dune integration meeting apa test facility (apatf ... · • contamination of ln2 source is...

DUNE Integration Meeting

APA Test Facility (APATF)Cryogenic System Design Status

Andrew Dalesandro, Erik Voirin, David Montanari, Terry Tope19 June 2019

Agenda

• Functional Requirements • Additional Considerations and Assumptions• APATF Cryogenic System P&ID• Cryogenic System Design Overview• LN2 Consumption• Temperature Profile and Uniformity• Operating Modes• Refrigeration• Logistics• Cryogenic System Footprint• Pressure Safety and Reliefs

19 June 2019Andrew Dalesandro | DUNE APATF – Cryogenic System2

Abbreviations


Acronym Description

APA Anode Panel Array

APATF APA Test Facility

CBX Coldbox; for testing APAs

CS Cryogenic System; refrigeration & cryogenic distribution for the APATF

DUNE Deep Underground Neutrino Experiment

FEA Finite Element Analysis

LBNF Long Baseline Neutrino Facility

MAWP Maximum Allowable Working Pressure

ODH Oxygen Deficiency Hazard

SF Safety Factor

Functional Requirements1

• Three Coldboxes (CBX) testing dual APAs, operating in parallel– Cool down: 24 hrs, 290 K à ~ 90 K

• Only one CBX cool down at a time• Cool down of one CBX must not effect operation of other two• 1600 kg of dual APA thermal mass, predominantly 300 series SS

– Steady-state operations: 48 hrs, ~ 90 K• All three CBX operate simultaneously

– Warm up: 24 hrs, ~ 90 K à 290 K• All three CBX warm up simultaneously

• Steady-state operating parameters– Nominally 90 K, > 1 bara à dry nitrogen vapor flow– +60 K / -0 K temperature uniformity– No moisture present, nitrogen purity TBD– 300 W of electronics load per CBX

• CBX dimensions à 3 x 1.2 x 13.5 m internal, 4 x 2.2 x 14.5 m external– CBX design/delivery is not within Cryogenic System scope

• CS designed for programmable remote operations, 10 years continuous operating lifetime• CS components and nitrogen vessels will have space provided in proximity to CBX• ODH System is not within CS scope• Transporting components underground is limited by shaft elevator

– Max component dimensions à 1.38 x 3.6 x 3.69 m– Maximum component mass à 5900 kg


1: Functional Requirements for DUNE Cold Box and Cryogenic System – Underground APA Integrated Testing, Rev 8, 18 Jan 2019, F. Feyzi, D. Montanari.

Additional Considerations and Assumptions• APATF CS installed within DUNE cleanroom; should not interrupt cleanroom ops• CS supplies refrigeration to APATF within each detector cleanroom

– Cryo components should be portable whenever practical• DUNE Cryogenic System surface LN2 storage vessel cannot flow directly to APATF

– APATF CS refrigeration must be sourced underground– APATF CS piping will be vacuum insulated to limit losses

• CBX insulation is ~ 300 mm thick foam, similar to ProtoDUNE APA test insulation• Cryogenic penetrations are all located on top of each CBX• Temperature sensors cannot be mounted to APAs à measure N2 gas temperature only• CBX design does not include a metal membrane vapor barrier between APA and

insulation• LN2 dewar transport on Ross Shaft elevator requires min 17 minutes roundtrip,

including load and unload• APATF cryo system available footprint: 12 m x 5 m = 60 m2 on top of each Detector;

Height restricted to ≤ 2.5 m• CBX MAWP ≤ 160 mbarg; Operating pressure ≤ 100 mbarg• Spacing between CBX ≥ 30 mm• CBX vents into the common exhaust duct manifold, ~ 60 m vent header• DUNE Cavern primary ventilation inlet has zero back pressure on CBX venting flow• Contamination of LN2 source is anticipated as ≤ 5 ppm H2O• Expectation is for 1 zero-APA commissioning test per CBX


APATF Cryogenic System PID


Cryogenic System Design Overview

• 11000 L LN2 storage vessel, buffer supply volume• 2000 L LN2 transport dewar• Purge: Gas sprayers at bottom of CBX, symmetric on each side of APA à

