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

Feedthrough needs for Thermometry for DUNE SP

DUNE FD Joint Cryogenic Instrumentation and Slow Controls Consortium meeting 22/09/2017

• A. Cervera

IFIC - (CSIC & Univ. Valencia)

• J. Maricic

University of Hawaii

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

2

ProtoDUNE-SP

3 T T T T

G

G

W T T T T W T T T T W W W W W W R G

G

T G T-Gradient monitors

Top-bottom

W/F/R Cryostat wall/floor/roof

SIDE view TOP view

T T T W W W W W W R F F F F F F F F F F F F F F F R

high precision (< 5 mk) high precision (<5 mk) low precision (~0.1 K)

Dynamic T-gradient monitor

4

Entire array is 7.5 m high, spanning the full height of protoDUNE LAr volume Temperature profiler moves using stepper motor that moves the rack and pinion gear system connected to rod assembly up to 1 m.

• 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 two sensors at each location for cross- referencing.

• Expect to achieve

required temp. measurement precision of few mK.

1 1 3 2 2 3 Lakeshore RTD temperature sensor PT-102

Hawaii

Static T-gradient monitor

• 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)

5

9 m

12 cm

Preliminary 3D model calibration setup

lakeshore PT102

Valencia

DUNE-SP cryostat ports

6

https://edms.cern.ch/ui/file/1814480/1/LBNF_v2_Roof_Penetrations.pdf

Instrumentation ports

7

Instrumentation ports Requested instrumentation ports

LAr inlets/outlets

8

inlets inlets

• utlets

Erik Voirin DocDB-2617

Everything together

9

APA CPA APA CPA APA

instrumentation ports requested instrumentation ports

LAr inlets LAr outlets

Fluid dynamic simulations

10

z=0

z=5.166 m

z=5.166 m

z=0

Erik Voirin DocDB-2617

behind APAs

11

z=0

z=5.166 m

Behind the APAs there is no much variation since it is the region of the LAr inlets This area is more useful in the pump suction plane

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

12

z=0

z=5.166 m

First HV System Consortium Meeting

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

8/25/2017 13

https://indico.fnal.gov/conferenceDisplay.py?confId=15170

slide from Bo Yu

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

14

z=0

APA APA CPA CPA APA

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

• f T-gradient monitors

15

APA

END WALL

15 cm 150 cm

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

16

APA CPA APA CPA APA

LAr inlets LAr outlets

S S S S S S S S

at inlets at outlets

half way between inlets and outlets

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)

17

APA CPA APA CPA APA

S S S D D S S S S S

LAr inlets LAr outlets

New ports

• Whatever we put there, having

dedicated ports for instrumentation aligned with the middle APA is a good idea, since the electric field is minimised

18

20.2. CF250, currently spare cryogenics. I would request this one for instrumentation I would request a new one here

APA CPA APA CPA APA

D

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

19

S S S D S S S S S

LAr inlets LAr outlets

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 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 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 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 T T T T T T T T T T T T T

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

20 W= array of wall sensors F= floor sensors F F F F W W W

S S S S S S S

W W W W W F F F F F F F

S

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

21

PD-APA racks

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

22

instrumentation ports previously requested instrumentation ports new request