,” Oxford University Physics Report, 10 September 2004
S. Q Yang, M. A. Green, G. Barr, et al, “The Mechanical and Thermal Design for the MICE Focusing Solenoid Magnet System,” submitted to IEEE Transactions on Applied Superconductivity 15, (2005), submitted 5 Oct. 05
M. A. Green, S. Q. Yang, U. Bravar, et al, ““The Mechanical and Thermal Design for the MICE Coupling Solenoid Magnet,” submitted to IEEE Transactions on Applied Superconductivity 15 (2005), submitted 5 Oct. 05
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The MICE Cooling Channel
AFC Module
RF Cavity
Focusing Coil
Coupling Magnet Cryostat
Coupling Coil
Focusing Magnet Cryostat
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Half Section View of the MICECooling Channel
AFC Module
RF CavitiesAbsorber
Focusing Coil
Coupling Coil
Coupling Magnet CryostatRF Coupling Module
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MICE Focusing Magnet
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MICE: Absorber Focusing Coil (AFC) module
AFC 3D View
S/C Coil 2
Safety Window
Absorber Body
Coil Mandrel
Magnet Vacuum
Absorber Vacuum Door
Hydrogen duct
S/C Coil 1
LH2 window
Absorber vacuum
Module vacuum vessel
Cooler
AFC 2D Cross-section
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210 mm
84 mm
670 mm725 mm
235 mm
249 mm
263 mm
~450 mm
Machined 6061-T6Aluminum Forging6061 Al Cover Plate 13 mm
6.4 mm 304 St St Vessel
1 mm Cu Shield
10 mm ID He Tube
5 mm 304 St St 1 mm G-10 Insulation
~697 mm
844 mm
200 mm
12.7 mm 304 St St Module Vessel
MICE Focusing Solenoid Cross-section
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AFC Magnet Cross-section
Focusing Magnet
Cold Mass SupportMagnet Coil and Absorber Cross-section
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The Basic Parameters of the Focusing Magnet in the Non-flip and the Flip Mode
Parameter Non-flip Flip
Coil Separation (mm) 200 200
Coil Length (mm) 210 210
Coil Inner Radius (mm) 263 263
Coil Thickness (mm) 84 84
Number of Layers 76 76
No. Turns per Layer 127 127
Magnet J (A mm-2)* 71.96 138.2
Magnet Current (A)* 130.5 250.7
Magnet Self Inductance (H) 137.4 98.6
Peak Induction in Coil (T)* 5.04 7.67
Magnet Stored Energy (MJ)* 1.17 3.10
4.2 K Temp. Margin (K)* ~2.0 ~0.5
Inter-coil Z Force (MN)* -0.56 3.40
* Design based on p = 240 MeV/c and beta = 420 mm.
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10864200
100
200
300
400
T = 3.4 K
T = 4.2 K
T = 5.0 K
Focusing flip
Focusing no-flip
Induction at the Conductor (T)
Conductor Current (A)
The Focusing Magnet Load Lines and Conductor Current Versus the Magnetic Induction at Various Conductor T
TM = 2.0 K
TM = 0.5 K
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Local region applied 4.3K
T = 1.08 K
The focus magnet is attached to the cooler along a 100 mm wide strip that is at 4.3 K.
The radiation heat load on all other surfaces QR = 1.0 W m-2.
The maximum T = 1.08 K
T1T0Cooler 2nd Stage Cold HeadFlexible Copper StrapT3Vacuum VesselFocusing MagnetT2
Focusing Magnet T, Cooling along One Line
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Focusing Magnet T, Outside Cooling
The heat flux on the inner cylindrical surface and the ends is 1 W m-2; the outer cylindrical surface is at 4.3 K.
The maximumT = 0.125 K
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Magnet connection to the Cooler with a Liquid Helium Cold Pipe
PT3T2T1T0Cooler 2nd Stage Cold HeadCondensation PlateVacuum VesselLiquid Tube (any length)Gas Tube (any length)Liquid HeliumFocusing MagnetRelief ValveCryostat Neck
The superconducting coils for the MICE focus magnets will be cooled by conduction from liquid helium in a space on the outside of the magnet coils. A simple gravity feed heat pipe supplies cold liquid from the helium condenser to the bottom of the magnet. The boil off gas is re-liquefied on a condenser surface and the condense liquid helium is sent back to the bottom of the magnet helium tank
T2 - T1 < 0.1
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Focusing magnet Stress and Deflection due to the Cool Down
The results show the Von Mises Stress, Radial Deflection (negative y direction) and Longitudinal Deflection (z direction) due to cooling the Focusing Magnet Module from Room Temperature to 4.2 K.
