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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS2008

Lessons Learned From Atomic Oxygen Interaction With Spacecraft Materials in Low Earth Orbit

There have been five Materials International Space Station Experiment (MISSE) passive experiment carriers (PECs) (MISSE 1-5) to date that have been launched, exposed in space on the exterior of International Space Station (ISS) and then returned to Earth for analysis. An additional four MISSE PECs (MISSE 6A, 6B, 7A, and 7B) are in various stages of completion. The PECs are two-sided suitcase to size sample carriers that are intended to provide information on the effects of the low Earth orbital environment on a wide variety of materials and components. As a result of post retrieval analyses of the retrieved MISSE 2 experiments and numerous prior space experiments, there have been valuable lessons learned and needs identified that are worthy of being documented so that planning, design, and analysis of future space environment experiments can benefit from the experience in order to maximize the knowledge gained. Some of the lessons learned involve the techniques, concepts, and issues associated with measuring atomic oxygen erosion yields. These are presented along with several issues to be considered when designing experiments, such as the uncertainty in mission duration, scattering and contamination effects on results, and the accuracy of measuring atomic oxygen erosion.

Banks, Bruce A.↗
NASA NTRS1991

Oxygen production processes on the Moon: An overview

The production of oxygen on the Moon utilizing indigenous material is paramount to a successful lunar colonization. Several processes were put forth to accomplish this. The lunar liquid oxygen (LLOX) generation schemes which have received the most study to date are those involving: (1) the reduction of ilmenite (FeTiO3) by H2, C, CO, CH4, CO-Cl2 plasma; (2) magma electrolysis, both unadulterated and fluoride-fluxed, and (3) several others, including carbo-chlorination, HF acid leaching, fluorine extraction, magma oxidation, and vapor pyrolysis. The H2 reduction of ilmenite and magma electrolysis processes have received the most study to date. At this stage of development, they both appear feasible schemes with various pros and cons. However, all processes should be addressed at least at the onset of the considerations. It is ultimatley the energy requirements of the entire process, including the acquisition of feedstock, which will determine the mode of oxygen productions. There is an obvious need for considerably more experimentation and study. Some of these requisite studies are in progress, and several of the most studied and feasible processes for winning oxygen from lunar materials are reviewed.

Taylor, Lawrence A.↗
NASA NTRS1996

Meteoritic Sulfur Isotopic Analysis

Funds were requested to continue our program in meteoritic sulfur isotopic analysis. We have recently detected a potential nucleosynthetic sulfur isotopic anomaly. We will search for potential carriers. The documentation of bulk systematics and the possible relation to nebular chemistry and oxygen isotopes will be explored. Analytical techniques for delta(sup 33), delta(sup 34)S, delta(sup 36)S isotopic analysis were improved. Analysis of sub milligram samples is now possible. A possible relation between sulfur isotopes and oxygen was detected, with similar group systematics noted, particularly in the case of aubrites, ureilites and entstatite chondrites. A possible nucleosynthetic excess S-33 has been noted in bulk ureilites and an oldhamite separate from Norton County. High energy proton (approximately 1 GeV) bombardments of iron foils were done to experimentally determine S-33, S-36 spallogenic yields for quantitation of isotopic measurements in iron meteorites. Techniques for measurement of mineral separates were perfected and an analysis program initiated. The systematic behavior of bulk sulfur isotopes will continue to be explored.

Thiemens, Mark H.↗
NASA NTRSDate not supplied

Using Open Standards and NASA Open Source Simulation Tools to Model Artemis Base Camp Mission Timelines

