Propylene Loop Heat Pipe Design and Thermal Performance
Résumé
A pair of propylene Loop Heat Pipes has been designed, built, tested and delivered for use in cooling the two main Ocean Color Instruments for the Plankton, Aerosol, Cloud, ocean Ecosystem satellite, due to be launched by NASA in 2023. The target operating condition was to convey 15W-25W in the -40C to -20C temperature range. All wetted materials were stainless steel, while aluminum saddles and radiator panels were used to enhance heat spreading. The evaporator wick was 100mm long and used micron scale sintered powder. The radiator, at 660mm x 326mm, was machined from a block rather than being assembled as a composite. Maximum heat transport was measured at 180W. A special round of testing to assess the capacity of the secondary wick qualified the design. The units were delivered in a flat configuration to enable thorough ground testing, and then bent into the final configuration for installation into the instrument.