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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
NASA NTRS2023

Quiet Spacecraft Cabin Ventilation Fan: Vibration Measurements Results

Quiet, efficient fans with minimal vibrations are needed to maximize the mechanical life of atmospheric revitalization system fans used for human life support systems for long duration space exploration missions. Several metal spacecraft cabin ventilation fan prototypes have been designed, built, and tested at the NASA Glenn Research Center Acoustical Testing Laboratory. Tests performed in 2021 of the first prototype of the metal fan measured vibrations greater than desired at design point speed and backpressure conditions. To try to reduce those vibrations, a second prototype of the fan design was developed which included a new lighter rotor with a tighter balance tolerance, a new collet to attach the rotor to the motor shaft more securely and repeatably, and a new bracket to center and hold the motor in the fan centerbody more precisely. The second prototype of the fan was tested in 2023 and the vibrations were measured with the fan operating at design point speeds in isolation but not throttled to design point back pressure conditions since it was not installed with inlet and exhaust ducting. Peak vibration was reduced from 4 mm/s to 1 mm/s. This paper is part of a series of reports documenting the performance of the prototype fan.

Fan↗
NASA NTRS1976

A prototype carbon dioxide and humidity control system for Shuttle mission extension capability

This paper describes an advanced regenerable carbon dioxide (CO2) and humidity control system being developed for the NASA Johnson Space Center. The system offers substantial weight advantages in comparison with the baseline Shuttle Orbiter expendable, lithium hydroxide CO2 removal system for extended missions beyond the nominal design of 4 men for 7 days. The regenerable system offers a potential weight savings of 431 kg for a 7-man 30-day mission. A regenerable sorbent material designated as HS-C coadsorbs CO2 and water vapor from the cabin atmosphere and desorbs the CO2 and H2O vapor overboard when exposed to the space vacuum. In addition to a comparison of the regenerable system with the baseline Shuttle expendable system, HS-C mission simulation test results and the flight prototype regenerable system currently being fabricated are presented. The paper shows the integration of the system into the Shuttle Orbiter vehicle; exclusive of cryogenic fuel-cell power expendables, the available packaging envelope is sufficient to stow all expendables necessary for HS-C operation on 30-day extended missions.

Cusick, R. J.↗
NASA NTRS2011

Compact and Lightweight Sabatier Reactor for Carbon Dioxide Reduction

The utilization of CO2 to produce life support consumables, such as O2 and H2O, via the Sabatier reaction is an important aspect of NASA s cabin Atmosphere Revitalization System and In-Situ Resource Utilization architectures for both low-earth orbit and long-term manned space missions. In the current International Space Station (ISS) and other low orbit missions, metabolically-generated CO2 is removed from the cabin air and vented into space, resulting in a net loss of O2. This requires a continuous resupply of O2 via water electrolysis, and thus highlights the need for large water storage capacity. For long-duration space missions, the amount of life support consumables is limited and resupply options are practically nonexistent, thus atmosphere resource management and recycle becomes crucial to significantly reduce necessary O2 and H2O storage. Additionally, the potential use of the Martian CO2-rich atmosphere and Lunar regolith to generate life support consumables and propellant fuels is of interest to NASA. Precision Combustion, Inc. (PCI) has developed a compact, lightweight Microlith(Registered TradeMark)-based Sabatier (CO2 methanation) reactor which demonstrates the capability of achieving high CO2 conversion and near 100% CH4 selectivity at space velocities of 30,000-60,000 hr-1. The combination of the Microlith(Registered TradeMark) substrates and durable, novel catalyst coating permitted efficient Sabatier reactor operation that favors high reactant conversion, high selectivity, and long-term durability. This paper presents the reactor development and performance results at various operating conditions. Additionally, results from 100-hr durability tests and mechanical vibration tests are discussed.

Junaedi, Christian↗
NASA NTRS1964

Problems of Fire Prevention and Extinguishment in Space Cabins

The problems of prevention and extinguishment of fires in space cabins are, except for a few specific situations, not much different from those at sea level or in aircraft conditions. The unusual atmospheric environment and limitations of space and firefighting equipment compound the general problem. The zero-gravity environment modifies firefighting procedures in a rather profound way and will be given detailed treatment in this report.

CHEMICAL EXTINGUISHER↗
NASA NTRS1971

Estimating carbon monoxide exposure

Method predicts effects of carbon monoxide on astronauts confined in spacecraft cabin atmospheres. Information on need for low toxicity level also applies to confined spaces. Benefits are applicable to industry and public health.

Edgerley, R. H.↗
NASA NTRS1981

Beam stresses induced by a turbulent boundary layer and simulated with a reverberant acoustic field

Unsteady pressure fluctuations are a feature of the flow field of an airplane or a space vehicle in atmospheric flight. Undesirable effects of these fluctuations range from internal (cabin) noise to structural fatigue and damage of avionic and ordnance systems. The integrity to withstand these fluctuating loads is established through reverberant room acoustical qualification testing. The purpose of this paper is to develop a methodology of simulating turbulent boundary layer fluctuating pressure loading for a simply supported beam with a reverberant acoustic field. This goal was accomplished using normal mode vibration analysis. The main results were developed in terms of dimensionless quantities such as turbulent boundary layer spectrums, reverberant acoustical field simulation spectrums, and stress response spectrums with parameters: dimensionless fundamental frequency, Mach number, and relative boundary layer displacement thickness.

