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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 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

Space Shuttle life support systems - A status report

The Space Shuttle Program has two independent life support systems. One provides the basic environmental control for the Orbiter cabin while the second enables the crewmen to function outside the spacecraft for extravehicular operation. Although both of these systems were developed and fabricated under contract to NASA, all system-level testing was conducted at the Johnson Space Center. The paper will discuss the results of this testing which, in part, includes: (1) certification of the Orbiter cabin atmospheric pressure and composition control system at three operational pressures (8 psia, 9 psia and 14.7 psia); (2) certification of the Orbiter atmospheric revitalization system at 9 psia and 14.7 psia; (3) manrating of the Orbiter airlock at 14.7 psia, 9 psia and vacuum; and (4) certification of the space suit/life support system in the airlock and at deep space thermal/vacuum conditions. In addition, pertinent flight information from the on-orbit performance of the Shuttle life support systems will be presented.

Faget, M. A.↗
NASA NTRS1983

A computer simulation of aircraft evacuation with fire

A computer simulation was developed to assess passenger survival during the post-crash evacuation of a transport category aircraft when fire is a major threat. The computer code, FIREVAC, computes individual passenger exit paths and times to exit, taking into account delays and congestion caused by the interaction among the passengers and changing cabin conditions. Simple models for the physiological effects of the toxic cabin atmosphere are included with provision for including more sophisticated models as they become available. Both wide-body and standard-body aircraft may be simulated. Passenger characteristics are assigned stochastically from experimentally derived distributions. Results of simulations of evacuation trials and hypothetical evacuations under fire conditions are presented.

Middleton, V. E.↗
NASA NTRS1982

A regenerable solid amine CO2 concentrator for space station

A regenerable solid amine CO2 control system, which employs water vapor for desorption, is being developed for potential use on long duration space missions. During cyclic operation, CO2 is first absorbed from the cabin atmosphere onto the granular amine. Steam is then used to heat the solid amine bed and desorb the CO2. This paper describes the solid amine system operation and application to the Shuttle Orbiter, Manned Space Platform (MSP) and Space Operations Center (SOC). The importance and interplay of system performance parameters are presented together with supporting data and design characteristics.

Boehm, A. M.↗
NASA NTRS1983

Biomedical results of the Space Shuttle orbital flight test program

On July 4, 1982, the Space Shuttle Columbia landed at Edwards Air Force Base, CA, thus successfully completing the fourth and last in a series of Orbital Flight Tests (OFT) of the Space Transportation System (STS). The primary goal of medical operations support for the OFT was to assure the health and well-being of flight personnel during all phases of the mission. To this end, crew health status was evaluated preflight, inflight, and postflight. Biomedical flight test requirements were completed in the following areas: physiological adaptation to microgravity, cabin acoustical noise, cabin atmospheric evaluation, radiation dosimetry, crew exercise equipment evaluation, and a cardiovascular deconditioning countermeasure assessment.

Pool, S. L.↗
NASA NTRS1983

Toxicological evaluation of the Columbia spacecraft

The toxicology procedures developed for the Space Shuttle program to evaluate and eliminate contaminants in the cabin atmosphere characterized, and results from STS missions 1-5 are reviewed. Shuttle maximum-allowable-concentration standards (SMAC) equal to 10-50 percent of those established for normal 40-h work weeks on the ground have been established for a broad range of substances, and outgassing data are employed in choosing spacecraft construction materials. Gases are removed by the atmospheric revitalization system (CO2-removal bed, catalytic oxidizer, and dehumidifier). Whole-gas and adsorbed-gas samples are employed in ground-based and inflight measurements of contaminants: results are presented in tables. A total of 152 substances, of which 64 were well defined, were detected in STS-1-5. Only the toluene contamination on STS-2 (17 ppm compared to the SMAC of 20 ppm) was considered serious.

Rippstein, W. J., Jr.↗
NASA NTRS1985

Extended mission life support systems

Extended manned space missions which include interplanetary missions require regenerative life support systems. Manned mission life support considerations are placed in perspective and previous manned space life support system technology, activities and accomplishments in current supporting research and technology (SR&T) programs are reviewed. The life support subsystem/system technologies required for an enhanced duration orbiter (EDO) and a space operations center (SOC), regenerative life support functions and technology required for manned interplanetary flight vehicles, and future development requirements are outlined. The Space Shuttle Orbiters (space transportation system) is space cabin atmosphere is maintained at Earth ambient pressure of 14.7 psia (20% O2 and 80% N2). The early Shuttle flights will be seven-day flights, and the life support system flight hardware will still utilize expendables.

Quattrone, P. D.↗
NASA NTRS1987

Stability of IRA-45 solid amine resin as a function of carbon dioxide absorption and steam desorption cycling

The removal of CO2 from the NASA Space Station's cabin atmosphere, which may be undertaken by a solid-amine water (steam)-desorbed system, is presently evaluated with a view to long-term amine resin stability and adsorption/desorption cycling by means of an automated laboratory flow-testing facility. While the CO2-adsorption capacity of the IRA-45 amine resin used gradually decreased over time, the rate of degradation significantly decreased after the first 10 cycles. Attention is given to the presence (and possible need for removal) of trimethylamine in the process air downstream of the resin bed.

