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At least 829 records · Page 46

ECLS for the NASA CDG Space Station model

This paper describes the approaches to Environmental Control and Life Support (ECLS) loop closure that have been studied for a permanently manned Space Station, by the NASA Concept Development Group (CDG) and industry. The paper explains the rationale behind the level of the loop closure chosen for ECLS expendables and why this level was chosen. The paper also explains potential synergistic interactions, between ECLS subsystems and other vehicle systems, which can lessen vehicle expendable penalties and help simplify required ECLS hardware, interfaces and control. Of particular significance are the potential interfacing of the ECLS subsystem which concentrates the metabolic CO2 removed from the atmosphere, with propulsion system resistojets and the use of cryogenic boiloff to satisfy crew metabolic needs. The paper shows the trade-offs that must be performed in order to make a selection from available options.

Cushman, R. J.↗

Advanced life support control/monitor instrumentation concepts for flight application

Development of regenerative Environmental Control/Life Support Systems requires instrumentation characteristics which evolve with successive development phases. As the development phase moves toward flight hardware, the system availability becomes an important design aspect which requires high reliability and maintainability. This program was directed toward instrumentation designs which incorporate features compatible with anticipated flight requirements. The first task consisted of the design, fabrication and test of a Performance Diagnostic Unit. In interfacing with a subsystem's instrumentation, the Performance Diagnostic Unit is capable of determining faulty operation and components within a subsystem, perform on-line diagnostics of what maintenance is needed and accept historical status on subsystem performance as such information is retained in the memory of a subsystem's computerized controller. The second focus was development and demonstration of analog signal conditioning concepts which reduce the weight, power, volume, cost and maintenance and improve the reliability of this key assembly of advanced life support instrumentation. The approach was to develop a generic set of signal conditioning elements or cards which can be configured to fit various subsystems. Four generic sensor signal conditioning cards were identified as being required to handle more than 90 percent of the sensors encountered in life support systems. Under company funding, these were detail designed, built and successfully tested.

Heppner, D. B.↗

Controlled ecological life support systems (CELSS) flight experimentation

The NASA CELSS program has the goal of developing life support systems for humans in space based on the use of higher plants. The program has supported research at universities with a primary focus of increasing the productivity of candidate crops plants. To understand the effects of the space environment on plant productivity, the CELSS Test Facility (CTF) has been conceived as an instrument that will permit the evaluation of plant productivity on Space Station Freedom. The CTF will maintain specific environmental conditions and collect data on gas exchange rates and biomass accumulation over the growth period of several crop plants grown sequentially from seed to harvest. The science requirements for the CTF will be described, as will current design concepts and specific technology requirements for operation in micro-gravity.

Kliss, M.↗

A geostatistical analysis of small-scale spatial variability in bacterial abundance and community structure in salt marsh creek bank sediments

Small-scale variations in bacterial abundance and community structure were examined in salt marsh sediments from Virginia's eastern shore. Samples were collected at 5 cm intervals (horizontally) along a 50 cm elevation gradient, over a 215 cm horizontal transect. For each sample, bacterial abundance was determined using acridine orange direct counts and community structure was analyzed using randomly amplified polymorphic DNA fingerprinting of whole-community DNA extracts. A geostatistical analysis was used to determine the degree of spatial autocorrelation among the samples, for each variable and each direction (horizontal and vertical). The proportion of variance in bacterial abundance that could be accounted for by the spatial model was quite high (vertical: 60%, horizontal: 73%); significant autocorrelation was found among samples separated by 25 cm in the vertical direction and up to 115 cm horizontally. In contrast, most of the variability in community structure was not accounted for by simply considering the spatial separation of samples (vertical: 11%, horizontal: 22%), and must reflect variability from other parameters (e.g., variation at other spatial scales, experimental error, or environmental heterogeneity). Microbial community patch size based upon overall similarity in community structure varied between 17 cm (vertical) and 35 cm (horizontal). Overall, variability due to horizontal position (distance from the creek bank) was much smaller than that due to vertical position (elevation) for both community properties assayed. This suggests that processes more correlated with elevation (e.g., drainage and redox potential) vary at a smaller scale (therefore producing smaller patch sizes) than processes controlled by distance from the creek bank. c2002 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.

Non-NASA Center↗

Plasma physics and environmental perturbation laboratory. Volume 1: Executive summary

Space physics and plasma physics experiments that can be performed from the space shuttle were identified. Potential experiment concepts were analyzed to derive requirements for a spaceborne experiment facility. The laboratory, known as the Plasma Physics and Environmental Perturbation Laboratory consists of a 33-foot pallet of instruments connected to a 25-foot pressurized control module. Two 50-meter booms, two subsatellites, a high power transmitter, a multipurpose accelerator array, a set of deployable canisters, and a gimbaled instrument platform are the primary systems deployed from the pallet. The pressurized module contains all the control and display equipment required to conduct the experiments, and life support and power subsystems.

