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CO 2 cooling needs for the CBM experiment at FAIR. Johann M. Heuser GSI, Darmstadt, Germany for the CBM collaboration. start of operation: 2018. Scientific pillars at FAIR: Compressed Baryonic Matter Atomic and Plasma Physics & Applications
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CO2cooling needs for the CBM experiment at FAIR Johann M. Heuser GSI, Darmstadt, Germany for the CBM collaboration Work Package 13 - CO2 Cooling
start of operation: 2018 • Scientific pillars at FAIR: • Compressed Baryonic Matter • Atomic and Plasma Physics & Applications • Nuclear Structure, Astroand Reaction physics • Antiproton Annihilation Physics Facility for Anti-proton and Ion Research SIS100, SIS300 SIS18 CBM • primary, secondaryandstoredbeams • SIS-100 / SIS-300 • protons: 2 - 29/89 GeV • ions: 2 - 14/44 AGeV, sNN= 1.9 - 4.5/4.2 - 9 GeV • intensities:upto 109ions per secondat CBM UNILAC GSI FAIR Work Package 13 - CO2 Cooling
start of operation: 2018 Facility for Anti-proton and Ion Research FAIR GSI Work Package 13 - CO2 Cooling
Facility for Anti-proton and Ion Research civil construction has started in 2011 Work Package 13 - CO2 Cooling
Facility for Anti-proton and Ion Research civil construction has started in 2011 a few days ago ... Work Package 13 - CO2 Cooling
Silicon Tracking System Compressed Baryonic Matter Experiment Fixed-target heavy-ion physics experiment. Heavy-ion collisions at the high-rate and high-matter density frontier. Silicon tracking, vertexing, particle identification, time-of-flight, calorimetry. Work Package 13 - CO2 Cooling
Central detector system of the experiment: charged-particles: tracking, momentum measurement Silicon Tracking System • Challenges: • high interaction rates, • up to 107 nuclear reactions per second, each producing up to ~700 charged particles • pile-up free reconstruction • high segmentation, fast read-out • high power dissipation • low mass, δp/p < ~ 1% radiation lengths • large-area: ~ 4 m2 detectors, • confined volume: ~ 2 m3 in dipole magnet special attention to cooling TDR submitted to FAIR in December 2012 Work Package 13 - CO2 Cooling
STS system engineering read-out electronics ion beam silicon microstrip sensors Work Package 13 - CO2 Cooling
Cooling requirements: Sensor cooling at high rad. area around beam pipe due to increased leakage currents FEB cooling to remove dissipated power completely (because of the above) Silicon sensors must stay below -7°C at all times (on or off) to avoid thermal runaway of the irradiated silicon to avoid reverse annealing Maximum power dissipated by electronics: 2 × 20 kW dissipated in top and bottom layer (200 W/FEB Box) enormous heat dissipation in a small volume Maintenance-free in inaccessible detector area STS Cooling Requirements Work Package 13 - CO2 Cooling
Cooling of sensors with minimal material budget no tubes, no liquid, etc. ~ 1 mWheat dissipation from innermost sensors Envisioned solution: Cooling with free or forced gas flow Cooling of of FEBs under extreme space constraints 40 kW in 2 layers inside of ~ 2 m3 thermal box very high density of electronics, i.e. dense heat dissipation Envisioned solution: Evaporative CO2 Cooling STS Cooling Challenges Work Package 13 - CO2 Cooling 10
Power Dissipation Station 1 <1W@263K, I(T) ~ T2 Work Package 13 - CO2 Cooling
Cooling requirements • 200 W per front-end electronics box • 42 kW for total STS • effective cooling, little space ! • best cooling agent: CO2 • volumetric heat transfer vs. tube diameter CERN COURIER May 31, 2012 • in cooperation with CERN (EU-FP7 CRISP): • realization of a 1 kW CO2 test cooling unit TRACI-XL • electronics box with 8 FEBs • attached to a cooling plate • 2 m long capillary of 1.6 mm diameter Work Package 13 - CO2 Cooling
Next Step 1 Build simple open CO2 test stand to evaluate heat transfer for our geometries: • FEB box with (dummy) electronics • couple to cooling and measure heat transfer*) *)Two-phase pressure drop as well as two-phase heat transfer is hard to predict accurately as the liquid/vapor flow pattern are very non-uniform measurement 20 W per board, 10 boards per box 1,80 m of cooling line in contact with FEBblock CO2 in CO2 out Work Package 13 - CO2 Cooling
First Step: Blow System for experimental verification at Tübingen Group H.R. Schmidt, Univ. Tübingen Work Package 13 - CO2 Cooling
Next step 2 More complex experimental evaluation with TRACI-XL (closed system) • 0.25 kW system (TRACI, CERN) • GSI opts for 1 kW version: TRACI-XL • under design and component procurement at GSI with CRISP support Jorge Sanchez Rosado + University of Tübingen, Germany (Group Prof. H.R. Schmidt) • good for hands-on learning of CO2 technology • adapt cooling plate to realistic geometry, manifolds, parallel vs. serial lines, … • questions on a full-size system (42 kW): • costs? • how many units/racks of what power? • spatial requirements? Work Package 13 - CO2 Cooling
CO2 cooling plant in the CBM Cave Underground hall: Length: 37 mWidth: 22 m Height: 17 m gas storage CO2plant pipe length ~ 70 m Work Package 13 - CO2 Cooling