Status Report on Fermilab CO2 cooling activities Simon Kwan Fermilab For the Fermilab Cooling Group CO2 system options Pressure drop calculation Simon Kwan - Fermilab TKUpgrade Mtg – CERN – 4/24/09

TKUpgrade Mtg – CERN – 4/24/09 CO2 System We would like to build a prototype CO2 cooling system at Fermilab Goals: for testing the completely assembled pixel half-cylinder (3 half-disks) and gaining operation experience of a CO2 cooling system; design and experience may be expandable and valuable to the final system at P5 or useful for Track/trigger layer R&D at Fermilab Design spec: be able to operate detector at ~18C to -10C; total heat load ~ 1 kW; chiller can cool down to -40C (design with safety margin) Simon Kwan - Fermilab TKUpgrade Mtg – CERN – 4/24/09

CO2 Cooling System Options Three options were considered: Storage tank $ Storage tank with pump (gain experience with pump $$ Closed system $$$ Option Cost Pros Issue Storage tank $16k + CO2 cost Easy and inexpensive to build (rent a 1000L dewar) Can’t run at RT; vent to atmosphere Storage tank + pump to recirculate un-vaporized fluid $66k + CO2 cost Gain experience with a pumped system; extend running time between fills Still can’t run at RT; difficult to find a suitable pump Closed system similar to final system $120k M&S Labor ~ $80k Gain experience and share it with the community; can operate at a wide variety of conditions Cost; refrigeration vendors not interested in small custom orders Simon Kwan - Fermilab TKUpgrade Mtg – CERN – 4/24/09

Effect of Elbow on Pressure Drop Calculation done by Terry Tope Program checked against LHCb piping and in good agreement Also checked with the latest measurements done by Hans Postema and good agreement Simon Kwan - Fermilab TKUpgrade Mtg – CERN – 4/24/09

Pressure Drop Calculation for the BPIX Tube Design Proposal: verify this with the setup that Hans Postema has at CERN with a mechanical L1 assembly Simon Kwan - Fermilab TKUpgrade Mtg – CERN – 4/24/09