Source record↗

2021 NE-XF Pathways Internship Student Showcase Presentation

Branch of Fluid Mechanics concern with the mechanics and properties of gases and its application to engineering systems. Applications of Pneumatics in the Aerospace systems: (1) Flight Hardware - Reaction Control, Systems, Rocket Pressure Fed Systems (2) Ground Operations – Valve Actuation, Inert Environment (Purge), Tube Drying/Cleaning NE-XFPneumatics Engineering provides design & operation expertise to support EGS. Commodities used at KSC systems: Gaseous Helium (GHe) Gaseous Oxygen (GO2) Gaseous Nitrogen (GN2) Breathing Air (BAIR) Support other subsystems: LH2, LO2, Ground Main Propulsion System (GMPS), etc.

Environmental and Life Support Systems↗

NASA Space Technology Draft Roadmap Area 13: Ground and Launch Systems Processing

This slide presentation reviews the technology development roadmap for the area of ground and launch systems processing. The scope of this technology area includes: (1) Assembly, integration, and processing of the launch vehicle, spacecraft, and payload hardware (2) Supply chain management (3) Transportation of hardware to the launch site (4) Transportation to and operations at the launch pad (5) Launch processing infrastructure and its ability to support future operations (6) Range, personnel, and facility safety capabilities (7) Launch and landing weather (8) Environmental impact mitigations for ground and launch operations (9) Launch control center operations and infrastructure (10) Mission integration and planning (11) Mission training for both ground and flight crew personnel (12) Mission control center operations and infrastructure (13) Telemetry and command processing and archiving (14) Recovery operations for flight crews, flight hardware, and returned samples. This technology roadmap also identifies ground, launch and mission technologies that will: (1) Dramatically transform future space operations, with significant improvement in life-cycle costs (2) Improve the quality of life on earth, while exploring in co-existence with the environment (3) Increase reliability and mission availability using low/zero maintenance materials and systems, comprehensive capabilities to ascertain and forecast system health/configuration, data integration, and the use of advanced/expert software systems (4) Enhance methods to assess safety and mission risk posture, which would allow for timely and better decision making. Several key technologies are identified, with a couple of slides devoted to one of these technologies (i.e., corrosion detection and prevention). Development of these technologies can enhance life on earth and have a major impact on how we can access space, eventually making routine commercial space access and improve building and manufacturing, and weather forecasting for example for the effect of these process improvements on our daily lives.

Clements, Greg↗

Payload/cargo processing at the launch site

Payload processing at Kennedy Space Center is described, with emphasis on payload contamination control. Support requirements are established after documentation of the payload. The processing facilities feature enclosed, environmentally controlled conditions, with account taken of the weather conditions, door openings, accessing the payload, industrial activities, and energy conservation. Apparatus are also available for purges after Orbiter landing. The payloads are divided into horizontal, vertical, mixed, and life sciences and Getaway Special categories, which determines the processing route through the facilities. A canister/transport system features sealed containers for moving payloads from one facility building to another. All payloads are exposed to complete Orbiter bay interface checkouts in a simulator before actually being mounted in the bay.

Ragusa, J. M.↗

Development of a prototype regeneration carbon dioxide absorber

A prototype regenerable carbon dioxide absorber was developed to maintain the environmental quality of the portable life support system. The absorber works on the alkali metal carbonate-bicarbonate solid-gas reaction to remove carbon dioxide from the atmosphere. The prototype sorber module was designed, fabricated, and tested at simulated extravehicular activity conditions to arrive at optimum design. The unit maintains sorber outlet concentration below 5 mm Hg. An optimization study was made with respect to heat transfer, temperature control, sorbent utilization, sorber life and regenerability, and final size of the module. Important parameters influencing the capacity of the final absorber unit were identified and recommendations for improvement were made.

Patel, P. S.↗

Advanced support systems development and supporting technologies for Controlled Ecological Life Support Systems (CELSS)

A methyl acetate reactor was developed to perform a subscale kinetic investigation in the design and optimization of a full-scale metabolic simulator for long term testing of life support systems. Other tasks in support of the closed ecological life support system test program included: (1) heating, ventilation and air conditioning analysis of a variable pressure growth chamber, (2) experimental design for statistical analysis of plant crops, (3) resource recovery for closed life support systems, and (4) development of data acquisition software for automating an environmental growth chamber.