The United States’ National Aeronautics and Space Administration (NASA) has announced that the Artemis Program will return humans to the Moon, establishing a persistent presence with the Artemis Base Camp (ABC), and extend human exploration to Mars. The NASA Exploration Systems Simulations (NExSyS) team at NASA’s Johnson Space Center is using internationally developed simulation interoperability standards and NASA open source simulation tools to support Artemis concept, analysis, designs, development, training, and ultimately operations. The NExSyS team has been tasked to support early ABC architecture and mission analysis using mission time lines developed by the crew operations mission planning team. The NExSyS team is developing a distributed simulation framework with initial Artemis element implementations to model the ABC mission timelines using the international simulation interoperability standard High Level Architecture (HLA), the Simulation Interoperability Standards Organization’s Space Reference Federation Object Model (SpaceFOM), the NASA open source Trick Simulation Environment, and another NASA open source interface package called TrickHLA. The ABC architecture is composed of a number of key surface elements and resources. Some examples of modeled elements (also known as entities) are landers, habitats, rovers, logistics carriers, and astronauts. Some examples of modeled transferable and consumable resources are power, water, oxygen, nitrogen, scientific samples, and food. These entities and resources are modeled in a collection of individual simulations called Federates. A coordinated collection of interoperable federates is called a Federation and when these federates are tied together in a coordinated simulation run, it is referred to as a Federation Execution. The federates communicate through HLA using data exchange formats defined by a collection of machine readable files called Federation Object Models (FOMs). These FOM files are based on extensions to the SpaceFOM. This enables the instantiation and sharing of objects and interactions between federates in the federation. These provide for entity and resource tracking, object transfer, and data collection. Federate interactions are used to trigger events and notify federates of entity or resource transfers. For the initial implementation, the constituent federates are Trick-based simulations that use TrickHLA to provide the required HLA-base interoperability. These Trick-based simulations provide the required modeling for the individual Artemis elements along with the associated element resources. These federates provide a means to explore traverses between surface elements and exploration sites as scheduled in a mission timeline and explore the affects traverse times have on the overall mission timeline. The mission time lines are modeled using a Trick input file event handling capabilities. Each timeline operation is handled as individual simulation events, and triggered based on previous event status, time of operation, and simulated task completions. In addition, the ABC Federation can be used to perform Monte Carlo analysis. The Monte Carlo tool can vary the inputs, timings, and malfunctions to show how various contingencies in the mission can affect the mission timeline.

Keaton Craig Dodd↗
NASA NTRS1990

ECLS resupply for Space Station Freedom

The design of logistics carriers is presented emphasizing the use of cost-effective pressurized and nonpressurized versions to resupply consumable fluids and provide on-orbit support for the Space Station Freedom. The requirements for the Environmental Control and Life Support (ECLS) system include high-pressure oxygen and nitrogen as well as consumables that do not require pressurization. The nominal and contingency requirements are given for logistics carriers designed to support various mission scenarios by resupplying and servicing fluid systems on-orbit. The resulting design overview for the logistics carriers describes the cryogenic-nitrogen storage during launch and operation of the unpressurized version and the flexible payload-support capacity of the pressurized version. The carriers are characterized as lightweight and versatile, and the resupply of cryogenic nitrogen is a flight-proven capability.

Higginbotham, Keith↗
NASA NTRS2006

MISSE PEACE Polymers Atomic Oxygen Erosion Results

Forty-one different polymer samples, collectively called the Polymer Erosion and Contamination Experiment (PEACE) Polymers, have been exposed to the low Earth orbit (LEO) environment on the exterior of the International Space Station (ISS) for nearly 4 years as part of Materials International Space Station Experiment 2 (MISSE 2). The objective of the PEACE Polymers experiment was to determine the atomic oxygen erosion yield of a wide variety of polymeric materials after long term exposure to the space environment. The polymers range from those commonly used for spacecraft applications, such as Teflon (DuPont) FEP, to more recently developed polymers, such as high temperature polyimide PMR (polymerization of monomer reactants). Additional polymers were included to explore erosion yield dependence upon chemical composition. The MISSE PEACE Polymers experiment was flown in MISSE Passive Experiment Carrier 2 (PEC 2), tray 1, on the exterior of the ISS Quest Airlock and was exposed to atomic oxygen along with solar and charged particle radiation. MISSE 2 was successfully retrieved during a space walk on July 30, 2005, during Discovery s STS-114 Return to Flight mission. Details on the specific polymers flown, flight sample fabrication, pre-flight and post-flight characterization techniques, and atomic oxygen fluence calculations are discussed along with a summary of the atomic oxygen erosion yield results. The MISSE 2 PEACE Polymers experiment is unique because it has the widest variety of polymers flown in LEO for a long duration and provides extremely valuable erosion yield data for spacecraft design purposes.

