T. Trollier

Low Temperature High Frequency Pulse Tube Cooler Using Precooling

A low-temperature stage pulse tube cooler is under development at CEA-SBT in partnership with Air Liquide (AL/DTA). This stage is designed to operate from an 80 K heat sink and to provide cooling power at 30 K. In a first phase, an experimental setup featuring a Gifford McMahon (GM) cooler as the precooling stage has been manufactured. The regenerator of the pulse tube stage includes a heat exchanger thermally coupled to the GM cold tip. The design is such that the temperature of this heat sink can be varied over a wide range of temperatures. A preliminary tuning of this experimental setup has been done. In this case, stainless steel meshes have been used even in the low-temperature area. The first results are encouraging, as a temperature lower than 30 K has already been achieved. Sensitivity to various parameters such as inertance, frequency, filling pressure and heat intercept temperature has been tested. The heat extracted at the intermediate heat exchanger has been measured using a shunt-type technique and is compatible with the use of our large-heat-lift pulse tube for precooling. For space applications, the precooling could be provided by a passive radiator. In order to increase the performance, we have examined the use of a regenerator material with better specific heat capacity in the cold area. Lead plated meshes have been manufactured and initial experimental results are presented. This cooler will provide inputs for the design of an integrated two-stage pulse tube cooler in the future.

Performance testing of a large heat lift 40 to 80K pulse tube cooler for space applications

A Large heat lift 40 to 80K Pulse Tube Cooler (LPTC) has been designed, manufactured and tested in partnership between AL/DTA, CEA/SBT and THALES Cryogenics BV. The Engineering Model specification of 2.3 W cooling power at 50 K for 10°C rejection temperature and maximum 160 watts electrical input power has been reached. The as built model weighs 5.13 kg. The thermal and mechanical performances are presented and discussed. This work is funded by the European Space Agency (ESA/ESTEC Contract N°18433/04/NL/AR) in the frame of future Earth Observation instruments development.

Slimformer—Self-Limiting Transformer Pre-Prototype and Pilot Plant Design, Construction, and Tests

The current limiting or self-limiting transformer, (CLT) is a multifunctional device, which combines the functions of a power transformer with the functions of a current limiter. The investigated SLIMFormer consists of a room temperature primary winding and a secondary high temperature superconductor (HTS) winding (BSCCO 2223) divided into two parts located on different limbs and up to 4 HTS ring (BSCCO 2212). The primary winding is connected to the electrical network, the secondary winding is intended to supply an HTS cable. As a result the SLIMFormer is an inductive terminal between the room temperature network and a projected HTS cable. For investigation of the SLIMFormer a 100 kVA rating experimental device (pilot plant) was designed, built and tested. The design and optimization aspects as well as the construction of the pilot plant will be presented. The present work is based on the previous 20 kVA SLIMFormer pre-prototype device which was tested at Lab of DEPE BME. The SLIMFormer was investigated experimentally for both sudden short circuit and steady-state (transformer) operational modes. The activation currents were determined for both operational modes with the rated secondary winding turn ratio. SLIMFormer work is being performed as part of an EC funded project, project name: acronym SLIMFormer.

Cryocoolers Development and Integration for Space Applications at Air Liquide

Publisher Summary This chapter reviews cooling technologies and presents the main characteristics and performances of these coolers. Air Liquide Division Techniques Avancees (AL/DTA) has been involved in space cryogenics since several decades in the framework of the European ARIANE program mainly for the launcher liquid cryogens (LH2 and LOx) tanks development, qualification, and manufacturing but also for the design and implementation of the liquefaction, storage and distribution infrastructures on the launching pad at Kourou, Guyana. More recently AL/DTA has extended its space related business by developing and integrating cryocoolers for use onboard the International Space Station (ISS) or to be flown on scientific or commercial satellites payloads. Several technologies, including Brayton, Joule Thomson, Stirling, Pulse Tube and Dilution refrigeration cycles, have been demonstrated. Some of these coolers have been specifically designed and developed to be integrated within ESA or NASA scientific missions (MELFI, CRYOSYSTEM, PLANCK/HFI) to be flown during the next coming years. Space qualification of these coolers has been already achieved or is going on. Development of miniature Brayton and large cooling capacity pulse tube coolers have also been initiated to prepare the next generation of AL/DTA space coolers.