Simon, William E.↗

NASA Environmental Control and Life Support Technology Development for Exploration: 2021 to 2022 Overview

Over the past year, significant progress has occurred in technology development, ground testing, and ISS technology demonstrations within the NASA Environmental Control and Life Support (ECLSS) community. This paper provides a technology development update in the following capability areas: life support, environmental monitoring, fire safety, and logistics. Technologies for exploration missions must be reliable in their operation which support crewed mission phases. However, they also need to be put into a reduced use or dormant states to support uncrewed mission phases and then successfully and reliably returned to a nominal state to support crew. Multi-year demonstration of systems operation across this range of conditions are essential to mission success. Project overviews will include how the current activity supports the goal of multi-year demonstrations, planned follow-on activities, and what type of exploration mission elements are targeted for infusion. Technologies must be demonstrated and validated early enough to inform early exploration element milestone reviews (mission concept reviews, systems requirement reviews and no later than preliminary design reviews) so that supporting vehicle systems can also be matured. Consequently, for low technology readiness activities, it is important to also identify which mission elements they might infuse into and how they may offer potential operational, dormancy, or mass benefits. While low TRL technology timelines may not support initial mission needs, early infusion is still reasonable with sufficient testing to validate performance and reliability.

Life Support↗

Unlocking the Future of Aircraft Manufacturing: The Environmental Benefits of Laser Patterning for Surface Enhancement of Aircraft-Certified Alloys

Surface protection and functional modification of aircraft-certified aluminum alloys are essential for corrosion resistance, durability, and long-term airworthiness. At the same time, increasingly restrictive environmental regulations motivate the development of alternatives to legacy wet-chemical surface treatments. This study presents an integrated assessment of ultrafast femtosecond laser surface texturing as a surface functionalization approach for Aluminum 6061 alloys within an aerospace manufacturing and sustainability context. Ultrashort-pulse laser processing enables controlled micro- and nano-scale surface topographical modification with limited thermal impact, allowing adjustment of wettability and surface functionality while preserving bulk material integrity. As a dry and contactless process, femtosecond laser treatment eliminates the use of hazardous chemicals, reduces consumable inputs, and generates minimal secondary waste. A streamlined cradle-to-gate life cycle assessment conducted in accordance with ISO 14040/14044 indicates a lower global-warming potential per functional unit compared with conventional surface treatments, including anodization, plasma-assisted coatings, and organic coating systems. Complementary qualitative analyses addressing environmental health and safety, supply-chain risk, and ESG alignment indicate potential advantages related to occupational safety, regulatory compliance, waste management, and end-of-life recyclability. The investigation is performed on planar Aluminum 6061 reference surfaces with a treated area of 25 mm 2 , providing a controlled laboratory-scale basis for analyzing process behavior, functional surface modification, and associated environmental metrics. Within this defined scope, the results support further evaluation of femtosecond laser surface texturing as a surface engineering option for future aerospace manufacturing.

corrosion resistance↗

The development status of candidate life support technology for a space station

The establishment of a permanently-manned Space Station has recently been selected as the next major step in the U.S. space program. The requirements of a manned operations base in space appear to be best satisfied by on-board Environmental Control/Life Support Systems (ECLSS) which are free from, or have minimum dependence on, use of expendables and the frequent earth resupply missions which are part of systems using expendables. The present investigation is concerned with the range of regenerative life support system options which NASA is developing to be available for the Space Station designer. An air revitalization system is discussed, taking into account devices concerned with the carbon dioxide concentration, approaches of CO2 reduction, oxygen generation, trace contaminant control, and atmospheric quality monitoring. Attention is also given to an independent air revitalization system, nitrogen generation, a water reclamation system, a waste management system, applications of the technology, and future development requirements.

Samonski, F. H., Jr.↗

High-Capacity Spacesuit Evaporator Absorber Radiator (SEAR)

Future human space exploration missions will require advanced life support technology that can operate across a wide range of applications and environments. Thermal control systems for space suits and spacecraft will need to meet critical requirements for water conservation and multifunctional operation. This paper describes a Space Evaporator Absorber Radiator (SEAR) that has been designed to meet performance requirements for future life support systems. A SEAR system comprises a lithium chloride absorber radiator (LCAR) for heat rejection coupled with a space water membrane evaporator (SWME) for heat acquisition. SEAR systems provide heat pumping to minimize radiator size, thermal storage to accommodate variable environmental conditions, and water absorption to minimize use of expendables. We have built and tested a flight-like, high-capacity LCAR, demonstrated its performance in thermal vacuum tests, and explored the feasibility of an ISS demonstration test of a SEAR system. The new LCAR design provides the same cooling capability as prior LCAR prototypes while enabling over 30% more heat absorbing capacity. Studies show that it should be feasible to demonstrate SEAR operation in flight by coupling with an existing EMU on the space station.

