1. The HiLumi LHC Design Study (a sub-system of HL-LHC) is co-funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404. Cryogenics for HL-LHC Laurent Tavian, Cryogenic Group, Technology Department, CERN With the contribution of K. Brodzinski, G. Ferlin, U. Wagner & R. van Weelderen 3 rd Joint HiLumi, LHC-LARP Annual Meeting 11-15 November 2013, Daresbury Laboratory

2. Content Overall HL-LHC cryogenic layout Overall HL-LHC cryogenic layout Beam parameter & heat loads Beam parameter & heat loads HL-LHC and Sector cryoplants HL-LHC and Sector cryoplants Cryogenic layout proposals at: Cryogenic layout proposals at: Points 1, 2, 5 and 7 for cryo-collimators Points 1, 2, 5 and 7 for cryo-collimators Point 7 for SC links Point 7 for SC links Point 4 for RF insertion Point 4 for RF insertion Point 1 and Point 5 for new high-luminosity insertions Point 1 and Point 5 for new high-luminosity insertions Rough estimate of buildings and utilities requirements Rough estimate of buildings and utilities requirements Schedule, organization and conclusion Schedule, organization and conclusion

3. Overall HL-LHC cryogenic layout HL-LHC cryo-upgrade: HL-LHC cryo-upgrade: 2 new cryoplants at P1 and P5 for high luminosity insertions 2 new cryoplants at P1 and P5 for high luminosity insertions 1 new cryoplant at P4 for SRF cryomodules 1 new cryoplant at P4 for SRF cryomodules New cooling circuits at P7 for SC links and deported current feed boxes New cooling circuits at P7 for SC links and deported current feed boxes Cryogenic design support for cryo- collimators and 11 T dipoles at P1, P3, P5 and P7 Cryogenic design support for cryo- collimators and 11 T dipoles at P1, P3, P5 and P7

4. Beam parameters (impacting cryo) for HL-LHC ParametersNominalHL-LHC Beam energy, E[TeV]77 Bunch population, Nb[# p / bunch]1.15E+112.2E+11 Number of bunches, nb[-]28082760 Luminosity P1 and P5, L[Hz/cm 2 ]1E+345E+34 Bunch length, σ[ns]11 x ~2 x 5

5. Heat loads To be validated by the Heat Load Working Group!

6. Sector cryoplants With successful dipole scrubbing (e-cloud only in quadrupoles) With e-cloud in dipoles and quadrupoles  The main concerns (showstopper!) Cold masses Current leads Thermal shields Beam screens

7. Cryo-collimators at Pt1, Pt2, Pt5 and Pt7 Cryogenics design support : Main cryogenics constraints: Continuity of the cell cooling (bayonet HX, free section of pressurized HeII), hydraulic impedance for cool-down, warm-up and quench discharge… Good progress in collaboration with WP5 and WP11

8. New SC links at P7 Cryogenics design support: Optimisation of the SC link cooling taking into account fixed boundary conditions imposed by the existing cryogenic distribution scheme (QRL headers P, T…) In progress in collaboration with WP6

9. Upgrade of the RF insertion Cryogenics design support for: New 800 MHz (200 MHz?) cavity module New electron lenses Just started in collaboration with WP4 and WP5

10. New cryogenic infrastructure at P4 -1 warm compressor station (WCS) in noise insulated surface building -1 lower cold box (LCB) in UX45 cavern -1 valve box in UX45 cavern -2 main cryogenic distribution lines -2 interconnection lines with existing QRL service modules QRL

11. P4 cryogenic process & flow diagram New refrigerator cold box UX45

12. Size of new RF cryoplant (provisional) Temperature levelStaticDynamicInstalled Equivalent installed capacity @ 4.5 K [kW] 4.5 K[W]1344173651325.5 5.7 50-75 K[W]1000022500.2 Uncertainty coefficient, fu: 1.25 for existing component (400 MHz RF module) 1.5 for new equipment Overcapacity coefficient, fo: 1.5 (Qsta*fu + Qdyn)*fo To be validated by the Heat Load Working Group!

