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The International Space Station (ISS) Port 1 (P1) External Active Thermal Control System (EATCS) Ammonia LeakAmmonia is used in the Starboard 1 (S1) and Port 1 (P1) External Active Thermal Control System (EATCS) to cool the pressurized modules, and some of the external electrical power distribution hardware. Leaks that develop in these critical cooling systems that deplete in-line tanks can ultimately result in loss of cooling, which can have devastating impacts to the mission, science and crew onboard the ISS. A slow ammonia leak was initially observed from the P1 EATCS in 2011, but later in 2013 the leak rate began to accelerate. The ammonia inventory eventually began to decay exponentially, raising concerns that the inventory could drop to levels where the system would not be operational.The Robotic External Leak Locator (RELL) was built and launched to the ISS to detect and help locate ammonia leaks using the ISS Robotic Arm and remote ground operator control without constant crew involvement. RELL pinpointed the ammonia leak to the two flexible jumper hose assemblies connecting one of two fluid loops in one of the three deployable radiators to the P1 EATCS. The ammonia inside the two hose assemblies and that radiator fluid loop was isolated and vented to space in 2017. This stopped the leak and an Extravehicular Activity was conducted to remove the two hose assemblies so they could be returned to ground for further Test, Teardown and Evaluation (TT&E). The purpose of this presentation is to discuss this leakage scenario and the TT&E efforts.
Document ID
20190030293
Document Type
Presentation
External Source(s)
Authors
Cowan, Darnell T. (NASA Johnson Space Center Houston, TX, United States)
Bond, Timothy A. (NASA Johnson Space Center Houston, TX, United States)
Metcalf, Jordan L. (NASA Johnson Space Center Houston, TX, United States)
Date Acquired
August 28, 2019
Publication Date
August 26, 2019
Subject Category
Fluid Mechanics and Thermodynamics
Report/Patent Number
JSC-E-DAA-TN70723
Meeting Information
2019 Thermal and Fluids Analysis Workshop(Newport News, VA)
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
Technical Review
Single Expert

Available Downloads

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