1. Update on UT cooling specifications and status of activities LHCb CO2 cooling meeting 8/7/2015 Simone Coelli For the Milano UT group INFN milano 1 Istituto Nazionale di Fisica Nucleare Sezione di Milano

2. Cooling specification document 2 https://edms.cern.ch/document/1487284/1 A revision of the cooling requirement document is uploaded on EDMS Comments from Bart and Burkhard were included A few comments in next slides

3. 3 ± 0.5 °C stability at stave (in time) Table 1 cooling system parameters ± 5 °C operative margin on nominal set point for inlet CO2 temperature knowing that with 2PACL it is possible to set any point

4. 4 Table 2 environment Internal box Lowest admissible temperature For box thermal insulation calculation Operative temperatures Detector staves at nominal operative conditions: Surfaces not heated all but the ASICs and silicon sensors are almost isothermal with the cooling pipe «detector» surfaces are about - 25 °C

5. 5 Table 3 loads Detector Loads are foreseen to decrease uniformly All sensor less powered Independent from powering scheme UT box thermal heat pick-up load: 500 W

6. 6 Thermal figure of merit Thermal figure of merit concept Valid were heat power flux is present Under the ASICs Delta t ASIC over pipe temperature About 20 °C Power density about 1,5 W/ cm2 => ASIC TFoM = about 13 °C cm2/W

7. TRACI TEST 7 Damaged experiment flux needle regulation valve SS-SS2-VH 1/8 inch TRACI v.1 Received needle regulation valve SS-SS4-VH 1/4 inch TRACI v.3 SS-SS2-VH 1/8 inch TRACI v.1 needle was broken inside Perforated and remounted successfully SS-4JB (ball valve) Used to regulate flux If needed to better regulate flux, we can substitute it with the received ¼ inch needle valve

8. TRACI TEST 8 Successfull CO2 circulation into the stave dummy stave CO2 mass flow rate preliminary test = 1 g/s ± 0,05 g/s We can regulate the flux using pump rotation speed Regulating valve installed in the test loop (by-pass is completely open now) SUCCESSFULL COOLING UNTIL – 15 °C Work in progress

9. TRACI TEST work in progress 9 Heaters off CO2 mass flow rate = 1 g/s (0,96-1,04 g/s) upward flow No armaflex T amb 28 °C Pressure accumulator st to P = 30 bar / T sat - 5,6 °C Pressure readings inside 0,1 bar in operation conditions STAVE INLET FLUID PF1, TF1 STAVE OUTLET FLUID PF2, TF2 Stave Pressure drop calculated until now max 0,3 bar Without power and 1 g/s PF3 before regulation valve PF1 PF2 PF0 on the table TF2 TF1

10. TRACI v1 Pictures of TRACI system working conditions

11. TRACI TEST plan 11 Heaters off CO2 mass flow rate = 1 g/s (0,96-1,04 g/s) No armaflex T amb 28 °C Pressure accumulator set to P = 25 bar /T sat -12 °C (AND LOWER UNTIL – 20 °C) Heaters on (0 – 25% - 50% - 75% -100% - 125% - 150% nominal power) CO2 mass flow rate = 1 g/s (0,96-1,04 g/s) No armaflex T amb 28 °C Pressure accumulator set to P = 25 bar /T sat -12 °C (AND LOWER UNTIL – 20 °C) Calculation of inlet and outlet Hentalpy states Energy balance Check with experts..

12. First step test will use a single stave dummy. 12 status of activities and plans for this year PROTOTYPES that could be tested TYPE C/B/A DUMMY STAVES / DIFFERENT SNAKE AND HEAT LOAD UPWARD/DOWNWARD FLOW

13. TRACI TEST 13 Correction of termocouples temperature 02/01/19 00 SCOSTA DA MEDIO misur e TERMOC OPPIE da DAQ 1T124,30,115 PT100 FLUIDO P FLUID O 2T224,20,015 BARa 3T324,3 0,115 TF124,31,2 4T424,1-0,085 5T524,1-0,085 6T624,1-0,085 7T724-0,185 8T824-0,185 9T924-0,185 10T1024-0,185 11T1123,9-0,285 12T1223,8-0,385 13T1323,9-0,285 14T1423,9-0,285 15T1523,9-0,285 16T1624-0,185 17T1724,90,715 18T1824,80,615 19T1925,2 1,015 TF225,11,2 20T2024,30,115 SOMMA TK483,7 MEDIO TK 24,18 5

14. Cobra simulations work in progress 100 Watt from ambient HORIZONTAL PIPE (the only version working) 14

15. Cobra simulations work in progress 200 Watt from ambient HORIZONTAL PIPE (the only version working) 15

16. Cobra simulations work in progress 300 Watt from ambient HORIZONTAL PIPE (the only version working) 16

17. 17 CO2 DISTRIBUTION 4 inlet + 4 outlet per UT half box Internal: 1 manifold distribution for heach half-plane Manifold to stave INLET connection SHOULD INCLUDE A CALCULATED PRESSURE DROP Alternatives: Capillary (problem in the fittings) flow restrictor (+ filter ) One per stave (the smaller ID is 0,254 mm) Swagelok 6LV-4-VCR-6-DM—…010p to….100P To be tested in real operation condition

18. Back-up slides 18

19. 19

20. UT DETECTOR one half box UNDER INVESTIGATION USING ONE LONG CAPILLARY/MINIPIPE THAT IS A DISTRIBUTED PRESSURE DROP CONNECTING EACH STAVE PIPE INLET; EXTERNAL MANIFOLD DISTRIBUTED DELTAP The detector coolant distribution system goal is to give the correct flow distribution using balanced pressure drop in the circuit => THE DEGREE OF FREEDOM WE HAVE IN THE DESIGN IS IN THE INLET COOLING LINES (INTERNAL DIAM, LENGTH, ROUGHNESS) This sketch is to satisfy the “half panel” service modularity required

21. 21 COOLING SPECIFICATIONS DUMMY STAVES 6,5 W each * 6 heaters titanium pipe Real geometry 18 W 5 group heaters 18 W 5 group heaters

22. Titanium to swagelok 1/8 glued + stiffener 22 Dummy stave with attached reworked fittings on the Titanium snake pipe (dummy C central stave) Glued joint ARALDITE 2011 Ti pipe –SS reworked dummy fitting tested without stiffener up to 200 bar for several times

23. 23 THE PURE CO2 SATURATION CURVE CORRELATES TEMPERATURE AND PRESSURE (INSIDE THE EVAPORATION CHANNEL) - 20 °C TO - 30 °C COOLING FLUID OPER. TEMP. => 10 TO 20 bar COOLING FLUID OPER. PRESSURE SU blow-off test 12-13 bar

24. 24 H lv (liq.=> vap.) = 280 kJ/kg H lv (liq.=> vap.) LATENT HEAT OF VAPORIZATION FOR CO2 FROM THE CO2 PRESSURE-HENTALPY DIAGRAM 10 TO 20 bar COOLING FLUID OPER. PRESSURE RANGE At 10 bar (- 40 °C) H lv= 320 kJ/kg