cryogenics at cern · 2018. 11. 18. · lhc proton-proton collider @ 14 tev. european graduate...

1 D.D. / 1st of September 2010European Graduate Course in Cryogenics 2010, Helium Week, CERN, Geneva, Switzerland

1

European Graduate Course in Cryogenics 2010 Helium Week, CERN, Geneva, Switzerland

Cryogenics at CERN

D. Delikaris, on behalf of theCryogenics Group, Technology Department, CERN


2

Agenda

Brief introduction to CERNCryogenics at CERN

» LHC collider (accelerator and detectors)» Fixed target detectors» Test bench facilities and general services» Cryogen management & distribution» Cryogenics operation; present status

Conclusions

D.D. / 1st of September 2010European Graduate Course in Cryogenics 2010, Helium Week, CERN, Geneva, Switzerland

3

CERN, European Organization for Nuclear ResearchAn Intergovernmental Organisation for the High Energy Physics Research

The LHC project (accelerator & detectors)


4

CERN, European Organization for Nuclear ResearchAn Intergovernmental Organisation for the High Energy Physics Research

Several (main) questions:

Origin of the mass? Coupling with Higgs field via Higgs boson?

Matter / antimatter asymmetry?

Origin of the dark energy / matter?

Forces unification (single model?)

Instrument - Observable: Accelerators/colliders - (mass energy):

Allowing Universe expansion

Gravitational observationbut not detected

5

CERN accelerator complex


LHC proton-proton collider @ 14 TeV


6

Cryogenics at CERN; Main users (1/2)

LHC helium refrigeration systems

LHC accelerator:Cooling at 1.9 K of superconducting magnets (37’000 t of cold mass) distributed over the 26.7 km underground accelerator

LHC physics detectors:ATLAS, cooling at 4.5 K of toroidalsuperconducting magnetic system & central solenoid (1275 t of cold mass)CMS, superconducting solenoid (225 t of cold mass)

First events from the LHC @ 7 TeV


7

Cryogenics at CERN; Main users (2/2)

CERN wide helium refrigeration systems

Several helium cryogenic plants are in continuous operation supplying refrigeration capacity for:

Large superconducting magnetic spectrometers for fixed target physics detectors (on beam or standalone)

Cryogenic test benches of superconducting accelerator magnets, cables, wires, cavities (scheduled visit Wed. 1st of September)

LHC detector components tests (magnets and sub-detectors)

Cryogenic laboratory test bench facilities (scheduled course Thu. 2nd of September)

In situ helium liquefaction & distribution for users without dedicated cryogenic system


8

Evolution of the helium cryogenic power at CERN

0

20

40

60

80

100

120

140

160

180

1960 1970 1980 1990 2000

Year

kW @

4.5

K

OMEGA, BEBCISR Low-Beta

ALEPH, DELPHI,LEP Low-Beta

LEP2

LHC, ATLAS, CMS

LEP2+

LHC

Increase of the heliumrefrigeration capacity at CERN for accelerators,detectors & test benchfacilities (leading to updatedconditions and infrastructure forcryogen procurement and storage(helium and nitrogen)

9European Graduate Course in Cryogenics 2010, Helium Week, CERN, Geneva, Switzerland

9

Footprint of cryogenic plant

D.D. / 1st of September 2010

LHC accelerator

LHC detectors

Other detectors

Test areas

Central services

Standby

Cryogenic installations location

10

Overall refrigeration capacity


10

Temperature Overall installed capacity LHC Non-LHC

Number of

plantsLHC Non-

LHC

80 K 5.2 MW 5 MW 0.2 MW 13 11 2

20 K 60 W - 60 W 2 - 2

4.5 K 163.6 kW 151.5 kW 12.1 kW 23 10 13

1.8 K 19.65 kW 19.2 kW 0.45 W 12 8 4

300 mK 350 mW - 350 mW 1 - 1

Totals 51 29 22

Plants & ancillary equipment to be operated with respect to CERN’s scientific program

Refrigeration capacity at CERN

11

Refrigeration capacity @ CERN


11

1E‐01

1E+00

1E+01

1E+02

1E+03

1E+04

1E+05

1E+06

S1‐2

S2‐3

S3‐4

S4‐5

S5‐6

S6‐7

S7‐8

S8‐1

ATLAS magnets

ATLAS Shields

ATLAS Calorimeter

CMS

CAST

Fix target

Compass magnet

Compass detector

Compass fix target

NA62

NA62

NA62

Kr calorimeter

Bloc 4

ATLAS H8

CMS H2

B163

SM18

Main

SM18

CWU

SM18

CCU

Central liquefier

Cryogenic labo

ratory

West A

rea

Ex‐ALEPH

Coldex

LHC LHC detectors

Other dectors Teat areas and services Stand‐by

Refrigeration

capa

city [W

]

