Miniature Cryogenic Loop Heat Pipe for Flexible and Lightweight Cooling Transport System

"At present, a passive cryogenic cooling technology that is lightweight and flexible for on-gimbal cryogenic cooling applications is non-existent or, at best, incomplete. Cryogenic Capillary Pumped Loops (CCPLs) demonstrated that they were capable ofproviding several watts of cooling at 77K. However CCPLs required intrinsically rigid liquid cooled shields (LCS) that made them impossible for use in across-gimbal cooling applications. An advanced concept of Cryogenic Loop Heat Pipe (C-ALHP) -developed by TTH Research, Inc. - worked extremely well from 70-100K (Nitrogen as working fluid) to 20-30K (Hydrogen). But, like CCPLs, a hot reservoir was needed for the C-ALHP to minimize its system pressure during charging at room temperature. The hotreservoir was a large and heavy cylinder that would make its space utilization impractical.In this Phase I endeavor, TTH Research proposes to develop an innovative passive cryogenic cooling concept - miniature Cryogenic Loop Heat Pipe (mini-CLHP) - that is efficient, lightweight (no hot reservoir), and highly flexible (1/16" transport lines) forcryogenic cooling in the temperature range of 70-120K (Nitrogen or Oxygen), 30-40K (Neon), 20-30K (Hydrogen), or 4-5K (Helium). The proposed miniature Cryogenic Loop Heat Pipe (mini-CLHP) provides a lightweight and flexible cryogenic cooling technology forIR sensors or high temperature superconductor electronics. Potential applications of the technology