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Development of a portable CO2 cooling system for CO2 R&D in HEPBart Verlaat 2nd October 20131Traci projectDevelopment of a portable CO2 laboratory cooling unit called TraciTRACI=Transportable Refrigeration Apparatus for Co2 Investigation.

Development in AIDA framework together with interested partners.Nikhef & CERN lead development with engineering support of the Cracow University of Technology.Co-funding from clients Collaboration with Sheffield, Oxford, Liverpool and Milano?Would be great to boost the project to the next level!

Designed for applications like:Test beam telescope (AIDA)Micro channel development (LHCb)Pixel development (CMS)Detector thermal/mechanical support structure development (Atlas IBL, ILC-TPC)Detector commissioning(Atlas IBL)

Focus on simplicity for easy production in series

Focus on simplicity for easy non expert use

Bart Verlaat 2nd October 2013Traci design overviewThe need for laboratory CO2 cooling is in the order of several 100 watt from room temperature down to -40C.Capacity is a function of temperature.A kw version under design in collaboration with GSI (Traci-XL)

Stable CO2 temperature, heat load independent

System must be easy to operate by non expert usersOn/off button + temperature set pointStand-alone operation (PC only for monitoring or sending set point commands)

Simplified concept called I-2PACL.Modified 2PACL concept developed for AMS and LHCb.Several functions are integrated for a simpler use and operation2PACL = 2-Phase Accumulator Controlled LoopI-2PACL = Integrated 2PACL (several 2PACL functions are integrated into 1 component)I-2PACL concept is patent pending (CERN&Nikhef)

Bart Verlaat 2nd October 2013I-2PACL concept2-Phase Accumulator Controlled LoopIntegrated2-Phase Accumulator Controlled LoopPatented !(patent owners: CERN & NIKHEF)Used in LHCb-Velo, Atlas IBL & CMS-Pixel

Bart Verlaat 2nd October 2013

Transportable Refrigeration Apparatus for CO2 Investigation

Brrrrrrr!TRACI-1a (LHCb)TRACI-1b (Atlas)T R A C I

Portable laboratory cooling unitCooling power Temperature range Turn keyVery simple to operate fridge like

TRACI-2 (Uni GVA, CMS, KeK)Bart Verlaat 2nd October 2013Typical Traci performance, stable cooling over a large temperature range

Liquid CO2

Evaporative CO2ExperimentSub cool protectionBart Verlaat 2nd October 2013

Current Traci Capacity

Traci-2 PrototypeJulabo FP40-METraci capacity is comparable with a Julabo FP40-ME thermostatic bath cooler Bart Verlaat 2nd October 2013Traci 1&2 design

Foam box with CO2 pipingDoor panel with control interfacesOff-the shelve R404a condensing unitConditioner and relay based control logicCO2 liquid pumpCO2 accumulatorCO2 transfer hose

Other sideBart Verlaat 2nd October 2013Traci experiencesTraci-1&2 LHCb, Atlas and CMS has now been running for a decent amount of time. Several lessons learned:Operation of the systems turns out to be easy, no experts were needed for operation.Protection against empty start up incorporated. Users are not looking at the numbers apparently (also when you tell them to do so).Serious pump wear problem, chosen gear pump is not suitable for long term CO2 pumping.

Traci set-up in Atlas SR1

Traci set-up for IBL stave tests

Traci set-up for LHCb micro channel testsBart Verlaat 2nd October 2013Pump issuesCO2 is a problematic fluid to pumpVery low viscosity (15% of water)Limited or no lubricationLow pumping efficiencyHigh system pressure

No reliable small pump on the market found so far.Currently using Gather gear pumpsLong duration use of current Tracis show short and variable life times of Gather pumps.

Exploring different new pump optionsHNP pump3m pumpLewa pump (LHCb style)Design special pump in house

LHCb pump with excellent track record too big for small systems.Being installed in KEK system, but severe performance degradation at colder temperature

Problem giving gather pump3Mpump under study (Too big for a small Traci)

Lewa pump: reliable but heavy (and pulsating)Large and expensive HNP pumpToo small? HNP pumpBart Verlaat 2nd October 2013Gather pump behavior

Atlas-SR1 1 pump, slowly wearing outCMS 3 pumps in half of the SR1 time1st dead2nddeadStill aliveWhy CMS dies and SR1 not? No idea..Bart Verlaat 2nd October 2013Traci SR1

Elapsed timeRun time without stopsZoomed inBart Verlaat 2nd October 2013Traci CMS

Bart Verlaat 2nd October 2013Pump requirementsFor a 300Watt system based on 50% VQLiquid density range: 780 - 1130 kg/m3Liquid viscosity range: 0.07 - 0.2 cP (0.07 at start-up, nominal 0.15 to 0.2 cP)Trange: -50'C to 20'CFlowrate: 5 g/s => 270 ml/minMinimum sub cooling of inlet liquid: 3'CPressure head: 10 bar (at 0.15 cP viscosity)Static design pressure: 110 barEfficiency: >15% (dT over pump must remain 25HzOil freeLeak tight < 0.1 g/*y CO2Limited liquid pollution due to wear. (Avoid rubbing concepts)Maintenance: Pump should be able to operate full time without intervention for at least 1 year.

What are your specific needs?Bart Verlaat 2nd October 2013HNP 7255 pump

RequirementCurrent TraciBart Verlaat 2nd October 2013Future Traci developmentsNow working on Traci-3, with improvements on:Control: PLC control includedDifferent pump

Traci-3 is build with AIDA funds

Traci-3 designTraci-3 assembly has startedBart Verlaat 2nd October 2013

Future goals of the Traci project

GOAL: General purpose CO2 laboratory coolercompetitive with water / glycol / silicon oil chillersSize reductionHigh risk of contamination of expensive equipment by leaking FluidsCO2-I-2PACL is cleanCO2-I-2PACL has a very accurate distant temperature controlSmall hardware in experimentBart Verlaat 2nd October 2013

Traci-2 for KEK/DesyFor reliability reasons Traci-KeK was supplied with a Lewa pump (LHCb - Track record)Performance degradation expected due to too large pump.KeK specs allow a performance degradation.Question for us was: How much?New configuration, new surprises?Status of today:Exploration has started and 1st signs look positiveFurther tuning needed to deliver a solid product and give us the experience for further development.Bart Verlaat 2nd October 2013

Traci KeK (With Lewa)Bart Verlaat 2nd October 2013Traci-2 capacity estimate

Loss of cooling power at low temperatures Traci-Lewa (0.16 lpm)Traci-Lewa (0.28 lpm)Traci-GatherKeK RequirementCalculated capacity based on 50% vapor quality250W accu heaterPreliminaryBart Verlaat 2nd October 2013Traci collaborationIf Liverpool, Oxford, Sheffield and Milano can join that would be perfect!Work packages: Redesign Traci concept for easy production (Outsourcing, so we can order for demand)Prototype productionPump developmentWith industryTest stand at CERNControl developmentUnder control at CERNHow to continue?I look forward in a good working collaboration!

Bart Verlaat 2nd October 2013