Wood, Peter C.↗
NASA NTRS1988

Oxygen sensor optimization for long duration space missions

A new type of oxygen sensor is being developed for potential use in future manned space missions. This sensor incorporates two independent measurement schemes using dual electrochemical cells formed in a common body of solid electrolyte-zirconia. A combination of potentiometric and coulometric measurements yields accurate and fast response to cabin atmosphere oxygen. Means for self-calibration, fault detection and diagnosis by computer operation are discussed.

Taylor, R. M.↗
NASA NTRS1991

Benefits from synergies and advanced technologies for an advanced-technology space station

A configuration for a second-generation advanced technology space station has been defined in a series of NASA-sponsored studies. Definitions of subsystems specifically addressed opportunities for beneficial synergistic interactions and those potential synergies and their benefits are identified. One of the more significant synergistic benefits involves the multi-function utilization of water within a large system that generates artificial gravity by rotation. In such a system, water not only provides the necessary crew life support, but also serves as counterrotator mass, as moveable ballast, and as a source for propellant gases. Additionally, the synergistic effects between advanced technology materials, operation at reduced artificial gravity, and lower cabin atmospheric pressure levels show beneficial interactions that can be quantified in terms of reduced mass to orbit.

Garrett, L. Bernard↗
NASA NTRS1990

The Extended Duration Orbiter Regenerable CO2 Removal System

A new carbon dioxide scrubber system is undergoing development for extended duration orbiter (EDO) missions. The EDO requirements of missions up to 18 days and the capability for future missions up to 30 days necessitated the development and implementation of a regenerative CO2 removal process. This new system will reduce the launch weight and stowage volume as compared to the present method of CO2 removal, lithium hydroxide, which is stowed in canisters. The selected design, called the Regenerable CO2 Removal System (RCRS), uses a solid amine material to adsorb carbon dioxide and water vapor and periodically desorb these to space vacuum. The RCRS, which is located below the middeck floor, interfaces with the orbiter's cabin Atmospheric Revitalization System and is adjustable from four to seven crewmembers. The RCRS is designed to automatically cycle the beds from absorb to vacuum-desorb every 30 minutes. Also incorporated into the design are features such consumable recovery, external leak protection, trace contaminant control and automatic control logic operation.

Ouellette, Fred A.↗
NASA NTRS1990

Preliminary evaluation of a membrane-based system for removing CO2 from air

Processes to remove and/or recover CO2 from air are essential to the long-term success of the U.S. space program. The results of a preliminary investigation of the use of a novel membrane-based system for removal of CO2 from air are presented. Features of this technology that make it attractive include the following: (1) it is lightweight; (2) it requires no consumables or expendables; (3) it is relatively simple; and (4) it does not rely directly on other subsystems. Preliminary designs of systems for removing CO2 from spacecraft cabin atmospheres and from the extravehicular mobility unit are presented.

Mccray, Scott B.↗
NASA NTRS1992

A review of microgravity surgical investigations

The likelihood of performing a surgical procedure in space will increase as the Soviet Mir space station is expanded and the Space Station Freedom becomes operational. A review of previous research and hardware development, performed mostly in parabolic flight both in the Soviet Union and the U.S., reveals an interest in surgical chambers to prevent cabin atmosphere contamination. Surgical techniques appear to be no more difficult than in a 1-G environment if a restraint system is used. Minimizing the changes of wound infection from the high particle count spacecraft atmosphere is an additional concern. Additional research is necessary to delineate the clinical significance of these problems and to further develop surgical techniques in microgravity.

Campbell, Mark R.↗
NASA NTRS1993

Toxicokinetics of inhaled bromotrifluoromethane (Halon 1301) in human subjects

Bromotrifluoromethane (Halon 1301, CBrF3), is used as a fire extinguishant in the Space Shuttle, where several scenarios, such as a fire or a faulty alarm, could lead to its discharge resulting in a Halon 1301 concentration of up to 1 percent in the cabin atmosphere. The effect of Halon 1301 on mental performance and physiologic function was investigated in a NASA-sponsored human inhalation study in which four pairs of male subjects were each exposed in a double-blind fashion for 24 hr to 1 percent Halon 1301 and to air in two exposures about 1 week apart. Blood and breath samples from the exposed subjects were collected to provide dosimetric and toxicokinetic information. Halon 1301 blood levels increased rapidly and approached a steady state within 2 hr of the beginning the exposure; the steady-state concentration was approximately 3-4.5 microg/ml. Breath samples collected during exposures closely reflected chamber concentrations. Analysis of postexposure blood samples revealed that Halon 1301 was eliminated biphasically with an average t(1/2) alpha and t(1/2) beta of 4.5 min and 200 min, respectively.