4 hrs: 4 vol changes, 1 vol change/hr– Dewpoint + moisture analyzer on vent to monitor H2O contamination

• Cool-down: Liquid sprayers at top of CBX, symmetric on each side of APA à 24 hrs– Finned cold trap before sprayers to freeze out residual contamination

• Cold Testing: Liquid Sprayers at top of CBX à 48 hrs– Cold Trap doubles as baffle to prevent LN2 spray directly on APAs

• Bypass valve allows flow control to balance orifice pre-cooling• Warm-up: CBX internal heaters + gas sprayers as needed à 20 hrs• Vent: Low pressure exhaust to Cavern common ventilation

– Heater on vent line to warm exhaust gas– Flow meter to monitor N2 flow rate + consumption rate– Check valve to mitigate contamination back flow migration


APATF LN2 Consumption

• All operating modes utilize N2 from storage dewar• ~ 2970 kg LN2 per thermal cycle:

• With +50% margin added, saturated LN2 consumption:– ~ 5500 L / CBX thermal cycle– ~ 4100 L / day with 3 CBX operating cold


LN2 Usage @ Temp234.4 @ 50F

1013.1 Liquid

1579.9 Liquid

144.0 @ 295K

2971.5

Time Flow RateMode of Operation:Purge: kg in 4 hours 16.3 gm/sec

variable 6-16.7 gm/sec

9.14 gm/sec

Warmup kg in 20 hours low, 2 gm/sec?

Cooldown LN2 Usage:

Testing LN2 Usage

Total:

kg in 24 hours

kg in 48 hours

kg in 96 hours

Description Value UnitsLN2 consumption per CBX per thermal cycle 2,972 kg/CBXLN2 saturated density 808 kg/m^3LN2 consumption per CBX per thermal cycle 3,679 L/CBXExtra Margin, SF 50 %Total LN2 consumption per thermal cycle per CBX 5,519 L/CBX/testTest duration of one dual APA 4 daysLN2 consumption per CBX per day during operations 1,380 L/CBx/dayTotal LN2 consumption per day during ops for 3 CBX 4,139 L/day

Temperature Profile and Uniformity• APA CBX Temperature Profile

– Temperature profile of all internal CBX components over full thermal cycle

– Overshoot warm-up of CBX N2 gas temp ≥ 316 K à maintain all temperatures > 282 K dewpoint after 18 hr warm-up

– Add 2 hr waiting period to help temps normalize

– 20 hr total warmup– Bottom electronics temperature lag +

offset


APA CBX Temperature Uniformity

APA CBX Temperature Profile

• APA CBX Temperature Uniformity– Component temperature – N2 average gas

temperature over full thermal cycle– APA CBX ΔT max ≤ 50 K

Mechanical Refrigeration Supply

• Primary source of refrigeration is mechanical LN2 liquefier installed on the Detector Mezzanine

• Most practical solution is a PSA Liquefier – PSA generates its own purified N2 from utility compressed air

• N2 stock gas inventory not required– Pure N2 then injected to standard liquefier unit

• 13 kW, (290 L/hr) at ~ 80 K, 300 mbarg• 290 L/hr == 6960 L/day

– Liquefier overcapacity can be stored in 11k L storage dewar• Working w/ multiple vendors to assess commercial availability

– Stirling, Cosmodyne à proposals received– Air Products à meeting scheduled 20 June to discuss options


LN2 Transport Dewar Supply• Contingent refrigeration is a portable LN2 transport dewar

– 2000 L capacity and fits on Ross Shaft elevator– Round trip ~ 4 hrs to fill/empty/re-fill; delays not accounted for

• ~ 4 fills per CBX test• ~ 3 fills per day when all 3 CBX running• 1200 labor hours per Detector (75 dual-APA tests)