deGroh, Kim, K.↗
NASA NTRS1989

Orienting Superconductive Crystals For High Current Density

Proposed technique for controlled distortion of crystal grains in newly discoverd superconductor YBa2Cu3O7-x increases current-carrying capacity. Helps to ensure grains in this and other anisotropic materials all oriented in same direction so charge carriers transferred readily from one grain to another. Specimen of YBa2Cu3O7-x heated in oxygen atmosphere compressed in one direction as slowly cooled below transition temperature. Under these conditions, oxygen atoms tend to rearrange so as to relieve stress created by compression.

Shlichta, Paul J.↗
NASA NTRS1986

Investigation of porous polymer gas chromatographic packings for atmospheric analysis of extraterrestrial bodies

Measurement of the permanent gases in the atmospheres of mission targets is a major objective. A 16 meter long Porapak N column was used on the Venus probe and required a rather high carrier gas flow rate. The researchers have, therefore, surveyed commercial porous polymer types which had some ability to resolve nitrogen, oxygen, argon and carbon monoxide gases. Porapaks N and Q appeared superior to most. Batch to batch variation, however, was quite wide, so the researchers learned how to synthesize porous polymer and investigated some of the factors affecting the separations. A polymer was synthesized which was superior to all commercial products and allowed at least a 50% reduction in length and flow rate of carrier gas. Similar studies were made concerning the separation of hydrocarbons and new porous polymers have been synthesized which represent significant improvements in time of analysis, column, and carrier gas flow rate.

Pollock, G. E.↗
NASA NTRS1994

Implementation of and measurement with the LIPA technique in a subsonic jet

LIPA (Laser Induced Photochemical Anemometry) was used to measure velocity, vorticity, Reynolds stress, and turbulent intensity distributions in a subsonic jet. The jet region of interest was the area close to the jet-orifice. The LIPA-technique is a nonintrusive quantitative flow visualization technique, consisting of tracking a phosphorescing grid of fluid particles, which is impressed by laser-beams directed into the flow. The phosphorescence of biacetyl gas was used to enable tracking of the impressed light grid. In order to perform measurements in a jet, LIPA was developed and implemented for the specific flow requirements. Nitrogen was used as the carrier gas to avoid quenching of the phosphorescent radiation of the tracer gas biacetyl by ambient oxygen. The use of sulfur dioxide to sensitize phosphorescent emission of biacetyl was examined. Preliminary data was used in a discussion of the potential of the LIPA technique.

Falco, R. E.↗
NASA NTRS1991

Growth and characterization of high-performance photorefractive BaTiO3 crystals

Barium titanate has been used for many nonlinear optical applications primarily because it has high grain and high self-pumped phase conjugate reflectivities. However, barium titanate has had a relatively slow response time, and thus low sensitivity. Therefore, it has not been suited to real-time operations. In this report we will describe the modifications in crystal growth, doping, reduction, and poling that have produced barium titanate crystals with the fastest photorefractive response time reported to date, approximately 21 microseconds with a beam-coupling gain coefficient of 38.7 cm(exp -1) and the highest sensitivity reported to date of 3.44 cm(exp 3)/kJ. The sensitivity of these barium titanate crystals is comparable to or greater than other photorefractive oxides. We will show, for the first time, beam-coupling in barium titanate at video frame rates. We infer from response time measurements that barium titanate has a phonon limited mobility. Also, photorefractive response time measurements as a function of the crystallographic orientation and grating wave vector for our cobalt-doped oxygen reduced crystals indicate that their faster response time arise because of an increase in the free carrier lifetime.

