Thermo-mechanical activities at Valencia

1. 8th International Workshop on DEPFET Detectors and applications Thermo-mechanical activities at Valencia V. Castillo, C. Lacasta, A. Oyanguren, P. Ruiz (IFIC - Valencia) 21/9/2011

2. Outline  Mock-up status at VLC  Studies of air flow cooling: - Effect of CO2 cooling + air flow at several temperatures on the ladders  Conclusions  Plans at VLC Arantza Oyanguren 2 8th International Workshop on DEPFET Detectors and Applications

3. Mock-up CO2 open system Nitrogen liquidDewar (cooled air) Thermally isolated box withdryatmosphere Mock-up IR camera chiller Arantza Oyanguren 3 8th International Workshop on DEPFET Detectors and Applications

4. Mock-up • Mock-up status: • - Mechanical dummy temporarily fixed in the CrCo sample: • (plastic nut + screw ended with a wire embedded in the hole) • Thermal grease for the thermal contact • One resistor sample in the outer layer • - Set voltages: • Sensor: 12 V  P ~ 1W • Switchers: 3V  P ~ 0.25 W • DCDs/DHPs: 20V  P ~2.5 W It works! (appart from the left switchers) Arantza Oyanguren 4 8th International Workshop on DEPFET Detectors and Applications

5. Mock-up Calibration tool for the IR camera: ( depends on the material) Al box filled with coolant: cooled down with chiller, heated with heaters. Study material   ~ 0.65 (broken) mechanical dummy switcher DCD/ DHP DCD/ DHP sensor Marker Tipp -ex Al Tape 1 Cu Tape 2 Kapton grease  ~ 0.35 T= 90ºC  ~ 0.18 T= -10ºC Arantza Oyanguren 5 8th International Workshop on DEPFET Detectors and Applications

6. Air flow studies (vair (inlet) ~ 2m/s) - Effect of blowing air at room temperature: (corrected emmisivity) DCD/ DHP DCD/ DHP DCD/ DHP DCD/ DHP Camera position • The air flow (at room T) decreases • and homogenizes the temperature • along the detector. •  Decreases T ~ 15 C •  Max T along the ladder 18C 8C Arantza Oyanguren 6 8th International Workshop on DEPFET Detectors and Applications

7. Air flow studies - Cooling down the end flanges with CO2 - Blowing air/N2 at different temperatures (cooled down with N2 liquid atmosphere) (vair (inlet) ~ 2m/s) 25 ºC T (ºC) Camera position (corrected emmisivity) Looking at the central region of the sensor: • Detector on: T ~ 45ºC • Effect of CO2 + air flow : T ~ 20ºC (or below) Looking at the edges: - Bumps ?? (crab legs) - With CO2 + air flow T along the ladder ~ 20ºC (!?) Arantza Oyanguren 7 8th International Workshop on DEPFET Detectors and Applications

8. Air flow studies • Problems of IR transparence due to the • thickness of the detector: Detector on, CO2 in theendflanges, no air flow - Tipp-ex marks behind in the Cu inner ladder End flanges sensor Present setup switchers Sensor and switchers: expected about same  and behaviour (corrected emmisivity) - sensor - switchers left switchers off T(ºC) Tipp-ex marks behind End flanges Previous setup Camera position Arantza Oyanguren 8 8th International Workshop on DEPFET Detectors and Applications

9. Air flow studies - Detector on, CO2 in theendflanges, cooled air flow - sensor - switchers T(ºC) T~10ºC Effect of IR transparence due to the thickness of the sensor (?) (corrected emmisivity) Camera position • Effect of a polycarbonatesheet (IR opaque) • behindthemechanicaldummy (i.e.between • theinner and outerladders: • A fewdegrees (~3) difference, notobserved • fortheswitchersregion, duetothereflexion • in theinnerladder, seenbythe IR camera • throughthethick sensor. Arantza Oyanguren 9 8th International Workshop on DEPFET Detectors and Applications

