Cryogenic Status of J-PARC NeutrinoSuperconducting Magnet SystemTakahiro Okamura

Table of Contents1. Purpose of this facility2. Layout of Cryogenic Components3. Conceptual Flow Diagram4. Summary of Heat LoadRefrigerator Specification

Required Cooling CapacityRequired Refrigeration Capacity

5. Operation Methods6. Test results of Heat Load7. Test results of Pressure rise at quench8. Present Status

1 Purpose

• A neutrino experiment facility usingthe J-PARC 50 GeV 0.75 kW protonbeam is now under construction atTokai campus of KEK.

• In this project, a superconductingmagnet system, which consists of 28superconducting combined-functionmagnets, will be installed in an arcsection of the primary proton beamline to bend the beam to Kamioka.

• This cryogenic facility is essential tokeep superconducting magnets below5.0 K

2. Overall Layout

+

50 G

eV M

ain R

ing

50 m

Neutrino Beam LineSuperconducting Magnets are installedin main tunnel at -12m level.Radius 105m, Length 150m

Transfer Line 100m

Power Source Control Room

Helium Refrigeratoron the ground16m×34m×8m room

Tank Yard

Co

ld B

ox

Pu

rifie

r

10m

UH1

UQ3UQ2UQ1

ST2SM1 ST1

UQ5 UH3

UH2

UQ4

ST4ST3

SM2

UD1UV2UV1

UD2

Buffer

Tank

Buffer

Tank

Eva

cu

atio

nP

um

pPower Supplies

Utilities

Ma

in C

om

pre

sso

r

Oil

Se

pa

rato

rUtilitiy Yard

Qu

en

ch

Bu

ffe

r

Qu

en

ch

Bu

ffe

rPower Utilities

Tu

be

Tra

iler

Ga

s W

arm

er

LN

2 T

an

k

!"

Main compressor(MCP)550 kWDischargE pressure:1.5 MPa

2. Layout of Cryogenic Components

LN2 > 20000 Only precooling andrecooling after quech18000 dayFor first heat exchanger(cold box)

Magnet String & Transfer LineInventory: 3900 ℓ,Cold mass: 225 ton(Fe)

3 Recovery Tanks(for Quench)Volume 100 m3×3

Cold Box SubcoolerSHE Max 300 g/s 4.5 KLHe pot : 800

Buffer Tank for Main Compressor(steady state)Volume 100m3×1

3. Conceptual Flow Diagram

Buffer

Tank

Main Compressor

LN2 CE

Sub-cooler

Beam Line Tunnel

S.C. Magnets

Subtunnel B (Connection)

!"#

Multi Transfer Line

Magn

et C

ooli

ng w

ith

Bu

s

Purifier

Radiation Shield

JT

Ma

gn

et C

oo

lin

g R

etu

rn

SHE

Pump

Currnt Leads

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 22 23 21 24 25 26 27 28

Surface

Sh

ield

Cooli

ng R

etu

rn

Sh

ield

Cooli

ng S

up

ply

Rad

uatu

i S

hie

ld

Tube Gas

Trailer

>20000 L

Turbine

100

m3

100 m3

Quench

Revcovery

Tank

Oil Separators

to Atm

End Box

Feed Box

100 m3

100 m3

Cold Box

Quench Exhausion

Vacuum

Pump

Quench Exhausion

Main compressor

First heat exchanger

Turbine

Current lead Forced flow cooling

Quench relief valves4 quench relief valves are installed

She pump made byBurber-NicholesMax mass flow rate=0.3 kg/sec

LHe potJT Valve

Transfer line

Cold box

Subcooler

Transfer line

Current lead box

Vent line lead toquench recoverytanks.

