A double stage Stirling cryocooler for long life space borne operation is under development at CEA/SBT. The cooler has been designed to provide simultaneously cooling capacities of 1 Watt at 50 K and 5 Watts at 190 K, with maximum efficiency.
An original technology using hydrodynamic gas bearings and clearance seals for contactless operation has been developed and successfully assessed.
A twin piston pressure oscillator and a two stage cold expander both using hydrodynamic gas bearings and clearance seals have been designed and fabricated. The performance of the oscillator have been reported elsewhere and are summarised in this paper.
The cold finger uses a linear motor and a magnetic spring is inserted between both bearings for resonant operation. Linear motor performance, magnetic spring stiffness and resonant frequency experiments have been carried out.
Preliminary pneumatic and thermal tests of the overall system are in progress.
This work is undertaken in collaboration with AEROSPATIALE and L'AIR LIQUIDE.