Cryogenics Fabrication Plans & Constraints David Montanari (on behalf of the CERN Neutrino Cryogenic Group) ProtoDUNEs Meeting Feb 23, 2016

Outline Intro Process Flow Diagram Process and Instrument Diagram Current Schedule Constraints Summary David Montanari | Cryogenics Fabrication Plans & Constraints2

Requirements (From DUNE Far Detector) Cryo-se-4: The system shall allow recirculation and purification of the liquid argon inventory to achieve the needed LAr purity to meet the scientific requirements (Less than 10 days/volume change based on ICARUS experience). Cryo-se-6: The purification system shall be capable of removing contaminants from the LAr prior to filling and shall maintain purity during operation. LArFD-L2-se-44: Electron Lifetime > 3 ms. Cryo-se-5: The system shall provide an argon gas boil off recovery and reliquefaction system. Cryo-se-16: There shall be no sources of argon gas reliquefaction inside the cryostat, e.g. un-insulated pipes carrying liquid argon. Cryo-se-25: The cryostat and cryogenic systems shall be designed for using the piston-purge technique (introducing heavy gas at the bottom and taking out exhaust from the top) for removing initial electronegative impurities. Cryo-se-8: The cryogenics system shall be designed so as not to introduce unwanted noise into the electronics. Cryo-se-10: The detector cryostat shall provide a stable liquid argon environment for the detector. Cryo-se-28: The cryostat and cryogenic systems shall be designed to maintain a single phase in the entire liquid argon volume at a stable temperature. The chosen temperature is 88.3 K +/- 1 K. Full list available on DocDB n. 112.DocDB n David Montanari | Cryogenics Fabrication Plans & Constraints3

Modes of operation 1)Piston Purge  GAr is slowly flown from the bottom of the tank to push the impurities out from the top. 2)Cool down  A mix of GAr and LAr is flown into sprayers to generate a mist of small liquid droplets that are moved around by another set of sprayers flowing GAr only. 3)Filling  Once the cryostat and TPC are cold, LAr is introduced in the cryostat. 4)Normal operations  LAr is continuously purified by means of an external LAr pump (2 are installed for redundancy, but only one is in use).  Boil-off GAr is recondensed outside of the cryostat and purified before being reintroduced as LAr. 5)Emptying  At the end of the operations (or if/when maintenance on the tank is needed), the tank is emptied and the LAr removed David Montanari | Cryogenics Fabrication Plans & Constraints4

Engineering parameters (from Detector Requirements) ModeParameterValueNotes 1 GAr purge flow rate88 m 3 /hrFrom 1.2 m/hr 2 Maximum cool-down rate TPC 40 K/hr 10 K/m 2 Maximum Delta T between any two points in the detector 50 K 2 Current cool-down rate of detector + membrane 2.5 K/hr~1 week total 3 LAr filling flow rate (*)18 l/minAssuming 2 trucks/day (**) 4 Cryostat static heat leak3.0 kWGAr boil-off (18 g/s) 4 Other heat loads (estimate)5.0 kWTotal estimate is ~ 8 kW 4 LAr circulation (5 days turnover)72 l/min (19 gpm)Nominal value (1 pump) 5 Emptying (w both LAr pumps)144 l/min (38 gpm)Limited by size of tank/truck David Montanari | Cryogenics Fabrication Plans & Constraints5 Note: Noise, micro phonics and vibrations inside the LAr volume will be studied with an external pump configuration. * Value might be limited by the pressure inside the LAr storage dewar. ** We need to contact the supplier to confirm availability of 2 trucks/day of LAr.

Cryogenic systems Internal Cryogenics:  Inside the cryostat.  GAr/LAr distribution for cryostat purge, cool down, fill. Proximity Cryogenics:  Circulate and purify LAr.  Achieve and maintain LAr purity.  Recondense and purify boil off GAr. Infrastructure/External Cryogenics:  Receive Ar/N2.  Transport GAr/LAr, GN2/LN2 to Proximity.  Vents David Montanari | Cryogenics Fabrication Plans & Constraints6

Process Flow Diagram David Montanari | Cryogenics Fabrication Plans & Constraints7 EDMS:

Current Single Phase P&ID (Sheet 1/3) David Montanari | Cryogenics Fabrication Plans & Constraints8 EDMS: Outdated: updated version being generated.