4 Refrigerator Specifications4-1. Summary of Load (Magnet & Transfer Lines) to Cryogenic System

>1.8 MPa(G)>1.8 MPa(G)Design Pressure

40 g/s, 80 K,1.35 MPa

36 kPa300 g/s, 4.5 K,400 kPa

84 kPaPressure Drop

17803900 + 10 %Contingency

1620 3550 Inventory

Aluminum basisIron basis

7.5 ton2.8 ton

Iron basis225 ton+ 10 %Contingency

Aluminum basisIron basis

6.8 ton2.5 ton

Iron basis204 tonCold Mass

1703 W403 W + 1.1 g/s+ 20 %Contingency

-7600A1.0 g/sCurrent Lead

1419 WIncluding beam lossof 150 W

336 WHeat LoadEstimation

60 100 K, 1.2 MPaHe Gas4.5 K 0.4 MPaSHECoolant

Remarks80 K LevelRemarks4.5 K Level

4 Refrigerator Specification4-2. Required Cooling Capacity

< 20 daysPre-cooling duration

Only Pre-coolingand re-cooling

after quench

LN2 usage

<6 hours (30GeVoperation)

Re-cooing duration

Not specifiedShield Cooling Gas Condition

1710 WThermal Load to Shield Line

Cold Helium GasShield Cooling

60 100 KShield Temperature

1.1 g/s (1 pair)Current Lead cooling gas

85 kPaPressure Head of SHE

410 WThermal Load to SHE Flow

4.9 KSHE Return

0.4 MPa(A), 4.5 KSHE Condition

max 300 g/sSHE Flow Rate Main Compressor

Turbine

Pump

28 S.C. Magnets

JTV

LHe

SH

E

CurrentLead

Coldbox

Schematic diagram of SHecirculation system

Efficiency Adiabatic: Density,:

Flow, Mass: Head, Pressure:

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•

# MP

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•

#=

MPPumpLoad

Expected Operational Flow Rate : 300 g/s Pump Load : < 300 W Mag. Temp. : ~ 4.8 K

2Pr

2u

D

LfessureHead

h

!=

Velocity Flow: Diameter, Hydraulic:

,: t,CoefficienFriction :

uD

LengthLf

h

]143:[

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WcoolerLoadSub

PumpLoad

TTransMag

TotalLoad

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=

Returen Temperature VS Flow Rate

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Flow Rate (kg/sec)

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ture

(K

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Thermal Load VS Flow Rate

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Flow Rate (kg/sec)

Therm

al

Load (

W)

*+,*-./01 2/20.-./01

4 Refrigerator Specification4-3. Required Cooling Capacity - Estimation

Mass-flow rate is controlled to be 0.3kg/sec at the maximum. .

2.4 kW1.2 kW+ 20 % Margine

1960 W2 kW

890 W + 1.1 g/s1.0 kW

Required Refrigeration

250 W150 WSub-cooler, Transfer Line b/wCB

330 WSHE Pump LoadContractor Design

Max 300 g/s, 4.5 K,0.4 MPaHead 85 kPa

SHE Flow conditions

1710 W410 W + 1.1 g/sMagnet & Transfer LineKEKRequirement

Thermal Load@shield Level

Thermal Load@4.5 K Level

4 Refrigerator Specification4-4. Required Refrigeration Capacity – Maker Design

Taiyo-Nissan Co. in the business collaboration with LINDE won the bid.

Buffer

Tank

Main Compressor

LN2 CE

Sub-cooler

Beam Line Tunnel

S.C. Magnets

Subtunnel B (Connection)

