Lukasz ZwalinskiATLAS IBL CO 2 cooling 1 CO 2 cooling system for Insertable B Layer detector into the ATLAS experiment L. Zwalinski, C. Bortolin, T. Blaszczyk, S. Berry, F. Corbaz, G. Glonti, O. Crespo-Lopez, J. Godlewski, M. Lippert, S. Nichilo, M. Ostrega, M. van Overbeek, P. Petagna, E. Roeland, B. Verlaat, S.Vogt, M. Zimny

ATLAS experiment Lukasz ZwalinskiATLAS IBL CO 2 cooling 2 Diameter: 25m Length: 46m Barrel Toroid Length: 26m Overall weight: 7000 tonnes ~100 million electronic channels 3000 km of cables

IBL detector Lukasz ZwalinskiATLAS IBL CO 2 cooling 3 ATLAS IBL Info: Number of staves: 14 Number of modules per stave (single/double FE-I4) 32 /16 Pixel size (f; z) 50, 250 um Required cooling power: 1500W T evap min at 1.5kW = C T evap max at 1.5kW = C

Where do we come from? Lukasz ZwalinskiATLAS IBL CO 2 cooling 4 2PACL conceptPrevious experiencePreparation studyATLAS IBL AMS 2 LHCb Velo MARCO CORA

CO 2 cooling plants Lukasz ZwalinskiATLAS IBL CO 2 cooling 5 Main system elements: 2 independent, redundant cooling plant cores 2 independent, redundant two stage chillers 1 common accumulator with redundant control Common interconnection piping for maintenance operations including vacuum pump Integrated internal by pass and small evaporator for stand-by operation Designed cooling power at C = 3kW

CO 2 cooling primary chiller Lukasz ZwalinskiATLAS IBL CO 2 cooling 6 Main system elements: R404a 2 stage compressor Air cooled and water cooled condenser Hot gas bypass & liquid injection Commercial standard refrigeration chiller capable to work from zero to full IBL load!

Cooling system inside the service cavern Lukasz ZwalinskiATLAS IBL CO 2 cooling 7

CO 2 distribution from plant into detector Lukasz ZwalinskiATLAS IBL CO 2 cooling 8 ~100m concentric transfer line from manifolds to plant in service cavern UX15

Transfer lines Lukasz Zwalinski ATLAS IBL CO 2 cooling 9 UX15 Experimental cavern Transfer line installed in October ‘13 USA15 Service cavern Service gallery

Fluid distribution inside toroid area Lukasz ZwalinskiATLAS IBL CO 2 cooling 10 3kW dummy load heater Manual valves Sensors and inst. connection Junction box Manifold box Rotatable connector Vacuum flexible to vac. manifold

Detector interconnections Lukasz ZwalinskiATLAS IBL CO 2 cooling staves of 70W each connected via concentric 29m long loops to manifolds in the muon area Cross flow of the CO 2 Required min. vacuum level mbar Standard vacuum components capable to work in the vicinity of the magnetic filed. Required constant pumping

Control system Lukasz ZwalinskiATLAS IBL CO 2 cooling 12 Controls: Schneider PLCs: 2x Premium + 1x 340 M all in technical network SCADA based on Siemens WinCC OA 3.11 PLC and SCADA software based on UNified Industrial COntrol System (UNICOS) Continuous Process Control CPC6 of CERN WAGO Ethernet IP distributed I/Os in privet network Access control via e-groups Long term data storage in LHC logging data base Grouped alarms send via LASER to CERN Control Centre (CCC) Communication to the Detector Control System (DCS) uses Data Interchange Protocol (DIP) Additional direct MODBUS communication to DCS for critical data Hard wired signals connected to Detector Safety System (DSS) Siemens local touch screens used for the redundancy and safety needs Electricity and power distribution: Standard industrial components (ABB, Siemens, etc.) 24V DC hot swappable redundant power supplies Few numbers for ATLAS IBL CO 2 cooling software: ~230k lines of PLC code 366 alarms and interlocks 81 user interface panels PH-DT standard common for ATLAS and CMS CO 2 cooling systems (including TIF and P5 of CMS) AnaDO5 Analog13 Analog Alarm43 Analog Digital12 Analog Input90 Analog Input Real51 Analog Output16 Analog Output Real10 Analog Parameter100 Analog Status10 Controller16 Digital Alarm319 Digital Input149 Digital Output68 Digital Parameter20 Local20 OnOff32 ProcessControlObject4 Word Status12 IBL A UNICOS object list Fully commissioned!

User interfaces Lukasz ZwalinskiATLAS IBL CO 2 cooling 13

Typical cold operation Lukasz ZwalinskiATLAS IBL CO 2 cooling 14 Pressurization of the system Cool down -40’C set-point reached 1kW 2kW 3kW -35’C set point In current configuration 3kW is to much for -40’C operation, unable to hold set-point (green line)

Typical cold operation Lukasz ZwalinskiATLAS IBL CO 2 cooling 15 Capable of maintaining set point from 0 to 3kW 0W 500W 1000W 1500W 2000W 2500W Compressor at full speed, temperature of liquid increases Margin of sub cooling must be maintained. >10’C for safe operation Chiller temperature and CO 2 liquid Junction box temperature SP = -35’C

Typical reaction on load changes Lukasz ZwalinskiATLAS IBL CO 2 cooling 16 Junction box saturation Accumulator saturation CO 2 liquid temperature Turbo-mode bit Junction box heat load (1.5 kW) Chiller super heating (Control input) Freon injection valve Aggressive control in turbo-mode turbo-mode needed to remain sub cooling Temporarily accumulator cooling stops to give priority to CO 2 liquid cooling

Summary Lukasz ZwalinskiATLAS IBL CO 2 cooling 17 All cooling units are running relatively smooth. All electrical and control verification and checks are completed. Commissioning continues via junction box until final connection with the detector is completed. First observations shows: -40’C operation is more critical than expected -35’C operation is okay up to 3kW More heat load in liquid pump, meaning a higher needed minimum sub cooling. Direct effect on the lowest possible temperature.

Lukasz ZwalinskiATLAS IBL CO 2 cooling 18 Thank You. ATLAS IBL CO 2 cooling team: L. Zwalinski, C. Bortolin, T. Blaszczyk, S. Berry, F. Corbaz, G. Glonti, O. Crespo-Lopez, J. Godlewski, M. Lippert, S. Nichilo, M. Ostrega, M. van Overbeek, P. Petagna, E. Roeland, B. Verlaat, S.Vogt, M. Zimny