Task Description Total Labor [hr]Connect LNTD to surface dewar 0.08 Fill LNTD from surface dewar 0.75 Disconnect LNTD from surface dewar 0.17 Move LNTD from surface dewar to top of elevator shaft 0.25 Load LNTD onto elevator 0.08 Descend LNTD from surface to cavern 0.07 Unload LNTD from elevator 0.08 Move LNTD from cavern elevator to DUNE mezzanine 0.50 Move LNTD from mezzanine drop point to CryoSys storage dewar 0.17 Connect LNTD to CryoSys storage dewar 0.08 Transfer LNTD contents to CryoSys storage dewar 0.50 Disconnect LNTD from CryoSys dewar 0.17 Move LNTD from CryoSys to mezzanine pick point 0.17 Move LNTD from mezzanine back to elevator 0.50 Load LNTD onto elevator 0.08 Ascend LNTD from cavern to surface level 0.07 Unload LNTD from elevator 0.08 Move LNTD from elevator to surface dewar fill station 0.25 Total 4.05

Number of APATF CBX 3 # CBXHours per day 24 hrs/dayTest duration of one dual APA 96 hrs/test

4.0 day/testNumber of APA pairs tested per CBX 25 tests/CBxTotal APA Tests across all CBX 75 # tests

LN2 consumption per CBX per themal cycle 2,972 kg/CBXLN2 saturated density 808 kg/m^3LN2 consumption per CBX per themal cycle 3,679 L/CBXExtra Margin, SF 50%Total LN2 consumption per thermal cycle per CBX 5,519 L/CBX/testUsable LNTD LN2 capacity 1,995 L/transportEstimated LN2 remaining after transport and flash 0.70 thermal efficiencyEffective LNTD LN2 transported 1,397 L/fillFills required per CBX thermal cycle 3.95 fills/CBX/testLN2 consumption per CBX per day during operations 1,380 L/CBx/dayTotal LN2 consumption per day during ops for 3 CBX 4,139 L/dayTotal LN2 per day during ops for 3 CBX w/ losses 5,913 L/day @ 70% efficiencyTotal # of fills per day for 3 CBX 2.96 fills/dayDuration of 1 LNTD refill cycle 4.05 hrs/fillMax # of LNTD fills per day, possible 5.93 fills/daySafety Factor on LNTD fills 2.00 max fills LNTD / min fills req'dMinimum fill labor per CBX per test 16.01 hrs/CBX/testTotal Number of LNTD fills for APATF ops 296 total fillsMinimum fill labor for APATF ops 1,200 hrs/detector

Logistics

• Ross Shaft is primary bottleneck with constraints:– Elevator platform envelope à 1.38 m x 3.6 m x 3.69 m– Elevator weight limit à 5900 kg

• LN2 storage dewar: manufactured by Wessington with 11000 L capacity– 3D Envelope à 1.45 m x 1.6 m x 9 m !

• Must be transported underneath elevator vertically, and slowly tilted near the base of the Shaft to fit within main transport tunnel

– Weight (empty) à 3400 kg • LN2 transport vessel: manufactured by Cryotherm with

2000 L capacity– 3D Envelope à 1.3 m x 1.44 m x 2.9 m – Weight (full of LN2) à 2810 kg


Cryogenic System Footprint

• DUNE cleanroom has finite area à space between CBXs is tight• To limit condensation on CBX outer surface:

– Maintain gap between each CBX ≥ 30 mm


Cryogenic System Footprint (cont.)


Possibly Liquefier solid models; area should be included in Cryogenic System 3D Envelope

Pressure Safety and Reliefs

• MOP ≤ 100 mbarg (1.45 psig)• MAWP ≤ 160 mbarg (2.32 psig)• Assumptions:

– 10 ft (3 m) of piping from CBX to Vent Header – 200 ft (61 m) of piping from Vent Header to Cavern ventilation inlet– Cavern Vent inlet has zero back pressure

• Worst case venting scenario à 2 CBX cold at steady state (9.1 g/s) + 1 CBX cool-down (16.7 g/s peak)– Total flow = 9.1 g/s x 2 + 16.7 g/s == 35 g/s– Max Vent Rate = Total flow + 50% == 52 g/s– Vent Path --> DN25 x 3m + DN50 x 61 m– Total pressure drop = 18 mbar + 52 mbar == 70 mbar– MOP – Total ΔP è 30 mbar margin for CBX operation


dune integration meeting apa test facility (apatf ... · • contamination of ln2 source is...

Documents