Schutzenhofer, L. A.↗
NASA NTRS2019

Solid Fuel Ignition and Extinction (SoFIE) Project on ISS

The Solid Fuel Ignition and Extinction (SoFIE) project studies ignition and flammability of solid spacecraft materials (fuels) in practical geometries and realistic atmospheric conditions. It is an experiment insert designed for use within the existing Combustion Integrated Rack (CIR). The CIR chamber provides a level of containment and permits testing at variable oxygen concentrations and pressures representative of current and planned NASA Space Exploration Atmospheres. The applications of SoFIE include: (1) Determining safer selection of cabin materials and validating NASA materials flammability selection using 1-g test protocols for low-gravity fires, (2) Improving understanding of early fire growth behavior, (3) Validating material flammability numerical models, (4) Determining optimal suppression techniques for burning materials by diluents, flow reduction, and venting, (5) Obtaining burning behavior of actual engineering materials planned for spacecraft, (6) Developing corresponding models of microgravity flame spread, flammability, and extinction, and use the results to improve normal gravity combustion models for terrestrial applications. The hardware permits a wide range of solid-material combustion and fire suppression studies. It supports multiple investigations using common infrastructure including sample holders, flow control, test sections, external radiant heaters, igniters, and diagnostics. SoFIE has been developed to meet the requirements of five unique investigations. It is currently being built and slated to begin operations on the ISS in July 2021. Given the general capabilities of the hardware insert, it is intended to be used as a facility for future researchers who can propose to NASA for related solid combustion studies.

Ferkul, Paul↗
NASA NTRS2011

Carbon Dioxide Removal via Passive Thermal Approaches

A paper describes a regenerable approach to separate carbon dioxide from other cabin gases by means of cooling until the carbon dioxide forms carbon dioxide ice on the walls of the physical device. Currently, NASA space vehicles remove carbon dioxide by reaction with lithium hydroxide (LiOH) or by adsorption to an amine, a zeolite, or other sorbent. Use of lithium hydroxide, though reliable and well-understood, requires significant mass for all but the shortest missions in the form of lithium hydroxide pellets, because the reaction of carbon dioxide with lithium hydroxide is essentially irreversible. This approach is regenerable, uses less power than other historical approaches, and it is almost entirely passive, so it is more economical to operate and potentially maintenance- free for long-duration missions. In carbon dioxide removal mode, this approach passes a bone-dry stream of crew cabin atmospheric gas through a metal channel in thermal contact with a radiator. The radiator is pointed to reject thermal loads only to space. Within the channel, the working stream is cooled to the sublimation temperature of carbon dioxide at the prevailing cabin pressure, leading to formation of carbon dioxide ice on the channel walls. After a prescribed time or accumulation of carbon dioxide ice, for regeneration of the device, the channel is closed off from the crew cabin and the carbon dioxide ice is sublimed and either vented to the environment or accumulated for recovery of oxygen in a fully regenerative life support system.

Lawson, Michael↗
NASA NTRS1976

A regenerable CO2 and humidity control system for Shuttle

A regenerable CO2 and humidity control system is presently being developed for potential use on Shuttle as an alternate to the baseline Lithium Hydroxide (LiOH) system. The system utilizes a sorbent material (designated 'HS-C') to adsorb CO2 and water vapor from the cabin atmosphere and desorb the CO2 and water vapor overboard when exposed to a space vacuum. Past development programs concentrated on material development and breadboard system fabrication and testing. The present program calls for the design of a flight prototype system capable of integration into the Shuttle vehicle and the development of major components. This paper will show that a regenerable system utilizing HS-C material trades even with the shuttle LiOH system for the baseline four-man, seven-day mission and offers increased savings up to 448 kg for a seven-man, 30-day mission.

Boehm, A. M.↗
NASA NTRS1977

The development and testing of a regenerable CO2 and humidity control system for Shuttle

A regenerable CO2 and humidity control system is presently being developed for potential use on Shuttle as an alternate to the baseline lithium hydroxide (LiOH) system. The system utilizes a sorbent material (designated 'HS-C') to adsorb CO2 and water vapor from the cabin atmosphere and desorb the CO2 and water vapor overboard when exposed to a space vacuum. Continuous operation is achieved by utilizing two beds which are alternately cycled between adsorption and desorption. This paper presents the significant hardware development and test accomplishments of the past year. A half-size breadboard system utilizing a flight configuration canister was successfully performance tested in simulated Shuttle missions. A vacuum desorption test provided considerable insight into the desorption phenomena and allowed a significant reduction of the Shuttle vacuum duct size. The fabrication and testing of a flight prototype canister and flight prototype vacuum valves have proven the feasibility of these full-size, flight-weight components.