Design of a Miniature Pulse Tube Cryocooler for Space Applications

An Engineering Model (EM) of a Miniature Pulse Tube Cooler (MPTC) has been designed and manufactured. The expected performance of the MPTC were 1240 mW heat lift at 80 K with 288 K ambient temperature and 40 Watts rms maximum input power to the compressor motors. The EM is a U shape configuration operated with an inertance tube. The design and optimisation of the compressor and the Pulse Tube cold finger are described. The thermal performance test results are presented and discussed as well.This work is performed within a Technological Research Project (TRP) funded by ESA (Contract 14896/00/NL/PA).

Latest pulse tube coolers developments of Air Liquide for space

Thanks to important development efforts completed and partial ESA funding, Air Liquide Advanced Technology Division (AL/DTA), is now in position to propose two Pulse Tube cooler systems in the 40-80K temperature range for coming Earth Observation missions such as Meteosat Third Generation, Sentinel 3, etc... The two pulse tube coolers thermo-mechanical units are qualified against environmental constraints. The associated Cooler Drive Electronics is also an important aspect specifically regarding the active control of the cooler thermo-mechanical unit during the launch phase, the active reduction of the vibrations induced by the compressor (partly supported by the French Agency CNES) of course the electrical interfaces with the compressor. This paper details the presentation of the two Pulse Tube Coolers together with the Cooler Drive Electronics aspects.

Air Liquide cryocoolers for space applications

AL/DTA became a major supplier in the field of space cryogenics for the European Space Industry. From MELFI freezer for the International Space Station (ISS) to HERSCHEL and PLANCK satellites for Cosmic Vision, AL/DTA has acquired a large know-how in space cryogenic systems. Convinced by the great interest of Pulse Tube technology for space applications and especially for Earth Observation or Surveillance Tracking, AL/DTA started its first development in mid nineteenths. Then the European Space Agency started to support the development in 2000. Partnerships were launched with CEA/SBT (France) and Thales Cryogenics B.V. (The Netherlands) in order to take the advantage of the competencies and experience of each other. Based on the will to improve important issues such as reliability and mechanical robustness, technology improvements are now available in AL/DTA Pulse Tube coolers. This paper proposes an overview of AL/DTA cryocoolers for space applications following by a detailed description of Pulse Tube Coolers and particularly their integration.

Development of a Large Heat Lift 40–80 K Pulse Tube Cooler for Space Applications

A Large heat lift 40 to 80 K Pulse Tube Cooler (LPTC) is currently under development in partnership between AL/DTA, CEA/SBT and THALES Cryogenics. The Engineering Model (EM) foreseen is aiming to provide 2 W of cooling capacity at 50 K for 10°C rejection temperature and for 125 watts input power to the compressor’s motors. Cold finger development models (DM) have been manufactured with an in‐line architecture and connected to an off‐the‐shelf compressor from Thales Cryogenics. In parallel, the compressor motor has been optimized and prototyped. The various trade‐offs, performed both on the cold finger and compressor side, during the development phase are presented. This work is funded by the European Space Agency (ESA/ESTEC Contract N°18433/04/NL/AR) in the frame of future Earth Observation instruments development.

An Alternative Study for the FIRST Cryostat

FIRST, a European Space Agency (ESA) program, is a multi-user observatory covering the wavelength range from 80 µm to 670 µm. It is the successor of the Infrared Space Observatory (ISO). FIRST will be launched in year 2007 by the ARIANE V launcher together with the PLANCK satellite. It will remain 3.5 years in operation at the second Lagrangian point of the earth – sun system. AIR LIQUIDE / DTA, as contractor of ESA, has performed an alternative study of the complete cryogenic system resulting in the preliminary design of a large Super fluid Helium cryostat at 1.65 K. The cryostat will be composed of an external vacuum vessel supporting the telescope, the sunshield, various external equipment and containing the Helium tank and the instruments. The main HeII tank (2250 litres) will provide cooling power to the three instruments at 1.7 K, 4.3 K and 15 K for a design lifetime of 3.5 years. Before exiting to the outer space, the Helium vapour will cool 3 internal shields between 30 K and 62 K, the external vacuum vessel and the telescope being passively cooled at 80 K. A complex cryostat aperture protected by a radiated baffle will insure the proper propagation of the light from the telescope to the instruments. Two other options have been studied, based on the use of solid Hydrogen and solid Neon. This paper presents AIR LIQUIDE’s baseline design together with the rationales for the trade-offs conducted on the thermal and structural point of view.