2018-07-082018-07-082018-07-08ICES_2018_301http://hdl.handle.net/2346/74241Mohammed Ababneh, Advanced Cooling Technologies, Inc.Calin Tarau, Advanced Cooling Technologies, Inc.William Anderson, Advanced Cooling Technologies, Inc.Angel Alvarez-Hernandez, NASAStephania Ortega, NASAJeffery Farmer, NASARobert Hawkins, NASAICES104: Advances in Thermal Control TechnologyThe 48th International Conference on Environmental Systems was held in Albuquerque, New Mexico, USA on 08 July 2018 through 12 July 2018.Copper-water heat pipes are commonly used for thermal management of electronics systems on earth and aircraft, but have not been used in spacecraft thermal control applications to date, due to the satellite industry’s requirement that any device or system be successfully tested in a microgravity environment prior to adoption. Recently, Advanced Cooling Technologies Inc., (ACT), in coordination with engineers from NASA’s Marshall Space Flight Center (MSFC) and Johnson Space Center (JSC) demonstrated successful flight operation of these heat pipes in low-Earth orbit. The testing was conducted aboard the International Space Station (ISS) under the Advanced Passive Thermal eXperiment (APTx) project, a project to test a suite of passive thermal control devices funded by the ISS Technology Demonstration Office at NASA JSC. The heat pipes were embedded in a high conductivity (HiK™) aluminum base plate and subject to a variety of thermal tests over a temperature range of -10 to 38 ºC for a ten-day period. Results showed excellent agreement with both predictions and ground tests. The HiK™ plate underwent 15 freeze-thaw cycles between -30 and 70 ºC during ground testing, and an additional 14 freeze-thaw cycles during the ISS testing. The following was demonstrated during 10 days of testing on the ISS: 1. Successful operation of the copper-water heat pipes and HiK™ plate 2. Ability of the copper-water heat pipes and HiK™ plate to survive multiple freeze/thaw cycles 3. As-designed heat transport via Copper-water heat pipes. 4. Reliable, repeatable start up of Copper-water heat pipes and HiK™ plate from a frozen state. This paper describes the test hardware, ground and flight test campaign, and discusses the results and conclusions of the testing.engCopper-water heat pipesHigh conductivity (HiK™) platesInternational Space Station (ISS)Freeze-thaw cyclesAdvanced Passive Thermal eXperiment (APTx)Passive thermal control devicesPresentation