DEVELOPMENT OF SSR2 FOCUSING LENSES FOR PIP-II … · 2019-09-11 · DEVELOPMENT OF SSR2 FOCUSING...
Transcript of DEVELOPMENT OF SSR2 FOCUSING LENSES FOR PIP-II … · 2019-09-11 · DEVELOPMENT OF SSR2 FOCUSING...
DEVELOPMENT OF SSR2 FOCUSING LENSES FOR PIP-II (Feasibility Studies for Conduction Cooled Magnet)
Electromagnetic Application Section
Electromagnetic Applications & Instrumentation Division
Team members: Kumud Singh, Janvin Itteera, Mahima, R R Singh , Rajesh Chimurkar, Rajesh Jalan & Sanjay
Malhotra
September 11, 2019 IIFC Magnet meeting presentation - Kumud Singh | SSR2 lenses For PIP-II
Vacuum pumps
Cryostat housing magnet
Electronics rack
Power diode connected in shunt with magnet
• SSR1 cryomodule Layout.
• Suggested magnet configuration inside cryomodule.
• 2D sketch of the magnet assembly.
• Conduction cooling arrangement.
• Boundary Conditions & ∆T for the cooling system for Coils
• Temperature difference in the coil winding
• Boundary Conditions & ∆T for the cooling system for current leads
• Summary
Outline
September 11, 2019 IIFC Magnet meeting presentation - Kumud Singh | SSR2 lenses For PIP-II
Vacuum pumps
Cryostat housing magnet
Electronics rack
Power diode connected in shunt with magnet
SSR1 Cryomodule Layout
SSR cryomodule cross-section –Ref [1]
Inputs from SSR cryomodule layout :
Pipe G – Diameter 6 inch
Location of 2 Phase Helium pipe –
00
Location of current leads for the
magnets – 300
Thermal Shield 50 K
September 11, 2019 IIFC Magnet meeting presentation - Kumud Singh | SSR2 lenses For PIP-II
Suggested magnet arrangement inside cryomodule
2 Phase Helium pipe
High temperature portion of current leads (copper)
Low temperature portion of current leads (HTS leads)
Coil former (Copper)
Heat Sink (Aluminium)
Conduction strips (Al foils/Copper Braids)
Inputs required:
HTS Current leads dimensions & Heat
Leak Specifications ( For testing of the
magnets at BARC SUPEROX make
HTS current leads (0.1W/pair) will be
used in test cryostat)
Radial spatial constraints around
periphery of the magnet ?
Arrangement of conduction strips from
2K pipe to coil heat sink and current
leads on one side will need to be
planned carefully.
Beam pipe (SS 316L)
Coil Conduction Plates (Azimuthal locations)
September 11, 2019 IIFC Magnet meeting presentation - Kumud Singh | SSR2 lenses For PIP-II
Cryostat housing magnet
Electronics rack
Power diode connected in shunt with magnet
2D sketch of magnet assembly
Note : Not to scale
September 11, 2019 IIFC Magnet meeting presentation - Kumud Singh | SSR2 lenses For PIP-II
Vacuum pumps
Cryostat housing magnet
Electronics rack
Power diode connected in shunt with magnet
Conduction cooling arrangement – Block diagram
Rad
iati
on
Heat
2 K pipe
Pipe/Current leads
Conduction strips
Low temperature stage for
current leads - Al Heat Sink
Conduction plates anchored to
Aluminium Heat sink
Conduction plates
(coil end)
Conduction plates
(Coil Longitudinal)
Magnet coil
Conduction strips/braids Clamped to
2K pipe
Thermal leak from the
current leads Ac losses
(Transient)
The cooling system is designed to cool the magnet via two thermal conduction passes as follows: (Pass 1): 2K pipe Cooling of SC coil (Pass 2): 2K pipe Cooling of the HTS current leads
September 11, 2019 IIFC Magnet meeting presentation - Kumud Singh | SSR2 lenses For PIP-II
Vacuum pumps Electronics rack
Power diode connected in shunt with magnet
Heat Load Calculation
AC Losses
Hysteresis Loss
𝑷𝒉𝒚 = 𝟒
𝟑𝝅 𝑱𝒄 𝒓𝒇
𝒅𝑩
𝒅𝒕𝟏 +
𝑱𝒐𝒑
𝑱𝒄
𝟐
Coupling Loss
𝑷𝒄𝒑 = 2 𝑰𝒑𝟐
𝟖 𝝅𝟐 𝝆𝒆
𝒅𝑩
𝒅𝒕
𝟐
Eddy Current Loss
Radiated heat Losses
Radiated heat from magnet
𝑸𝒓 = 𝜺 𝝈 𝑨
(𝒏+𝟏) ( 𝑻𝑯
𝟐 - 𝑻𝑳𝟐)
Losses Steady State During Ramping
AC losses 0 mW 10 mW
Radiated Heat 3 mW 3 mW
Current lead
(10 leads)
0.5W (0.1W/
Pair)
0.51W
Beam losses ? ?