Lam, C. W.↗
NASA NTRS1992

Operation of a breadboard liquid-sorbent/membrane-contactor system for removing carbon dioxide and water vapor from air

Processes to remove and recover carbon dioxide (CO2) and water vapor from air are essential for successful long-duration space missions. This paper presents results of a developmental program focused on the use of a liquid-sorbent/membrane-contactor (LSMC) system for removal of CO2 and water vapor from air. In this system, air from the spacecraft cabin atmosphere is circulated through one side of a hollow-fiber membrane contactor. On the other side of the membrane contactor is flowed a liquid sorbent, which absorbs the CO2 and water vapor from the feed air. The liquid sorbent is then heated to desorb the CO2 and water vapor. The CO2 is subsequently removed from the system as a concentrated gas stream, whereas the water vapor is condensed, producing a water stream. A breadboard system based on this technology was designed and constructed. Tests showed that the LSMC breadboard system can produce a CO2 stream and a liquid-water stream. Details are presented on the operation of the system, as well as the effects on performance of variations in feed conditions.

Mccray, Scott B.↗
NASA NTRS1993

A combustion products analyzer for contingency use during thermodegradation events on spacecraft

The Toxicology Laboratory at JSC and Exidyne Instrumentation Technologies (EIT) have developed a prototype Combustion Products Analyzer (CPA) to monitor, in real time, combustion products from a thermodegradation event on board spacecraft. The CPA monitors the four gases that are the most hazardous compounds (based on the toxicity potential and quantity produced) likely to be released during thermodegradation of synthetic materials: hydrogen fluoride (HF), hydrogen chloride (HCl), hydrogen cyanide (HCN), and carbon monoxide (CO). The levels of these compounds serve as markers to assist toxicologists in determining when the cabin atmosphere is safe for the crew to breathe following the contingency event. The CPA is a hand-held, battery-operated instrument containing four electrochemical sensors, one for each target gas, and a pump for drawing air across the sensors. The sensors are unique in their small size and zero-g compatibility. The immobilized electrolytes in each sensor permit the instrument to function in space and eliminate the possibility of electrolye leaks. The sample inlet system is equipped with a particulate filter that prevents clogging from airborne particulate matter. The CPA has a large digital display for gas concentrations and warming signals for low flow and low battery conditions. The CPA has flown on 13 missions beginning with STS 41 in Oct. 1990. Current efforts include the development of a microprocessor, an improved carbon monoxide sensor, and a ground-based test program to evaluate the CPA during actual thermodegradation of selected materials.

Wilson, Steve↗
NASA NTRS1994

A users' guide to the trace contaminant control simulation computer program

The Trace Contaminant Control Simulation computer program is a tool for assessing the performance of various trace contaminant control technologies for removing trace chemical contamination from a spacecraft cabin atmosphere. The results obtained from the program can be useful in assessing different technology combinations, system sizing, system location with respect to other life support systems, and the overall life cycle economics of a trace contaminant control system. The user's manual is extracted in its entirety from NASA TM-108409 to provide a stand-alone reference for using any version of the program. The first publication of the manual as part of TM-108409 also included a detailed listing of version 8.0 of the program. As changes to the code were necessary, it became apparent that the user's manual should be separate from the computer code documentation and be general enough to provide guidance in using any version of the program. Provided in the guide are tips for input file preparation, general program execution, and output file manipulation. Information concerning source code listings of the latest version of the computer program may be obtained by contacting the author.

Perry, J. L.↗
NASA NTRS1992

A surgical support system for Space Station Freedom

Surgical techniques in microgravity are being developed for the Health Maintenance Facility (HMF) on Space Station Freedom (SSF). This will be a presentation of the proposed surgical capabilities and ongoing hardware and procedural investigations. Methods: Procedures and prototype hardware, which include a medical restraint system, a surgical overhead isolation canopy, a suction device, and a regional laminar flow device were evaluated. This was accomplished by realistic sterile surgical simulations involving both mannequins and animals during KC-135 parabolic flight and in a high fidelity ground based HMF mockup. Results: Animal surgery in the environment of microgravity allowed the observation of unique arterial and venous bleeding characteristics for the first time. The ability to control bleeding and to prevent cabin atmosphere contamination was also demonstrated. Conclusions: The procedures and prototype hardware tested provided valuable information and should be investigated and developed further. The use of standard surgical techniques are possible in microgravity if the principles of personnel and supply restraint and operative field containment are adhered to.

Campbell, M. R.↗
NASA NTRS1995

Trace chemical contaminant generation rates for spacecraft contamination control system design

A spacecraft presents a unique design challenge with respect to providing a comfortable environment in which people can live and work. All aspects of the spacecraft environmental design including the size of the habitable volume, its temperature, relative humidity, and composition must be considered to ensure the comfort and health of the occupants. The crew members and the materials selected for outfitting the spacecraft play an integral part in designing a habitable spacecraft because material offgassing and human metabolism are the primary sources for continuous trace chemical contaminant generation onboard a spacecraft. Since these contamination sources cannot be completely eliminated, active control processes must be designed and deployed onboard the spacecraft to ensure an acceptably clean cabin atmosphere. Knowledge of the expected rates at which contaminants are generated is very important to the design of these processes. Data from past spacecraft missions and human contaminant production studies have been analyzed to provide this knowledge. The resulting compilation of contaminants and generation rates serve as a firm basis for past, present, and future contamination control system designs for space and aeronautics applications.

Perry, J. L.↗