10. C. Mariñas simulation Air flow studies • More realistic conditions for the • detector, set voltages so: • Sensor:  P ~ 0.5W • Switchers:  P ~ 0.5W • DCDs/DHPs:  P ~ 8W • Inner cupper ladder covered with a • polycarbonate dummy, opaque to IR Sensor T (ºC) (corrected emmisivity) Camera position Detector on Background (room T) End flanges cooled with CO2 Air flow at room T Air/N2 flow cooled [-8,-15]C Arantza Oyanguren 10 8th International Workshop on DEPFET Detectors and Applications

11. Air flow studies - Sensor region (P~0.5W): Sensor Detector on Background (room T) End flanges cooled with CO2 Air flow at room T T (ºC) Air/N2 flow cooled [-8,-15]C Camera position • Temperature for the sensor when switching on the detector: ~ 60 C • Cooling the endflanges (CO2): T sensor< 25 C (~ room T  to check colder environment) • Blowing air at room T  T sensor < 20 C and homogenus • Blowing cooled air (-8,-15) C  T sensor < 15 C and homogeneus • Tmax along the sensor ~ 10 C (contact + remaining transparence) • For a proper T estimation from the enflanges one should have all detectors on • (but should be ok following the Karlsruhe test • (see next page)) Arantza Oyanguren 11 8th International Workshop on DEPFET Detectors and Applications

12. Air flow studies From Karlsruhe (S. Heindl, Feb 2011) : PT1000s Silicon pieces with resistors (20W each) 120W + CO2 Cooling:  Endflange at < -10 C (most probes) Arantza Oyanguren 12 8th International Workshop on DEPFET Detectors and Applications

13. Air flow studies - Switchers region (P~0.5W): (corrected emmisivity) Detector on Switchers Background (room T) End flanges cooled with CO2 Air flow at room T Air/N2 flow cooled [-8,-15]C T (ºC) Camera position • Only right switcher was operating • Temperature for the switchers when the detector is switched on ~ 40 C • Cooling the endflanges (CO2): T sensor ~ 20-30 C (room T  to check colder environm.) • Blowing air at room T  T sensor < 25 C and homogenus • Blowing cooled air (-8,-15) C  T sensor < 25 C and homogeneus • Small Tmax along the detector < 10 C Arantza Oyanguren 13 8th International Workshop on DEPFET Detectors and Applications

14. Conclusions - Valencia mockup set up and understood. - At present, all tests show:  Cooled air flow decreases the ladder temperature below ~20C  Tmax along the ladder less or around 10C - Valencia activity on thermo-mechanical issues will smoothly decrease in the next year, but at present this setup may be used for any envisaged thermal test In particular: Arantza Oyanguren 14 8th International Workshop on DEPFET Detectors and Applications

15. Mock-up • Test air flow cooling with the CO2 return Until now, air or N2 gaseous cooled by the atmosphere inside the liquid N2 Dewar (-80C) New CO2 exchanged system to cool down the air flow: 1.5m pipe coil at the CO2 return to cool down the air: Air flow temperature in the outlet ~ -5 - 0 C Arantza Oyanguren 15 8th International Workshop on DEPFET Detectors and Applications

16. Plans • Test air flow effect in the inner ladders (mainly for the switchers) through carbon fibers Carbon fibers • Set up the new endflanges of • aluminium and/or stainless steel • (ladders better screwed, better • fixed and better thermal contact) Al samples Arantza Oyanguren 16 8th International Workshop on DEPFET Detectors and Applications

17. Plans • Test possible vibrations in the detectors due to the air flow Capacitive Non-ContactDisplacementdetectors: ATLAS setup Arantza Oyanguren 8th International Workshop on DEPFET Detectors and Applications

18. Backup  Dummy ladders: Polycarbonate Al Cu Heaters Resistor samples Arantza Oyanguren 18

19. Backup  Effect of air velocity - It is enough to have a very low speed flow air to achieve a proper heat dissipation in the ladder (1WT~ 6-7ºC), (Expected behaviour from Carlos simulations) Arantza Oyanguren 19

20. Backup  Inner ladder: heaters (3W) T (C) Air flow T~0C* Air flow T~-20C * CO2, No air flow Camera position * entering in the box; T in the CB? Arantza Oyanguren 20