Warde, C.↗
NASA NTRS2000

Dynamics of Molecular Hydrogen in Hypersaline Microbial Mars

Early Earth microbial communities that centered around the anaerobic decomposition of organic molecular hydrogen as a carrier of electrons, regulator of energy metabolism, and facilitator of syntroph'c microbial interactions. The advent of oxygenic photosynthetic organisms added a highly dynamic and potentially dominant term to the hydrogen economy of these communities. We have examined the daily variations of hydrogen concentrations in cyanobacteria-dominated microbial mats from hypersaline ponds in Baja California Sur, Mexico. These mats bring together phototrophic and anaerobic bacteria (along with virtually all other trophic groups) in a spatially ordered and chemically dynamic matrix that provides a good analog for early Earth microbial ecosystems. Hydrogen concentrations in the photic zone of the mat can be three orders of magnitude or more higher than in the photic zone, which are, in turn, an order of magnitude higher than in the unconsolidated sediments underlying the mat community. Within the photic zone, hydrogen concentrations can fluctuate dramatically during the diel (24 hour day-night) cycle, ranging from less than 0.001% during the day to nearly 10% at night. The resultant nighttime flux of hydrogen from the mat to the environment was up to 17% of the daytime oxygen flux. The daily pattern observed is highly dependent on cyanobacterial species composition within the mat, with Lyngbya-dominated systems having a much greater dynamic range than those dominated by Microcoleus; this may relate largely to differing degrees of nitrogen-fixing and fermentative activity in the two mats. The greatest H2 concentrations and fluxes were observed in the absence of oxygen, suggesting an important potential feedback control in the context of the evolution of atmospheric composition. The impact of adding this highly dynamic photosynthetic term to the hydrogen economy of early microbial ecosystems must have been substantial. From an evolutionary standpoint, the H2 generated in mats could have represented a very important new source of electrons and energy - but one that could not be harnessed without substantial adaptation to the highly variable chemistry of the mat surface. In addition, the emergent chemistry of anaerobic communities is often highly dependent on ambient hydrogen concentrations, so that incorporation of these communities into photosynthetic mats could have significantly affected the composition and flux of reduced "biosignature' gases to the environment.

Hoehler, Tori M.↗
NASA NTRS1990

Steady-state analysis of a nonlinear rotor-housing system

The periodic steady state response of a high pressure oxygen turbopump (HBOTP) of a Space Shuttle main engine (SSME), involving a clearance between the bearing and housing carrier, is sought. A harmonic balance method utilizig Fast Fourier Transform (FFT) algorithm is developed for the analysis. An impedance method is used to reduce the number of degrees of freedom to the displacements at the bearing clearance. Harmonic and subharmonic responses to imbalance for various system parameters are studied. The results show that the computational technique developed in this study is an effective and flexible method for determining the stable and unstable periodic response of complex rotor-housing systems with clearance type nonlinearity.

Noah, S. T.↗
NASA NTRS1992

STS-46 Space Shuttle mission report

The STS-46 Space Shuttle Program Mission Report contains a summary of the Orbiter, External Tank (ET), Solid Rocket Booster/Redesigned Solid Rocket Motor (SRB/RSRM), and the Space Shuttle main engine (SSME) subsystem performance during the forty-ninth flight of the Space Shuttle Program, and the twelfth flight of the Orbiter vehicle Atlantis (OV-104). In addition to the Atlantis vehicle, the flight vehicle consisted of the following: an ET, designated ET-48 (LWT-41); three SSME's, which were serial numbers 2032, 2033, and 2027 in positions 1, 2, and 3, respectively; and two SRB's which were designated BI-052. The lightweight/redesigned SRM's that were installed in each SRB were designated 360W025A for the left RSRM and 360L025B for the right RSRM. The primary objective of this flight was to successfully deploy the European Retrievable Carrier (EURECA) payload and perform the operations of the Tethered Satellite System-1 (TSS-1) and the Evaluation of Oxygen Interaction with Material 3/Thermal Energy Management Processes 2A-3 (EOIM-3/TEMP 2A-3). The secondary objectives of this flight were to perform the operations of the IMAX Cargo Bay Camera (ICBC), Consortium for Material Development in Space Complex Autonomous Payload-2 and 3 (CONCAP-2 and CONCAP-3), Limited Duration Space Environment Candidate Materials Exposure (LDCE), Pituitary Growth Hormone Cell Function (PHCF), and Ultraviolet Plume Instrumentation (UVPI). In addition to summarizing subsystem performance, this report also discusses each Orbiter, ET, SSME, SRB, and RSRM in-flight anomaly in the applicable section of the report. Also included in the discussion is a reference to the assigned tracking number as published on the Problem Tracking List. All times are given in Greenwich mean time (G.m.t.) as well as mission elapsed time (MET).

