The ODIN Cool Box (Cryostat) developed by ACR and SOS.
The design process of the ODIN Cool Box contains two conflicting demands - high stability versus high thermal insulation. In order to achieve these goals the inner structure is suspended with kevlar fibres. Very low thermal conductivity combined with high strength for the fibres makes this a possible solution.
According to launch specification for the satellite, the thickness of the kevlar suspension was chosen in such a way that the lowest resonance frequency was forced up to the 150 Hz region. For these calculations I used ANSYS FEM program.
A test cryostat was vibrated to a 10 g level to check performance of the suspension. The permanent displacement after the vibrational testing was surprisingly low - less than one tenth of a millimeter. This was measured by a laser diode reflex in the cool box.
The noble art of wrapping a space cryostat.About 30 layers of M.L.I. (Multi Layer Insulation) are wrapped around the inner box .
One of the biggest heat contribution come from three major openings for the signals.In order to reduce radiation losses kevlar baffles were used. The thermal performance and integration to the space cooler from B.A
(British Aerospace) was tested at SSC (Swedish Space Corporation) in a vacuum chamber. We reached about
120-130 K with full heat-load.
The cooler could lift about 2W at 100k.
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