Heat load on the magnet (Ball park estimates)
Filament diameter-13 μm
Ramp Rate – 20 minutes
Magnet dimensions – 250mm OD x
200 mm length
Thermal shield temperature – 50K
Magnet Temperature – 2K
Emissivity – 0.052
September 11, 2019 IIFC Magnet meeting presentation - Kumud Singh | SSR2 lenses For PIP-II
Vacuum pumps Electronics rack
Power diode connected in shunt with magnet
Boundary Conditions & ∆T for the cooling system for Coils
Parameter Value Assumptions
Conduction area (2K pipe/ Al sheet interface) 0.0191 m2 ɸ76.2 mm x 20 mm width x 4
Pipe wall thickness 1.0 mm
Thermal conductivity of the pipe wall 0.1 W/m-K @2K [3]
Resin Adhesive thickness 0.1 mm
Thermal conductivity of the resin 0.03 W/m-K @2K [3]
Conduction Area between pipe and heat sink 160 mm2 2 mm thickness x 40 mm width
Conduction plate length (2000W/m-K) 200 mm Al -5N, RRR 1000
Conduction Area of heat sink (20W/m-K) 4000 mm2 20 mm thick x 100 mm x 2
Heat sink length 200 mm Al 1050, RRR 30
Steady State
(3mW Heat load)
During Ramping
(13 mW heat load)
∆T in pipe wall 1.57 mK 6.8 mK
∆T in resin 0.52 mK 2.25 mK
September 11, 2019 IIFC Magnet meeting presentation - Kumud Singh | SSR2 lenses For PIP-II
Vacuum pumps Electronics rack
Power diode connected in shunt with magnet
Boundary Conditions & ∆T for the cooling system for Coils … continued
Parameter Value Assumptions
∆T in conduction plate 1.87 mK 8.1 mK
∆T in heat sink / superconducting coil 7.5 mK 32.5 mK
Conduction area for conduction plate on coil 240 mm2 30 mm x 2 mm width x 4
Conduction length 200 mm
Thermal conductivity of the conduction plate 1000 W/m-K @2K [3] RRR 500
Steady State During Ramping
∆T in conduction plate 2.5 mK 10.83 mK
Total ∆T 13.96 mK 60.48 mK
September 11, 2019 IIFC Magnet meeting presentation - Kumud Singh | SSR2 lenses For PIP-II
Vacuum pumps
The equivalent conductivity model
Temperature difference in the Coil winding
The coil cross-section
λ𝑐𝑜𝑖𝑙 = 𝑙𝑤 + 𝑙𝑟
𝑙𝑤λ𝑟
+ 𝑙𝑟λ𝑟
Equivalent thermal conductivity
Sr. No Parameter Value
1. Superconductor diameter 0.5 mm
2. Number of turns 8325+100+1066
3. Coil cross section 52.5mm ID 84.5
mm OD x
150mm long =
4800 mm2
4. Area ratio for
Superconductor
34%
5. Area ratio for Resin 66%
6. Thermal conductivity for
superconductor
0.3 W/m/K
7. Thermal conductivity for
resin
0.03 W/m/K
September 11, 2019 IIFC Magnet meeting presentation - Kumud Singh | SSR2 lenses For PIP-II
Vacuum pumps
Temperature difference in the Coil winding … continued
Sr. No Parameter Value
1. Conduction Area 0.054 m 2
2. Conduction Length 35 mm
3. Thermal conductivity 0.046 W/m-K
Steady State (3mW) During Ramping
(13mW)
4. ∆T in Magnet Coil 42 mK 183 mK
Total ∆T in Coil Cooling System 55.96 mK 243.48 mK
Calculated Result for temperature difference in Coil is ~0.25K
September 11, 2019 IIFC Magnet meeting presentation - Kumud Singh | SSR2 lenses For PIP-II
