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Close Cycle Dilution for Space. Ph. Camus, G . Vermeulen, G. Chaudhry, A. Benoit, F. Martin B-POL Workshop, IAP Paris, 29th July 2010. Planck Open D ilution S ystem. Planck System Performances. Planck system provide 1.6K and 100mK cooling stages from a 4.5K cooler
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Close Cycle Dilution for Space Ph. Camus, G. Vermeulen, G. Chaudhry, A. Benoit, F. Martin B-POL Workshop, IAP Paris, 29th July 2010
Planck System Performances • Planck system provide 1.6K and 100mK cooling stages from a 4.5K cooler • Cooling power of 400mW @1.6K and 0.2mW(*) @100mK • Isotopes flow of 18 mmol/s 4He and 6 mmol/s 3He • Needs HP (285 Bar) storage ( 4 X 50L ) for 2 years • Criticalpneumatical system for flow control and maintain a highpurity • Full integration of the heatexchangerwith the focal plane and the wires ( thermalization ) (*) + thermalization power of the FP supports and the wiresbetween 1.6K and 0.1K
Separation and performances athigh 4He flow (F.MartinPhDthesis, 2009)
BLISS Study • Mass Budget • Cold H/W (including IOB)< 150 kg • 50 kg for SAFARI • Thermal Budget • 15 mW @ 4.5 K (FPI Total) • 5mW @1.7K (FPI Total) • Volume • FPI Position • Warm Electronics
Double stage ADR solution GratingSpectrometers + screens > 9kg at 50 mK ! 0.4 mW at 50mK
Carbonfiber supports Advantage to C/F rods
W/O locking system for launch ! Screens 300mK stage C/F rods 50mK / instruments Heatinterceptbetween300-50mK 200 mmol/s 4He 30 mmol/s 3He 1.7K stage 4K stage
System aspects Cryodeviceintegratedfunctions : • Cooling detectors • Instrument support • Part of the read/out chain (cablesthermalization / cold amplifiers ) ? 3Helium circulation (30 mmol/s - 5/200 mBar) • Cold pump • Room temppump • Isotopes storage • Integration (Planck-like)
Solutions for 3He pump • Spacequalifiedmechanicalpumps • JAXA JT3HE compressor adaptation • Thales PT compressor adaptation • High speed drag pump • Cryopump • Twente development for Darwin => The two options willkept
High speed drag pump Crearetechnology (spacequalified) Technicalproposalunder discussion 200000 RPM Gasbearing Adixen commercial product CEA/AirLiquide design study 60000-120000 RPM Magbearings
Cryogenicpump • Darwin H2 JT system • Design adaptation for the dilution • Need a check valve adaptation for low pressure • Acceptable heatloadat 15K/50K (100mW)
Conclusions • Cooling performances achieved 1mW @ 50mK (TRL3-4) • Re-use of the BLISS case for B-POL • Need to have a complete engineering model • 0 G stilldemonstration • Pumpchoice / development (prob. Two solutions) • Supported by Cnes (PhD A. Volpe) and ESA (ITI) • Objective TRL4 in June 2011