80 K

20 K

4.5 K

1.8 K

300 mK

Refrigeration capacity per user at CERN

12

LHC accelerator in the tunnel


12

36’000 t of cold mass (1232 dipoles, 474 quadrupoles &7612 correctors superconducting magnets) distributed over 26.7 km of the underground accelerator to be cooled at 1.9 K

The LHC accelerator cryogenics; General


13

LHC accelerator cooling down history

LHC Temperature evolution

0

50

100

150

200

250

300

01-Jan-2007

02-Apr-2007

02-Jul-

2007

01-Oct-2007

31-Dec-2007

31-Mar-2008

30-Jun-2008

29-Sep-2008

29-Dec-2008

30-Mar-2009

29-Jun-2009

28-Sep-2009

28-Dec-2009

29-Mar-2010

Tem

per

ature

[K]

ARC12_MAGS_TTAVG ARC23_MAGS_TTAVG ARC34_MAGS_TTAVG ARC45_MAGS_TTAVGARC56_MAGS_TTAVG ARC67_MAGS_TTAVG ARC78_MAGS_TTAVG ARC81_MAGS_TTAVG


14

The LHC accelerator cryogenics; Layout

8 x 18 kW @ 4.5 K

8 x 2.4 kW @ 1.8 K

36’000 t @ 1.9K

130 t helium inventory

(80t of He II)

(Distribution line)(Interconnection box)

Cryogenic plant 5 cryogenic “islands”P1.8, P2, P4, P6, P8

Visit organised for Wed. 1st of September!


15

1

10

100

1000

10000

1 10

T [K]

P [k

Pa]

SOLID

HeII HeI

CRITICAL POINT

GAS

λ line

Saturated He II

Pressurized He II

1

10

100

1000

10000

1 10

T [K]

P [k

Pa]

SOLID

HeII HeI

CRITICAL POINT

GAS

λ line

Saturated He II

Pressurized He II

The LHC accelerator cryogenics; The Helium II cooling principle

D.D. / 1st of September 2010European Graduate Course in Cryogenics 2010, Helium Week, CERN Geneva Switzerland

16

UpperCold Box

Interconnection Box

Cold Box

WarmCompressor

Station

LowerCold Box

Distribution Line Distribution Line

Magnet Cryostats, DFB, ACS Magnet Cryostats, DFB, ACS

ColdCompressor

box

Shaf

tSu

rface

Cav

ern

Tunn

el

LHC Sector (3.3 km) LHC Sector (3.3 km)

1.8 KRefrigeration

Unit

New4.5 K

Refrigerator

Existing4.5 K

Refrigerator

1.8 KRefrigeration

UnitWarm

CompressorStation

WarmCompressor

Station

WarmCompressor

Station

ColdCompressor

box

Even pointOdd point Odd point

MP StorageMP Storage MP Storage

UpperCold Box

Interconnection Box

Cold Box

WarmCompressor

Station

LowerCold Box



ColdCompressor

box

UpperCold Box

Interconnection Box

Cold Box

WarmCompressor

Station

LowerCold Box



ColdCompressor

box

Shaf

tSu

rface

Cav

ern

Tunn

el


1.8 KRefrigeration

Unit

New4.5 K

Refrigerator

Existing4.5 K

Refrigerator

1.8 KRefrigeration

UnitWarm

CompressorStation

WarmCompressor

Station

WarmCompressor

Station

ColdCompressor

box



UpperCold Box

Interconnection Box

Cold Box

WarmCompressor

Station

LowerCold Box



ColdCompressor

box

UpperCold Box

Cold Box

WarmCompressor

Station

LowerCold Box


ColdCompressor

box

Shaf

tSu

rface

Cav

ern

Tunn

el


1.8 KRefrigeration

Unit

New4.5 K

Refrigerator

Existing4.5 K

Refrigerator

1.8 KRefrigeration

UnitWarm

CompressorStation

WarmCompressor

Station

WarmCompressor

Station

ColdCompressor

box



UpperCold Box

Interconnection Box

Cold Box

WarmCompressor

Station

LowerCold Box



ColdCompressor

box

The LHC accelerator cryogenics; typical cryogenic “island”

17

LHC Accelerator Cryogenics


17

8 x 18 kW @ 4.5 K units

TypicalHelium Compressors station

&Cold Boxes

The LHC accelerator cryogenics; 4.5 K units

18



18

IHI- Linde Air Liquide8 x 2.4 kW @ 1.8 K units

Warm Compressors &Cold Boxes


19



19

LHC Cold Compressors (speed range 100 – 800 Hz)

