An Advanced Loop Heat Pipe for Cryogenic Applications



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47th International Conference on Environmental Systems


A loop heat pipe (LHP) is a very versatile heat transfer device which can transport a large heat load over a long distance with a small temperature difference. All LHPs currently servicing orbiting spacecraft are designed to operate in the room temperature range. Future space telescopes and space-based Earth resource imaging satellites require passive cryogenic heat transport devices that can thermally couple remote cryocoolers to sensor or instrument of interest while providing the capability of payload vibration/jitter isolation, implementation of redundant coolers, and coupling of multiple sensors to a common heat sink. All of these requirements can be satisfied by using a cryogenic LHP (CLHP). Although the development of CLHPs faces several technical challenges, NASA Goddard Space Flight Center has devoted extensive efforts in developing CLHP technology over the past decade and has made significant progress. In particular, the combination of the innovative ideas of using a secondary capillary pump to manage the parasitic heat gain and using a hot reservoir to reduce the system pressure under the ambient condition has led to the successful development of the CLHP. Several CLHPs charged with nitrogen and hydrogen were built and tested in thermal vacuum chambers. These CLHPs demonstrated reliable start-up and robust operation during power cycle and sink temperature cycle tests.


Jentung Ku, NASA Goddard Space Flight Center (GSFC), USA
Treim Hoang, TTH Research, Inc., USA
ICES201: Two-Phase Thermal Control Technology
The 47th International Conference on Environmental Systems was held in South Carolina, USA on 16 July 2017 through 20 July 2017


Two-Phase Heat Transfer, Loop Heat Pipe, Cryogenic Applications