Current Single Phase P&ID (Sheet 2/3) David Montanari | Cryogenics Fabrication Plans & Constraints9 EDMS: Outdated: updated version being generated.

Current Single Phase P&ID (Sheet 3/3) David Montanari | Cryogenics Fabrication Plans & Constraints10 EDMS:

Current Status David Montanari | Cryogenics Fabrication Plans & Constraints11 We are working on P&IDs for Single Phase and Double Phase. We would like them to be as identical as possible to minimize the cost (and duration) of the design (by vendor). We are starting 3D space allocation and integration in EHN1. Next step is components sizing (pipe, vessels, valves, etc.).

Current schedule (from Fermilab LBNF/DUNE P6) David Montanari | Cryogenics Fabrication Plans & Constraints12 1)Resources not included for easier view. 2)Missing dependencies with detector and cryostat schedule (additional internal constraints). External Constraint Internal Constraint StartFinish Duration (work days)

External Constraints (external to the ProtoDUNE projects) Single tendering process for the cryogenic systems of: SBND, SBN- FD, ProtoDUNE Single Phase, ProtoDUNE Dual Phase. SBN-FD has highest priority. Finance Committee on Sep 14, 2016 (to deliver on time for detector operation before LS2).  Proposals have to be delivered to procurement by Jun 24,  The specifications need to be ready, reviewed and approved by end of April This is VERY aggressive. H2 and H4 Beams will stop in 2018 (LS2). Vendor Procurement and Fabrication duration (Estimated 1 year). If we do not allow the vendor to serialize the work (which will increase the schedule), a limited number of firms could reply to the tender David Montanari | Cryogenics Fabrication Plans & Constraints13

Internal Constraints (internal to the ProtoDUNE projects) We want to develop two systems (for the two projects SP, DP) as identical as possible. Ideally with the same P&ID and only differences in the implementation of the 3D model. The Dual Phase will be installed before the Single Phase. Side penetration installed during the installation of the membrane cryostat. Connections to the top plate only after the completion of the cryostat installation. The rest (with the exception of the side penetration) can be installed when ready. Experiments ready to run in late When installation of internal cryogenics and when detector?  Would suggest to install the internal cryogenics before the detector  it would be safer and more secure. Alternatively, there is the risk of potentially damaging the detector during piping installation (6-7 m long pieces + welding). See views in next slides David Montanari | Cryogenics Fabrication Plans & Constraints14

Internal cryogenics David Montanari | Cryogenics Fabrication Plans & Constraints15 EDMS:

Internal cryogenics – Detailed view David Montanari | Cryogenics Fabrication Plans & Constraints16 Top View Bottom view EDMS: Piping is very close to the detector.

Summary We have identified the type, size and location of the penetrations (through the cryostat top and sides) for the cryogenic services and instrumentation. We are developing the P&IDs and are starting the 3D space allocation and integration in EHN1. We have identified the spaces required inside the cryostat and in EHN1 for the installation of the cryogenic systems. Given all the constraints (external and internal to the projects), we need to proceed quickly with the design of the cryogenic systems to meet the schedule of the Finance Committee (and tender) and fabrication and installation on time for operation in late This is very aggressive David Montanari | Cryogenics Fabrication Plans & Constraints17

Thanks David Montanari | Cryogenics Fabrication Plans & Constraints18

List of available documents P&ID and PFD:  EDMS EDMS D model and drawings:  EDMS EDMS LAr filtration information:  EDMS EDMS Cryo-Piping design:  EDMS EDMS GAr purge CFD Simulations:  DUNE DocDB n. 903.DocDB n. 903 LAr cool down CFD Simulations:  DUNE DocDB n. 866.DocDB n. 866 This presentation:  EDMS EDMS David Montanari | Cryogenics Fabrication Plans & Constraints19

Cryostat with pump towers David Montanari | Cryogenics Fabrication Plans & Constraints20 EDMS: pumps for redundancy. Only 1 running during normal ops.