13. Upgrade of the P1 & P5 insertions Cryogenics design support for new cryo-assemblies (CC, IT & MS cryomagnets, DFBs, SC links…) In progress in collaboration with WP3 and WP4 Well advanced for magnet cooling Under investigation for CC and BS cooling 2 modules of 4 cavities Arc current feed boxes remain in the tunnel

14. New cryogenic infrastructure at P1 and P5 -1 warm compressor station (WCS) in noise insulated surface building -1 upper cold box (UCB) in surface building -1 cold quench buffer (QV) in surface -1 or 2 cold compressor boxes (CCB) in underground cavern -2 main cryogenic distribution lines -2 interconnection valve boxes with existing QRL Critical integration issue

15. Size of new IT cryoplants (provisional) Temperature levelStaticDynamicInstalled Equivalent installed capacity @ 4.5 K [kW] 1.9 K[W]4331380304512 18 4.5 K[W]19684520.5 4.6-20 K[W]154259842432.4 50-75 K[W]4900073500.5 20-300 K[g/s]16 592.6 Uncertainty coefficient, fu: 1.5 Overcapacity coefficient, fo: 1.5 (Qsta*fu + Qdyn)*fo To be validated by the Heat Load Working Group! What about possible redundancy with detector cryogenic plants? (~1.5 kW @ 4.5 K for CMS) (~3 kW @ 4.5 K for ATLAS) Current lead cooling “à la LHC” to be reviewed with WP6 !

16. Number of cold compressor trains LHC sector Present HL-LHC

17. Minimum CCB requirement in cavern Depending of the total cooling capacity and operating temperature Single CC trainDouble CC train Best for cavern integration Global or distributed ? (500 W max size for distributed HX !) 500 W HX 2.2 K, 1.3 bar 1.8 K, 16 mbar 4.6 K, 3 bar 20 K, 1.3 bar 50 K, 20 bar 75 K, 19 bar

18. Building and general service requirements Cryogenic systemP1 and P5P4 Warm compressor building Surface[m2]700500 Crane[t]20 Electrical power[MW]4.62.0 Cooling water[m3/h]540227 Compressed air[Nm3/h]3020 Ventilation[kW]250100 Type[-]Noise-insulated (~108 dB_A) Surface "SD" building Surface[mxm]30x10N/A Height[m]12N/A Crane[t]5N/A Electrical power[kW]50N/A Cooling water[m3/h]15N/A Compressed air[Nm3/h]90N/A Cavern Volume[m3]200300 Local handling[t]22 Electrical power[kW]10020 Cooling water[m3/h]20 Compressed air[Nm3/h]4030 Provisional! (+ access areas)

19. Schedule : Freeze of heat load requirement P7 P1&P5

20. WP9-Cryogenics organization chart

21. Conclusion Main contributions to other WPs: the cooling studies of cryogenic assemblies have started: Main contributions to other WPs: the cooling studies of cryogenic assemblies have started: Cooling studies of new magnet cold masses are well advanced Cooling studies of new magnet cold masses are well advanced Cooling studies of inner triplet beam screens have started an are challenging (12-22 W/m!) Cooling studies of inner triplet beam screens have started an are challenging (12-22 W/m!) Cooling studies for crab-cavities, cold powering and cryo- collimators follow the development. Cooling studies for crab-cavities, cold powering and cryo- collimators follow the development. Test stations for SC link operational, for CC under commissioning Test stations for SC link operational, for CC under commissioning Corresponding cryogenic infrastructure are under definition Corresponding cryogenic infrastructure are under definition The integration of cavern equipment (cold-compressor box(es)) at P1 and P5 remains a concern. The integration of cavern equipment (cold-compressor box(es)) at P1 and P5 remains a concern. The size of the cryoplants remains compatible with the pre-design data (OK with CtC) if the scrubbing of the beam screens is effective (at least for dipole magnets). The size of the cryoplants remains compatible with the pre-design data (OK with CtC) if the scrubbing of the beam screens is effective (at least for dipole magnets).