IHI-Linde Air Liquide


20

ATLAS & CMS LHC Detectors


20

ATLAS, cooling at 4.5 K of a toroid superconducting magnetic system and central solenoid (1’275 t of cold mass)

ATLAS, liquid argon (83’000 liters) calorimeter system (660 t cold mass)

CMS, cooling at 4.5 K of a superconducting solenoid (225 t of cold mass)

The LHC detectors cryogenics; General


21

HELIUM1 central superconducting solenoid; 5.3 m

length, 2.4 m inner diameter, 2 T; cooled by thermo-siphon effect;

8 super-conducting toroid magnets cooled by saturated He flow forced by centrifugal pumps (1200 g/s); one barrel and two end caps; 26 m length, 20 m external diameter; 1.8 GJ stored energy

LIQUID ARGONOne calorimeter detector (subdivided in a barrel

and two end caps) using Liquid Argon as ionization mean; 13 m length , 9 m external diameter, 45 m3 + 2x19 m3 = 83 m3 of LAr

Operating temperature at 87 K in sub-cooled condition preventing bubble formation

Cooled by a two phase flow of LN2 forced by centrifugal pumps

The LHC detectors cryogenics; ATLAS

Liquid Argon CalorimeterTemperature uniformity < 0.3 KTemperature stability < 0.02 K


22

The LHC detectors cryogenics; ATLAS Helium Cryogenics architecture

Coo

ldow

n &

shie

ldre

frige

rato

r

Distribution valve box

Centrifugalpump

ATLASSolenoid

Pro

xim

ity C

ryog

enic

Syst

em (P

CS

)

ATLA

S ca

vern

s

4.5

K re

frige

rato

r

Phaseseparator

ATLAS Toroid

End

cap

Bar

rel

End

cap

Surfa

ceHe Main Refrigerator:

6 kW @ 4.5 K

He Shield Refrigerator:20 kW 40 - 80 K60 kW 300 - 100 K

PCS Valve boxand Phase Separator Centrifugal pump

(1200 g/s of LHe)

23

ATLAS Detector Cryogenics (LHC)


23

The LHC detectors cryogenics; ATLAS Liquid Argon Cryogenics architecture

20kW@84KN2 refrigerator

2x50m3 LAr storage tanks

2x50m3 LN2 storage tanks 1x80m3 GN2 Buffer

15m3 N2 phase separator dewar


24

The LHC detectors cryogenics; CMS

Large superconducting solenoid: 13 m length, 5.6 m inner diameter, 4 T, 2.6 GJ of stored energyIndirectly cooled at 4.5 K by thermo-siphon

effect


25

4.5 K refrigerator

6000 l LHe dewar(back-up system)

Phaseseparator

CMS Solenoid

Pro

xim

ity C

ryog

enic

Sys

tem

(PC

S)

CM

S c

aver

nsS

urfa

ce

The LHC detectors cryogenics; CMS Helium Cryogenics architecture

1.5 kW @ 4.5 K unit

He Compressors Hall

Phase separator &6’000 l LHe dewar

Cold box arrival at surface test location

26

NA58 Compass Detector (SPS)

D.D. / 1st of September 2010 European Graduate Course in Cryogenics 2010, Helium Week, CERN, Geneva, Switzerland

26

The COMPASSmagnet & dilution Refrigerator

Cryogenic units:

400 W @ 4.5 K&350 mW @ 300 mK

Cryogenics for fixed target detectors; COMPASS detector (SPS)

27

NA61, NA62 Detectors (SPS)

European Graduate Course in Cryogenics 2010, Helium Week, CERN, Geneva, Switzerland

27 D.D. / 1st of September 2010

NA62: Liquid Krypton calorimeter(10’000 liters)

NA61 2 cryogenic units of 400 W @ 4.5 K2 spectrometer magnets

Cryogenics for fixed target detectors; NA61 & NA62 detectors (SPS)

28

CAST Detector


28

CERN Axion Solar TelescopeCryogenic unit:800 W @ 4.5 K

Cryogenics for fixed target detectors; CAST detectors (sun particle flux)

29

Test Facilities for ATLAS & CMS (SPS)


29

CMS RD5 H2 beam, Cryogenic unit400 W @ 4.5 K

ATLAS H8 beam, Cryogenic unit

400 W @ 4.5 K

Cryogenics for fixed target detectors; Test facilities for ATLAS & CMS (SPS)

30

Test facilities & general services

European Graduate Course in Cryogenics 2010, Helium Week, CERN, Geneva, Switzerland