Izenson, Michael G.↗

Flow field measurements in the cell culture unit

The cell culture unit (CCU) is being designed to support cell growth for long-duration life science experiments on the International Space Station (ISS). The CCU is a perfused loop system that provides a fluid environment for controlled cell growth experiments within cell specimen chambers (CSCs), and is intended to accommodate diverse cell specimen types. Many of the functional requirements depend on the fluid flow field within the CSC (e.g., feeding and gas management). A design goal of the CCU is to match, within experimental limits, all environmental conditions, other than the effects of gravity on the cells, whether the hardware is in microgravity ( micro g), normal Earth gravity, or up to 2g on the ISS centrifuge. In order to achieve this goal, two steps are being taken. The first step is to characterize the environmental conditions of current 1g cell biology experiments being performed in laboratories using ground-based hardware. The second step is to ensure that the design of the CCU allows the fluid flow conditions found in 1g to be replicated from microgravity up to 2g. The techniques that are being used to take these steps include flow visualization, particle image velocimetry (PIV), and computational fluid dynamics (CFD). Flow visualization using the injection of dye has been used to gain a global perspective of the characteristics of the CSC flow field. To characterize laboratory cell culture conditions, PIV is being used to determine the flow field parameters of cell suspension cultures grown in Erlenmeyer flasks on orbital shakers. These measured parameters will be compared to PIV measurements in the CSCs to ensure that the flow field that cells encounter in CSCs is within the bounds determined for typical laboratory experiments. Using CFD, a detailed simulation is being developed to predict the flow field within the CSC for a wide variety of flow conditions, including microgravity environments. Results from all these measurements and analyses of the CSC flow environment are presented and discussed. The final configuration of the CSC employs magnetic stir bars with angled paddles to achieve the necessary flow requirements within the CSC.

Cell Culture↗

Design considerations for the CELSS test facility engineering development unit

The NASA Controlled Ecological Life Support System (CELSS) Program has the goal of developing life support systems for humans in space based on the use of higher plants. The program has supported research at universities with a primary focus of increasing the productivity of candidate crop plants. To understand the effects of the space environment on plant productivity, the CELSS Test Facility (CTF) has been developed as an instrument that will permit the evaluation of plant productivity on Space Station Freedom. The CFT will maintain specific environmental conditions and collect data on gas exchange rates and biomass accumulation over the growth period of several crop plants grown sequentially from seed to harvest. To better understand the systems needed to support plants and maintain the evironmental conditions required by CTF, an Engineering Development Unit (EDU) is being constructed at NASA Ames Research Center (ARC) in the Advanced Life Support Division. The EDU will provide the means of testing and evaluating hardware solutions to CTF requirements. This paper reviews the CTF science and functional requirements, and provides a description of the EDU objectives, design approach, subsystem descriptions, and some of the technology tools employed in accomplishing the design.

Kliss, M.↗

High-Capacity Spacesuit Evaporator Absorber Radiator (SEAR)

Future human space exploration missions will require advanced life support technology that can operate across a wide range of applications and environments. Thermal control systems for space suits and spacecraft will need to meet critical requirements for water conservation and adaptability to highly variable thermal environments. This paper describes a Space Evaporator Absorber Radiator (SEAR) that has been designed to meet performance requirements for future life support systems. A SEAR system comprises a lithium chloride absorber radiator (LCAR) for heat rejection coupled with a space water membrane evaporator (SWME) for heat acquisition. SEAR systems provide heat pumping to minimize radiator size, thermal storage to accommodate variable environmental conditions, and water absorption to minimize use of expendables. We have built and tested a flightlike, high-capacity LCAR, demonstrated its performance in thermal vacuum tests, and explored the feasibility of an ISS demonstration test of a SEAR system. The new LCAR design provides the same cooling capability as prior LCAR prototypes while enabling over 30% more heat absorbing capacity. Studies show that it should be feasible to demonstrate SEAR operation in flight by coupling with an existing EMU on the space station.

Izenson, Michael G.↗

Formulation of consumables management models, executive summary

Future manned space programs that have increased launch frequencies and reusable systems require an implementation of new consumables and systems management techniques that relieve both the operations support personnel and flight crew activities. Analytical models and techniques were developed which consist of a Mission Planning Processor (MPP) with appropriate consumables data base, methods of recognizing potential constraint violations in both the planning and flight operations functions, and flight data files for storage/retrieval of information over extended periods interfacing with flight operations processors for monitoring of the actual flights. Consumables subsystems considered in the MPP were electrical power, environmental control and life support, propulsion, hydraulics and auxiliary power.

Torian, J. G.↗