We report the development and initial testing of the Lockheed Martin first-article, single-stage, compact, coaxial, Fast Cooldown Pulse Tube Microcryocooler (FC-PTM). The new cryocooler supports cooling requirements for emerging large, high operating temperature (105-150K) infrared focal plane array sensors with nominal cooling loads of ~300 mW @105K @293K ambient. This is a sequel development that builds on our inline and coaxial pulse tube microcryocoolers reported at CEC 2013⁷, ICC18^8,9, and CEC2015¹⁰. The new FC-PTM and the prior units all share our long life space technology attributes, which typically have 10 year life requirements¹. The new prototype microcryocooler builds on the previous development by incorporating cold head design improvements in two key areas: 1) reduced cool-down time and 2) novel repackaging that greatly reduces envelope. The new coldhead and Dewar were significantly redesigned from the earlier versions in order to achieve a cooldown time of 2-3 minutes-- a projected requirement for tactical applications. A design approach was devised to reduce the cold head length from 115mm to 55mm, while at the same time reducing cooldown time. We present new FC-PTM performance test measurements with comparisons to our previous pulse-tube microcryocooler measurements and design predictions. The FC-PTM exhibits attractive small size, volume, weight, power and cost (SWaP-C) features with sufficient cooling capacity over required ambient conditions that apply to an increasing variety of space and tactical applications.

Date Published: 19 September 2016
PDF: 11 pages
Proc. SPIE 9978, CubeSats and NanoSats for Remote Sensing, 99780L (19 September 2016); doi: 10.1117/12.2238285

Published in SPIE Proceedings Vol. 9978:
CubeSats and NanoSats for Remote Sensing
Thomas S. Pagano, Editor(s)