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The Avionics Air Assembly Cooling Package which provides cooling for high heat load racks aboard the International Space Station has been designed and developed to balance challenging requirements for noise emissions, emitted vibrations, power usage, weight, and volume. The assembly consists of a high speed selectable flow fan, a compact air-to-water heat exchanger, noise attenuation components, motor controller electronics, and mounting structure. This paper addresses the final hardware configuration and performance characteristics and the successful development program that was required to create the first qualification/flight assembly. It describes the initial component development hardware performance, the initial package integration results, the completed optimization effort, and the final package performance. These optimization cycles, both to improve and reduce component performance, were necessary to attain the desired package results from this highly integrated assembly.

The Water Reclamation and Management System (WRM) for the Environmental Control and Life Support System (ECLSS) has changed dramatically since Space Station Freedom (SSF) Restructure. What was two separate processors: the Potable Water Processor (PWP) and the Hygiene Water Processor (HWP), is now one combined system called the Water Processor (WP). This combined system is required to process the waste hygiene, handwash, and laundry waters, the Temperature and Humidity Control (THC) condensate, Shuttle fuel cell water, and the urine distillate, to produce potable quality water. The WP is composed of four major functions: waste water collection and storage, processed water storage and delivery, contaminant removal, and microbial separation between the waste and processed water. The two water storage and delivery functions are accomplished using vented bellows tanks and pumps.

In the development of advanced thermal control systems for use in hydrogen-powered space vehicles, utilization of the on-board hydrogen fuel as a heat sink for equipment cooling has many advantages. There are, however, significant challenges preventing the cryogenic temperatures of the stored fuel from causing heat transport fluid freezing. A shell and tube heat exchanger was developed to transfer heat from an ECLSS thermal control coolant loop to the cryogenic hydrogen fuel. To mitigate the potential for coolant freezing, it was necessary to recycle hydrogen from the heat exchanger outlet back to the inlet to moderate heat exchanger inlet temperatures. A recycle compressor could have been used with penalties in weight and reliability due to it's complexity. A superior solution was to use an ejector which has no moving parts, and uses the pressure head of the incoming hydrogen to develop the necessary pumping head and transport the hydrogen through the heat exchanger.