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 Dilution System
Planck System Performances Planck system provide 1.6K and 100mK cooling stages from a 4.5K cooler Cooling power of 400 and 0.2 Isotopes flow of 18 mol/s 4He and 6 mol/s 3He Needs HP (285 Bar) storage ( 4 X 50L ) for 2 years Critical pneumatical system for flow control and maintain a high purity Full integration of the heat exchanger with the focal plane and the wires ( thermalization ) (*) + thermalization power of the FP supports and the wires between 1.6K and 0.1K
CCDR Concept
Separation and performances at high 4He flow (F.Martin PhD thesis, 2009)
BLISS Study Mass Budget – Cold H/W (including IOB)< 150 kg 50 kg for SAFARI Thermal Budget – K (FPI Total) – (FPI Total) Volume FPI Position Warm Electronics
Double stage ADR solution Grating Spectrometers + screens > 9kg at 50 mK ! 0.4 W at 50mK
Carbon fiber supports Advantage to C/F rods
4K stage 1.7K stage 300mK stage 50mK / instruments C/F rods Screens Heat intercept between mK 200 mol/s 4He 30 mol/s 3He W/O locking system for launch !
System aspects Cryo device integrated functions : -Cooling detectors -Instrument support -Part of the read/out chain (cables thermalization / cold amplifiers ) ? 3Helium circulation (30 mol/s - 5/200 mBar) Cold pump Room temp pump Isotopes storage Integration (Planck-like)
Solutions for 3He pump Space qualified mechanical pumps – JAXA JT3HE compressor adaptation – Thales PT compressor adaptation – High speed drag pump Cryo pump – Twente development for Darwin => The two options will kept
High speed drag pump Creare technology (space qualified) Technical proposal under discussion RPM Gas bearing Adixen commercial product CEA/AirLiquide design study RPM Mag bearings
Cryogenic pump Darwin H2 JT system Design adaptation for the dilution Need a check valve adaptation for low pressure Acceptable heat load at 15K/50K (100mW)
Conclusions Cooling performances achieved 1 50mK (TRL3-4) Re-use of the BLISS case for B-POL Need to have a complete engineering model – 0 G still demonstration – Pump choice / development (prob. Two solutions) Supported by Cnes (PhD A. Volpe) and ESA (ITI) Objective TRL4 in June 2011