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Focusing magnet Stress and Deflection due to the Cool Down and Magnetic Forces
The results show the von mises stress, the radial (the Y direction) and longitudinal (the Z direction) deflections, for the focusing magnet module that has been cooled from room temperature to 4.2 K, and the coils are powered for as in the baseline full-flip case with a muon beam with an average momentum of 240 MeV/c.
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MICE Coupling Magnet
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MICE: RF and Coupling module
Three quarter section 3D View of RF module
Coupling Magnet
Cavity RF Coupler
Dished Be Window
RF Cavity Cell
Module Vacuum Vessel
Vacuum Pump
Magnet Vacuum Vessel
2D view of the RF and Coupling Module
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MICE Coupling Solenoid Cross-section
30 to 40 K Shield
Cooling Tube
S/C Coil
~697 mm
Cryostat Vacuum Vessel
>1080 mm
725 mm
250 mm
386 mm
201 MHz RF Cavity
Vacuum Space
116 mm
Helium Space
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Relationship of the Coupling Coil to the Cavity
Coupling Coil
Cavity Coupler
Vacuum Pump201 MHz RF Cavity
Be Window
The coupling coil length is determined by the position of the RF couplers.
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The Basic Parameters of the Coupling Magnet in the Non-flip and the Flip Mode
Parameter Non-flip Flip
Coil Length (mm) 250 250
Coil Inner Radius (mm) 725 725
Coil Thickness (mm) 116 116
Number of Layers 104 104
No. Turns per Layer 151 151
Magnet J (A mm-2)* 104.9 115.5
Magnet Current (A)* 193.6 213.2
Magnet Self Inductance (H) 563 563
Peak Induction in Coil (T)* 7.09 7.81
Magnet Stored Energy (MJ)* 10.6 12.8
4.2 K Temp. Margin (K)* ~0.9 ~0.6
* Design based on p = 240 MeV/c and beta = 420 mm.
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The Coupling Magnet Load Lines and Conductor Current Versus the Magnetic Induction at Various Conductor T
1098765432100
100
200
300
400T = 3.4 KT = 4.2 KT = 5.0 KCoupling flipCoupling no-flip
Magnetic Induction in the Conductor (T)
Current in the Conductor (A)
TM = 0.6 K
TM = 0.9 K
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Temperature Distribution on the Coupling Coil as a Function of Cooling Location
T = 4.085 K
4.3 K
QR = 1.0 W m-2
a) Cooling at one point onthe outside surface 4.3 K
QR = 1.0 W m-2
4.568 K
T = 0.268 K
b) Cooling on the entire outside surface
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Cooler Circuit for the Coupling Magnet
The heat pipe reducesT2-T1 to < 0.1 K.
See page 23 for reductionT3-T2 within the coil.T3-T0 is ~ 0.2 K
There is no copper strapbetween the cooler and the magnet.
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Coupling Magnet Stress and Deflection due to the Cool Down and Magnetic Forces
The results show the von Mises stress, the radial (the Y direction) deflection, for the coupling magnet cooled from 300 K to 4.2 K, and the coils are powered for the full-flip case with a muon beam with a momentum of 200 MeV/c.
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Tasks Completed and Tasks to Do
Focusing Coupling
Basic Coil Design based on a Conductor Yes Yes
Temperature Distribution in Magnet Yes Yes
Stress and Deflection in Magnet Yes Yes
Cold Mass Support System Design Yes Yes
Cooler Selection and Hook Up Design Yes Yes
Quench Protection System Design Yes Dec 2004
Engineering Completed for a RFP* April 2005 June 2005
Specifications for the RFP* April 2005 June 2005
Safety Documentation for RFP* Sept. 2005 Sept. 2005
Power Supply Specification* Sept. 2005 Sept. 2005
* Based on developing a performance specification (not build to print)
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Other Magnet Related Tasks to Do
• Complete and check the cold mass support force calculations for all relevant cases. Partly Done
• Check the worst cases forces to be encountered during a magnet quench. Partly Done
• Determine if a quench of one magnet in MICE can will cause other magnets to quench inductively.
• Design the copper current leads from 300 K to 50 K for currents of 300 A and 60 A. Partly Done
• Select the 300 A and 50 A HTS leads. Partly Done
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Conclusions
• Most of the relevant design calculations have been done for the focusing and coupling magnets.
• Most of the relevant calculations have been done to allow the magnets to be cooled by small coolers.
• The 2D and 3D Drawings of the entire channel are beginning to come together.
• More work must be done a quench calculations.
• The RFP specifications for the magnets and magnet subcomponents need to be written.
• The magnets must be looked at for safety hazards.