!"#

Multi Transfer Line

Magn

et C

ooli

ng w

ith

Bu

s

Purifier

Radiation Shield

JT

Ma

gn

et C

oo

lin

g R

etu

rn

SHE

Pump

Currnt Leads

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 22 23 21 24 25 26 27 28

Surface

Sh

ield

Cooli

ng R

etu

rn

Sh

ield

Cooli

ng S

up

ply

Rad

uatu

i S

hie

ld

Tube Gas

Trailer

>20000 L

Turbine

100

m3

100 m3

Quench

Revcovery

Tank

Oil Separators

to Atm

End Box

Feed Box

100 m3

100 m3

Cold Box

Quench Exhausion

Vacuum

Pump

Quench Exhausion

CB&SC pre-cooling

Magnet Pre-cooling

Gas Transfer

Shield Pre-cooling

5. Operation – Pre-cooling

Liquefaction

Gas Transfer

Shield Cooling

Magnet Cooling

C/L Cooling

5. Operation – Magnet Excitation (Steady state)

BufferTank

Main Compressor

LN2 CE

Sub-cooler

Beam Line Tunnel

S.C. Magnets

Subtunnel B (Connection)Multi Transfer Line

Mag

net C

oolin

g w

ith B

us

Purifier

Radiation Shield

JT

Mag

net C

oolin

g R

etur

n

SHEPump

Currnt Leads

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 22 23 21 24 25 26 27 28

Surface

Shie

ld C

oolin

g R

etur

n

Shie

ld C

oolin

g Su

pply

Rad

uatu

i Shi

eld

Tube GasTrailer

>20000 L

Turbine

100 m3

100 m3

QuenchRevcovery

Tank

Oil Separators

to Atm

End Box

Feed Box

100 m3

100 m3

Cold Box

Quench Exhausion

VacuumPump

Quench Exhausion

BufferTank

Main Compressor

LN2 CE

Sub-cooler

Beam Line Tunnel

S.C. Magnets

Subtunnel B (Connection)Multi Transfer Line

Mag

net C

oolin

g w

ith B

us

Purifier

Radiation Shield

JT

Mag

net C

oolin

g R

etur

n

SHEPump

Currnt Leads

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 22 23 21 24 25 26 27 28

Surface

Shie

ld C

oolin

g R

etur

n

Shie

ld C

oolin

g Su

pply

Rad

uatu

i Shi

eld

Tube GasTrailer

>20000 L

Turbine

100 m3

100 m3

QuenchRevcovery

Tank

Oil Separators

to Atm

End Box

Feed Box

100 m3

100 m3

Cold Box

Quench Exhausion

VacuumPump

Quench Exhausion

Liquefaction

Gas Recovery

Shield Cooling

Quench Emergent Exhaustion

C/L Cooling

Pump Protection

5. Operation - Quench

Buffer

Tank

Main Compressor

LN2 CE

Sub-cooler

Beam Line Tunnel

S.C. Magnets

Subtunnel B (Connection)

!"#

Multi Transfer Line

Magn

et C

ooli

ng w

ith

Bu

s

Purifier

Radiation Shield

JT

Ma

gn

et C

oo

lin

g R

etu

rn

SHE

Pump

Currnt Leads

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 22 23 21 24 25 26 27 28

Surface

Sh

ield

Cooli

ng R

etu

rn

Sh

ield

Cooli

ng S

up

ply

Rad

uatu

i S

hie

ld

Tube Gas

Trailer

>20000 L

Turbine

100

m3

100 m3

Quench

Revcovery

Tank

Oil Separators

to Atm

End Box

Feed Box

100 m3

100 m3

Cold Box

Quench Exhausion

Vacuum

Pump

Quench Exhausion

CB & SC Warming

Gas Recovery

Shield Warming

Magnet Warming

5. Operation - Warming

6. Two in one structure cryostat

Feed Box Mass flow rate:20 g/sec~ 40 g/secCoolant: SHETemperature 4.5Pressure :0.4 MPa

Quench protection heaterFor calibration2W, 3W, 4W

Cernox temperature censor

6. Results of Heat Load

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QPH is fired for calibration.

Pure heat load &Removed QPH Power.

Shield line forced cooling 100K 80K .

Total heat load to 4.5 K line 8.0W @Two in one structure cryostat

7. Quench simulation

This model is based on an assumption that flow is Two-dimensionalNumerical simulation is carried out involving four magnets, one relief valve, venting line andbuffer tank.

Relief Valve I.D: 25 A, L:120 mm

Emergent Exhaustion (b)

4 Magnets + Interconnect

QuenchRecovery Tank

Interconnect(a)I.D: 50AL: 770 mm

Interconnect(b)I.D: 50A, 90A,L: 1910 mm

Cryostat

Emergent Exhaustion (a)

Dirichlet TypeB.C.

25A 28.0 mm 50A 53.5 mm 90A 101.6 mm 250A 255.4 mm

7. Simulation Results at 4/4 Magnets Quench

Pressure Profile

Temperature Profile

Density Profile

SCFM SCFM SCFM SCFM

Quench relief valve Magnet(Heat Input)

Bas line

8. States

• The cold Box is being manufactured by LINDE.• The compressor is being manufactured by MYCOM.• The sub-cooler design will be finalized by TN.• SHE pump is made by Barber-Nichols.• Tank foundation design, machine room design is in progress

by KEK.• A tender for the control system is being prepared.

• Heat load to 4.5 K level of two in one structure cryostat is4.0W.

• Quench simulation involving 7 magnets is being prepared.