Boehm, A. M.↗
NASA NTRS1979

Flight prototype CO2 and humidity control system

A regenerable CO2 and humidity control system is presently being developed for potential use on shuttle as an alternative to the baseline lithium hydroxide system. The system utilizes a sorbent material (designated HS-C) to adsorb CO2 and the latent heat load from the cabin atmosphere and desorb the CO2 and water vapor overboard when exposed to a space vacuum, thus reducing the overall vehicle heat rejection load. Continuous operation is achieved by utilizing two beds which are alternatively cycled between adsorption and desorption. The HS-C material process was verified. Design concepts for the auxiliary components for the HS-C prototype system were generated. Performance testing verified system effectiveness in controlling CO2 partial pressure and humidity.

Rudy, K. M.↗
NASA NTRS2007

Spacecraft Maximum Allowable Concentrations (SMACs) for C3 to C8 Aliphatic Saturated Aldehydes

Spacecraft maximum allowable concentrations (SMACs) for C3 to C8, straight-chain, aliphatic aldehydes have been previously assessed and have been documented in volume 4 of Spacecraft Maximum Allowable Concentrations for Selected Airborne Contaminants (James, 2000). These aldehydes as well as associated physical properties are shown in Table 1. The C3 to C8 aliphatic aldehydes can enter the habitable compartments and contaminate breathing air of spacecraft by several routes including incomplete oxidation of alcohols in the Environmental Control and Life Support System (ECLSS) air revitalization subsystem, as a byproduct of human metabolism, through materials off-gassing, or during food preparation. These aldehydes have been detected in the atmosphere of manned space vehicles in the past. Analysis performed by NASA of crew cabin air samples from the Russian Mir Space Station revealed the presence of C3 to C8 aldehydes at concentrations peaking at approximately 0.1 mg/cu m.

Langford, Shannon D.↗
NASA NTRS2009

A Design Basis for Spacecraft Cabin Trace Contaminant Control

Successful trace chemical contamination control is one of the components necessary for achieving good cabin atmospheric quality. While employing seemingly simple process technologies, sizing the active contamination control equipment must employ a reliable design basis for the trace chemical load in the cabin atmosphere. A simplified design basis that draws on experience gained from the International Space Station program is presented. The trace chemical contamination control design load refines generation source magnitudes and includes key chemical functional groups representing both engineering and toxicology challenges.

Perry, Jay L.↗
NASA NTRS2010

A Review of International Space Station Habitable Element Equipment Offgassing Characteristics

Crewed spacecraft trace contaminant control employs both passive and active methods to achieve acceptable cabin atmospheric quality. Passive methods include carefully selecting materials of construction, employing clean manufacturing practices, and minimizing systems and payload operational impacts to the cabin environment. Materials selection and manufacturing processes constitute the first level of equipment offgassing control. An element-level equipment offgassing test provides preflight verification that passive controls have been successful. Offgassing test results from multiple International Space Station (ISS) habitable elements and cargo vehicles are summarized and implications for active contamination control equipment design are discussed

Perry, Jay L.↗
NASA NTRS2004

Performance of Off-the-Shelf Technologies for Spacecraft Cabin Atmospheric Major Constituent Monitoring

Monitoring the atmospheric composition of a crewed spacecraft cabin is central to successfully expanding the breadth and depth of first-hand human knowledge and understanding of space. Highly reliable technologies must be identified and developed to monitor atmospheric composition. This will enable crewed space missions that last weeks, months, and eventually years. Atmospheric composition monitoring is a primary component of any environmental control and life support system. Instrumentation employed to monitor atmospheric composition must be inexpensive, simple, and lightweight and provide robust performance. Such a system will ensure an environment that promotes human safety and health, and that the environment can be maintained with a high degree of confidence. Key to this confidence is the capability for any technology to operate autonomously, with little intervention from the crew or mission control personnel. A study has been conducted using technologies that, with further development, may reach these goals.

Tatara, J. D.↗
NASA NTRS2002

The Interaction of Spacecraft Cabin Atmospheric Quality and Water Processing System Performance

Although designed to remove organic contaminants from a variety of waste water streams, the planned U.S.- and present Russian-provided water processing systems onboard the International Space Station (ISS) have capacity limits for some of the more common volatile cleaning solvents used for housekeeping purposes. Using large quantities of volatile cleaning solvents during the ground processing and in-flight operational phases of a crewed spacecraft such as the ISS can lead to significant challenges to the water processing systems. To understand the challenges facing the management of water processing capacity, the relationship between cabin atmospheric quality and humidity condensate loading is presented. This relationship is developed as a tool to determine the cabin atmospheric loading that may compromise water processing system performance. A comparison of cabin atmospheric loading with volatile cleaning solvents from ISS, Mir, and Shuttle are presented to predict acceptable limits to maintain optimal water processing system performance.

Perry, Jay L.↗