Low-Cost Space Based Cryocoolers

The objective of the proposed effort is to design and build a bread-board version of a Low-Cost Space cooler including a novel, contact bearing system based on the previously done work in Phase I. The Attollo approach to creating low-cost space cryocoolers (based on our cryocooler design experience) is to create a pulse tube Stirling cryocooler with fewer parts, no flexure springs, ultra-low friction and wear contact bearings, and 3-D printed heat exchanger and regenerator structures. Fewer parts in the design mean fewer parts to qualify and that can fail. The elimination of flexure springs removes the least reliable design component, and the low-friction contact bearing approach will deliver long-lifetime by design. These design choices will produce intrinsically high MTTF coolers. The hybrid contact/gas bearing used in the compressor will also increase the yield at the initial low speed stiction test, keeping production costs low. Simulations with Stirling optimization software (“Sage”) indicate that our current design (Figure 1) will deliver 5 Watts of heat lift with a 77K cold stage temperature at an efficiency of > 5% and a lifetime of >50,000 hours. Our vision is to be able to produce space cryocoolers as part of our upcoming cryocooler product line at less than $250k per unit. Approved for Public Release | 22-MDA-11102 (22 Mar 22)