Vacuum pumps Electronics rack
Power diode connected in shunt with magnet
HTS current leads
Operating Current A (@ 64K)
Width Full length (mm)
HTS length (mm)
Terminal Connection holes Calculated Heat Leak 64-4.2K (pair), mW
250A 14-16 250-400 180-300 25-50 5-6.5 < 100mW
SUPEROX make HTS current lead specifications taken for calculations
September 11, 2019 IIFC Magnet meeting presentation - Kumud Singh | SSR2 lenses For PIP-II
Vacuum pumps Electronics rack
Power diode connected in shunt with magnet
Boundary Conditions & ∆T for the cooling system for current leads
Parameter Value Assumptions
Conduction area (2K pipe/ Al sheet interface) 0.0156 mm2 ɸ76.2 mm x 65 mm width x 1
Pipe wall thickness 1.0 mm
Thermal conductivity of the pipe wall 0.1 W/m-K @2K
Resin Adhesive thickness 0.1 mm
Thermal conductivity of the resin 0.03 W/m-K @2K
Conduction Area between pipe and heat sink 325 mm2 5 mm thickness x 65 mm width
Conduction plate length 300 mm
Steady State (0.5W) During Ramping(0.51W)
∆T in pipe wall 321 mK 327.42 mK
∆T in resin 107 mK 109.14 mK
∆T in conduction plate 230 mK 234.6 mK
Total ∆T 658mK 676.56 mK
Calculated Result for temperature difference in current leads is ~0.7K
September 11, 2019 IIFC Magnet meeting presentation - Kumud Singh | SSR2 lenses For PIP-II
Vacuum pumps Electronics rack
Power diode connected in shunt with magnet
Summary & Future Work
• Ball park estimates for heat load and temperature differences for magnet coil and current leads
have been calculated.
• DAE will carry out the detailed thermal analysis of the proposed magnet design.
• Recovery time after Quench of the magnet will be calculated and presented with the magnet
design.
• FNAL shall confirm the spatial constraints & current lead interface for the magnet from
cryomodule perspective.
• PDR and TRS for the magnet shall be targeted to be completed before October end. FDR
completion shall be targeted for Dec -2019 in order to close the conduction cooled magnet R&D in
next year.
September 11, 2019 IIFC Magnet meeting presentation - Kumud Singh | SSR2 lenses For PIP-II
Vacuum pumps Electronics rack
Power diode connected in shunt with magnet
References
[1] SSR1 Cryomodule, Vincent Roger, International workshop on cryomodule design and
standardization, 6th September 2018
[2] Performance of Conduction Cooled Splittable Superconducting Magnet Package for Linear
Accelerators , V. Kashikhin , N. Andreev, S. Cheban, J. DiMarco, N. Kimura, A. Makarov, Y.
Orlov, V. Poloubotko, M.Tartaglia, A.Yamamoto
[3] Superconductivity and cryogenics handbook p.1090(Japan)
[4] Feasibility studies for conduction cooled SC quadrupole for ILC cryomoudle
Thank You for your kind attention
September 11, 2019 IIFC Magnet meeting presentation - Kumud Singh | SSR2 lenses For PIP-II