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Original Date: 04/26/1999
Revision Date: 01/18/2007
Best Practice : Environmental Control and Life Support Systems
One of Marshall Space Flight Center’s (MSFC’s) capabilities is developing and testing life support systems for manned space missions. Typical systems include oxygen for breathing; food storage; filtering canisters for removing contaminants within the vehicle; stored water for drinking and washing; collection/storage containers for urine; and collection/treatment/storage containers for solid waste. As the manned space program grew, requirements changed and new technologies were developed. Early missions such as Mercury, Gemini, and Apollo used expendable throwaway systems because of the vehicles’ weight constraints and short flight durations. Regenerative systems and techniques were also impractical due to size, weight, and cost. However, the Space Shuttle program introduced a new era for manned space missions. As flights became longer in duration, systems were needed to support the regeneration of life support resources within the space vehicle. The continued use of expendables for these systems became too costly in terms of logistical support.
The International Space Station (ISS) is the next-generation vehicle, and requires regenerative life support systems to effectively remain in space. The design concept of the space station includes separate modules, airlocks, and nodes which are docked and assembled together to form a large pressurized enclosure. This enclosure must be capable of supporting manned operations for indefinite periods of time. Provisions (Figure 2-3) for sustaining a crew on the ISS will be controlled by the space station’s Environmental Control and Life Support Systems (ECLSS). NASA has delegated the responsibility of designing and testing ECLSS to MSFC. To support this assignment, an extensive design and test program is underway, including the development of the Core Module Integration Facility (CMIF) which will test ECLSS and its subsystems:
Water Reclamation System Has undergone analysis since 1990 with extensive testing and a continuous, 146-day cycle of operation.
Vapor Compression Distillation Unit Designed to process urine, has completed life testing requirements, and is now being used as a development unit to support a future spaceflight experiment.
Biofilm Test Determines if buildups are occurring by circulating clean and dirty water through onboard plumbing components.
Internal Thermal Control System Simulates the temperature and humidity control system of the space station, and is used to test fans, blowers, pumps, heat exchangers, etc.
The CMIF also contains the Common Module Simulator which is the same shape and diameter as the ISS core module. This unit contains all services (e.g., water, electrical, gas) needed to operate the various subsystems independently or as an integrated system. A new addition to the CMIF is a Habitation Module Simulator which has been outfitted to support ISS-sustaining engineering efforts. A complete set of ECLSS hardware has been installed in this simulator, so parallel operations can be performed with ISS operations to respond quickly to any on-orbit situation that might occur.
Figure 2-3. Space Station Regenerative ECLSS Flow Diagram
For more information see the
Point of Contact for this survey.
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