Ground Testing of a 10 K Sorption Cryocooler Flight Experiment (BETSCE)
The Brilliant Eyes Ten-Kelvin Sorption Cryocooler Experiment (BETSCE) is a Space Shuttle side-wall-mounted flight experiment designed to demonstrate 10 K sorption cryocooler technology in a space environment. The BETSCE objectives are to: (1) provide a thorough end-to-end characterization and space performance validation of a complete, multistage, automated, closed-cycle hydride sorption cryocooler in the 10 to 30 K temperature range, (2) acquire the quantitative microgravity database required to provide confident engineering design, scaling and optimization, (3) advance the enabling technologies and resolve integration issues, and (4) provide hardware qualification and safety verification heritage.
BETSCE ground tests were the first-ever demonstration of a complete closed-cycle 10 K sorption cryocooler. Test results exceeded functional requirements, as the BETSCE cooler was able to cooldown from 70 K to < 11 K in 95 seconds, sustain a simulated detector heat load of 100 mW for > 20 minutes, achieve a minimum temperature of 9.5 K with load, and demonstrate excellent repeatability with continued cycling. The sorbent beds achieved a compression ratio of 8.3 × 105, and were able to recycle the system in under 5.5 hours. This paper summarizes functional and environmental ground test results, planned characterization tests, important development challenges that were overcome, and valuable lessons-learned. The planned spaceflight experiment will enable early insertion of sorption cryocooler technology into future long-life, low-vibration, spacecraft sensor cooling applications in the 10 to 30 K temperature range.
KeywordsStorage Tank Phase Change Material Liquid Hydrogen Cold Head Pressure Container
Unable to display preview. Download preview PDF.
- 1.Jones, J. A., “Hydride Absorption Refrigerator System for Ten Kelvin and Below,” Proceedings of the Third Cryocooler Conference. NBS Special Publication 698, NBS, Boulder, CO, (1984).Google Scholar
- 2.Johnson, A. L. and Jones, J. A., “Evolution of the 10 K Periodic Sorption Refrigerator Concept,” Proceedings of the 7th International Cryocooler Conference. PL-CP-93-1001, Phillips Laboratory, Kirtland AFB, NM, (1993), pp. 831-853.Google Scholar
- 3.Wu, J. J., Bard, S., Boulter, W., Rodriguez, J., and Longsworth R., “Experimental Demonstration of a 10 K Sorption Cryocooler Stage,” Advances in Cryogenic Engineering, Vol. 39, Plenum Press, New York, NY (1994), in press.Google Scholar
- 4.Bard, S., Fujita, T., Wade, L., Rodriguez, J., and Wu, J. J., “Development of a Periodic 10 K Sorption Cryocooler,” Proceedings of the 7th International Cryocooler Conference, PL-CP-93-1001, Phillips Laboratory, Kirtland AFB, NM, (1993), pp. 854–866.Google Scholar
- 5.Bard, S., Cowgill, P., Rodriguez, J., Wade, L., Wu, J. J., Gehrlein, M., and Von Der Ohe, W., “10 K Sorption Cryocooler Flight Experiment (BETSCE),” Proceedings of the 7th International Cryocooler Conference. PL-CP-93-1001, Phillips Laboratory, Kirtland AFB, NM, (1993), pp. 1107–1119.Google Scholar
- 6.Bhandari, P. and Bard, S., “Thermal Systems Design and Analysis for a 10 K Sorption Cryocooler Flight Experiment,” AIAA 28th Thermophysics Conference, AIAA 93-2825, Orlando, FL (1993).Google Scholar
- 7.Bowman, BETSCE SBA, “Fabrication and Testing of the Metal Hydride Sorbent Bed Assembly for a Periodic 10 K Sorption Cryocooler,” 8th International Cryocoolers Conference, Vail Colorado, June 28–30, 1994.Google Scholar