Feedthrough needs for Thermometry for DUNE SP A. Cervera IFIC - - PowerPoint PPT Presentation

DUNE FD Joint Cryogenic Instrumentation and Slow Controls Consortium meeting 22/09/2017 Feedthrough needs for Thermometry for DUNE SP A. Cervera IFIC - (CSIC & Univ. Valencia) J. Maricic University of Hawaii

2 Introduction • In order to better understand the DUNE needs in terms of thermometry we would need: 1. to look at the LAr inlets/outlets 2. to look at the fluid dynamic simulations 3. to operate ProtoDUNE • To understand which resolution can we get • Compare the measurements with the simulations • 1 and 2 are possible now, but not 3. For the moment we should plan for enough number of ports (but not too many) , located at convenient locations such that we have some freedom to decide later on the actual sensor mapping • Apologies, I realised one hour ago that I finally forgot to look at this document (I did it in the past), and I didn’t take it into account for this presentation. I’ll do it for next week

3 ProtoDUNE-SP high precision (< 5 mk) high precision (<5 mk) low precision (~0.1 K) G T-Gradient monitors W/F/R Cryostat wall/floor/roof T Top-bottom SIDE view TOP view W R G G G R R T W W T T F F T F T F W W W W F T F T F F W W W W G F T F T F T F T W W T T W T T F F F

4 Dynamic T-gradient monitor Hawaii • High precision relative temp. measurement achieved by movable array, allowing cross- referencing of temperature sensors in-situ . • Immune to changes from lab testing to installation. • Measurement taken in two easy steps with entire array moved up to compare readings from Lakeshore RTD two sensors at each temperature sensor location for cross- PT-102 referencing. • Expect to achieve required temp. Temperature profiler moves using measurement precision of stepper motor that moves the rack and pinion gear system connected to few mK. 3 rod assembly up to 1 m. 3 2 Entire array is 7.5 m high, spanning the full height of 1 2 protoDUNE LAr volume 1

5 Static T-gradient monitor Valencia • 42 sensors, Electric field shielding because is not behind APA • Calibration done in the lab to few ~5 mK. • Sensors/readout have <2 mk precision • Main problem is reproducibility (~5 mK) lakeshore PT102 calibration setup 9 m 12 cm Preliminary 3D model

6 DUNE-SP cryostat ports https://edms.cern.ch/ui/file/1814480/1/LBNF_v2_Roof_Penetrations.pdf

7 Instrumentation ports Instrumentation ports Requested instrumentation ports

8 LAr inlets/outlets Erik Voirin DocDB-2617 inlets inlets outlets

9 Everything together instrumentation ports LAr inlets requested instrumentation ports LAr outlets APA CPA APA CPA APA

10 Fluid dynamic simulations z=0 z=5.166 m Erik Voirin DocDB-2617 z=5.166 m z=0

11 behind APAs Behind the APAs there This area is more useful is no much variation in the pump suction since it is the region of plane the LAr inlets z=5.166 m z=0

12 top and bottom • These areas are very interesting both at pump discharge and pump suction planes, specially at the top • All locations available since they would be above and below ground planes z=5.166 m z=0

slide from Bo Yu https://indico.fnal.gov/conferenceDisplay.py?confId=15170 The Ground Plane • The purpose of the ground plane above the field cage is to shield the fringe field from the CPA/FC from entering the gas ullage to cause breakdown. It also shield the DSS and cryogenic components with sharp features from high electric field. • The top and bottom FC modules are designed to be symmetrical: there is a ground plane by default on the bottom. • The ground plane is stamped from 
 1mm thick stainless steel sheet. 
 With corner radii of 5mm. • The hole edges facing the 
 field cage are rounded 
 to ~ 0.5mm radius. • The grounding of the ground plane should be 
 made away from the APA/CE feedthroughs. - Top: to DSS feedthrough / rail - Bottom: to membrane 13 8/25/2017 First HV System Consortium Meeting

14 far ends • This is the only Z at which we can instrument the entire plane • Must take into account E field: need electrostatic simulations to understand the distance at which sensors can be safely installed z=0 APA APA APA CPA CPA

15 T-gradient monitors • There is 15 cm (???) clearance between APAs and cryostat walls. No movable device can be installed there, but there is space for an static sensor array at some distance from the wall. There are no instrumentation ports right above. I guess we could use the walls to hold the structure • Dynamic T-gradient monitors can be installed on the two far ends. There are 150 cm (???) between end walls and instrumentation ports, so E field should not be very difficult to control. Preferably close to the APAs (field should be very small). It is mandatory to be right below a port • 50 sensors per array, with more granularity at top and bottom might be enough for both kind 15 cm APA of T-gradient monitors 150 cm END WALL

16 Static T-gradient monitors • Install them as close as posible to the ports • Cover inlet and outlets planes and also an intermediate plane • As shown in simulations outlet is more interesting, two locations • Repeat the map in both sides half way between inlets and outlets at inlets at outlets LAr inlets LAr outlets S S S S APA CPA APA CPA APA S S S S

17 Dynamic T-gradient monitors • The middle area (aligned with the APA) is the perfect place for those devices, since there is no need to worry about the E field • However there are no dedicated ports there • Either we request a two new ports (next slide) • or have some E field shielding (I’ll produce some electrostatic simulations for next meeting) LAr inlets LAr outlets S S S S APA CPA D D APA CPA APA S S S S

18 New ports 20.2. CF250, currently spare cryogenics. I would request I would request this one for instrumentation a new one here • Whatever we put there, having dedicated ports for instrumentation aligned with the middle APA is a good idea, since the electric field is minimised

19 Top and bottom grids • We should foresee a grid of high precision sensors at top and bottom to complement the T-gradient monitors and contribute to the 3D map • Those would be below and above the ground planes, as in ProtoDUNE • It is important to have measurements in all four drift volumes • Below un upper limit for the number of sensors: 250 sensors (125 for bottom and 125 for top) • This is just to confirm that the current ports are OK LAr inlets S LAr outlets S S S T T T T T T T T T T T T T APA T T T T T T T T T T T T T T T T T T T T T T T T T T T T CPA T T T T T T T T T T T T T T T D D T T T T T T T T T T T T T APA T T T T T T T T T T T T T T T T T T T T T T T T T T T T CPA T T T T T T T T T T T T T T T APA T T T T T T T T T T T T T S S S S

20 Membrane sensors • We also need a number of standard sensors on the membrane to monitor the cool- down and filling processes (vertical array of ~10 sensors). • No special locations needed. We can use existing ports • To discuss with experts how many arrays we need • Use the Static T-gradient structure to route cables • And some sensors on the floor to check the presence of LAr everywhere when filling begins. To discuss with experts how many we need F= floor sensors W= array of wall sensors S S S S W W W F F F F F F F W W F F F F W W W S S S S

21 racks • Also the location of the slow controls racks matters, since ideally the they should be close to the instrumentation ports. We have to understand that PD-APA racks

22 Next steps • Feedback from you • Understand wha was proposed in this document • Have a look at the racks map • Are confirmed ? Are possible ? • Have a look at the CFD results shown in the previous talk • Better understand everything I said in the talk instrumentation ports previously requested instrumentation ports new request