| As modern infrared sensors continue to place extraordinary requirements on the thermal management systems designed to cool them, improved cooling methods must be explored. This thesis is a discussion of the state of the art in cryogenic thermal management systems for infrared sensors, as well as advanced concepts that are currently being explored.;Trade studies are shown for selecting the most cost-effective base cooling system. Liquid and solid cryostats are compared with modern cryocooler systems, and critical selection criteria such as lifetime and performance parameters are explored. It is concluded that Gifford McMahon cryocooler systems are most cost effective for long operating lifetimes, where cryostats are preferred for short operating lifetimes or for systems with very low parasitic heat loads.;The concept of using thermal storage units coupled with cryocooler systems in order to eliminate transmitted vibrations is explored. Magnesium alloys with extremely high specific heats at low temperatures are introduced. Phase change materials are also explored; however, it is concluded that there are no feasible phase change materials in the 40 K to 50 K operating region.;Heat load analyses are performed on the various components that make up the PATI thermal management system. Optimization techniques are explored for designing focal plane wire cables. It is concluded that Manganin wires are best when short wires are needed, whereas stainless steel wires are preferred when minimal heat loads are desired. Other common heat load analyses are demonstrated for remaining heat transfer modes. |