30 D.D. / 1st of September 2010

…auxiliary superconductingmagnets

Cryogenic unit:400 W @ 4.5 K


Cryogenic test benches for wires, cables and…

Cryogenics for test bench facilities; Superconducting cables, wires and magnets

31

SM18 Test benches (LHC magnets)


31


12 cryogenic test benches for the LHC superconducting magnets nominally tested before underground installation (several years of 24h/24, 7d/7 cryogenic operation)

Originally: tests performed with one 18 kW@ 4.5 K unit from LHC

Presently: tests performed with one cryogenic unit of 6 kW @ 4.5 K

Cryogenics for test bench facilities for superconducting magnets, cavities


32



32

Central liquid helium production in situ and distribution by means of mobile containers(from 100 to 2000 liters)of up to 250’000 liters per year, CERN wide


(R&D programs, accelerators & physics detectors without dedicated helium cryogenic plant)

Cryogenics for Central Liquefier general services

33

CERN wide cryogenic support for testing and validating technical solutions

Operation and development of special laboratory measuring equipment for CERN users.

Consultancy for scientific, technical studies and development for cryogenic engineering

D.D. / 1st of September 2010 European Graduate Course in Cryogenics 2010, Helium Week, CERN, Geneva, Switzerland

Cryogenic Laboratory (Cryolab)

Course scheduled for Thu. 2nd of September!

34

Cryogen storage and distribution


Cryogen management & storage

Helium & Liquid nitrogen Inventory

Present total helium inventory at CERN: 160’000 kgLHC (accelerator & detectors) helium full inventory: 136’000 kgLHC accelerator storage capacity: 75’000 kg in situ, 55’000 kg of “virtual storage” in collaboration with industrial suppliers; infrastructure update for a full storage capacity in situ is ongoing

LHC (accelerator & detectors) liquid nitrogen needs for a full cool down: 11’500 ton(LHC accelerator full cool down: 10’000 ton in 33 continuous days; equivalent to 500 standard transportable containers delivered byindustrial suppliers)

In situ helium liquefaction for central services (up to 250’000 liter per year) and distribution by means of mobile containers ranging from 100 to 2’000 liter (users without dedicated cryogenic plant)

35

Cryogen storage and distributionStorage infrastructure (in brackets: capacity dedicated to LHC)


Gas & liquid helium storage capacity at CERN

Liquid nitrogen storage capacity at CERN

Gas tank capacity [m3] 250 (at 2.1 MPa) 80 (at 1.5 & 2.1 MPa)

Number of units at CERN 58 (58) 65 (40)

Liquid tank capacity [liter] 120’000(fixed)

25’000(fixed)

11’000(mobile)

6’000(fixed)

Number of units 2 (2)* 1 2 1

Container capacity [liter] 50’000 40’000 27’000 20’000 15’000 10’000 6’000Number of units 14 (13) 2 1 2 2 1 7

*6 (6) by end of 2010



LHC helium storage & Distribution (high grade helium ring line, 2 MPa, 27 km long, for LHC operation)

[Completing the existing CERN helium recovery system: high grade, 20 MPa, 5 km long and low grade, 3 kPa & 20 MPa, 3 km long each]



37



Cryogen management & storage (Nitrogen)

38



Cryogen management & storage (Helium)

39

Cryogenics operation methodology

Cryogenics operation at CERN (2010):

48 out of the 51 cryogenic plants & ancillary equipments in operation or active stand by (may be used on request)All LHC (accelerator & detectors) cryogenic plants in full operationAll fixed target cryogenic plants in full operability with respect to the scientific program & beam availabilityAll test facilities cryogenic plants in full operationOnly 3 helium cryogenic plants are in long term stand by (not immediately operational)

Approximately 85 persons from CERN & contractual Industrial Support staff are participating to the Operation, Maintenance, Technical Support and Consolidation tasks of the cryogenic systems at CERN


Cryogenics operation; present status

40

ConclusionsCryogenics at CERN: since 1960’s for cooling components on accelerators, physics detectors & test facilitiesVery large spectrum of cryogenic engineering & working conditions (applications and refrigeration capacity @ T K)Implementation & successful operation of “state of the art”industrial cryogenic equipment at the edge of the present technology: The LHC cryogenic system is the largest, the longest and the most complex cryogenic system worldwide (26.7 km, cooling @1.8 K, 80 ton of He II)Procurement and management of very important cryogen inventory (helium and nitrogen)Cryogenic operation availability to the users:Before the LHC era: nearly 590’000 running hours have been cumulated over 15 years with a mean availability rate of 99%The present LHC mean availability is already situated at 90%; progress is very impressive! Peaks at 99% are observed for several week periods!


Conclusions

cryogenics at cern · 2018. 11. 18. · lhc proton-proton collider @ 14 tev. european graduate...

Documents