Fricke, Robert W.↗
NASA NTRS1989

Controlled-Turbulence Bioreactors

Two versions of bioreactor vessel provide steady supplies of oxygen and nutrients with little turbulence. Suspends cells in environment needed for sustenance and growth, while inflicting less damage from agitation and bubbling than do propeller-stirred reactors. Gentle environments in new reactors well suited to delicate mammalian cells. One reactor kept human kidney cells alive for as long as 11 days. Cells grow on carrier beads suspended in liquid culture medium that fills cylindrical housing. Rotating vanes - inside vessel but outside filter - gently circulates nutrient medium. Vessel stationary; magnetic clutch drives filter cylinder and vanes. Another reactor creates even less turbulence. Oxygen-permeable tubing wrapped around rod extending along central axis. Small external pump feeds oxygen to tubing through rotary coupling, and oxygen diffuses into liquid medium.

Wolf, David A.↗
NASA NTRS1993

Consortium for materials development in space

During fiscal 1993, the Consortium for Materials Development in Space (CMDS) maintained the organizational structure and project orientation established in prior years. The commercial objectives are improved materials, biomedical applications, and infrastructure and support hardware. Projects include nonlinear optical materials; space materials (specifically polymer foam/films, atomic oxygen and high temperature superconductors); alloyed and blended materials: sintered and alloyed materials; polymer and carbonate blends; electrodeposition; organic separation; materials dispersion and biodynamics; space carriers: Consort, COMET support, Spacehab utilization; and flight services: accelerometers, CMIX, USEC, ORSEP, and Space Experiment Facility (SEF).

Source record↗
NASA NTRS2015

Insulation Resistance Degradation in Ni-BaTiO3 Multilayer Ceramic Capacitors

Insulation resistance (IR) degradation in NiBaTiO3 multilayer ceramic capacitors has been characterized by the measurement of both time to failure (TTF) and direct current leakage current as a function of stress time under highly accelerated life test conditions. The measured leakage current time dependence data fit well to an exponential form, and a characteristic growth time tau (sub SD) can be determined. A greater value of tau (sub SD) represents a slower IR degradation process. Oxygen vacancy migration and localization at the grain boundary region results in the reduction of the Schottky barrier height and has been found to be the main reason for IR degradation in NiBaTiO3 capacitors. The reduction of barrier height as a function oftime follows an exponential relation of phi (t ) = phi (0) e (exp -2Kt), where 13 the degradation rate constant K Koe (Ek/kT) is inversely proportional to the mean TTF (MTTF) and can be determined using an Arrhenius plot. For oxygen vacancy electromigration, a lower barrier height phi (0) will favor a slow IR degradation process, but a lower phi (0) will also promote electronic carrier conduction across the barrier and decrease the IR. As a result, a moderate barrier height phi (0) (and therefore a moderate IR value) with a longer MTTF (smaller degradation rate constant K) will result in a minimized IR degradation process and the most improved reliability in NiBaTiO3 multilayer ceramic capacitors.

reliability↗
NASA NTRS2015

Insulation Resistance Degradation in Ni-BaTiO3 Multilayer Ceramic Capacitors

Insulation resistance (IR) degradation in Ni-BaTiO3 multilayer ceramic capacitors has been characterized by the measurement of both time to failure and direct-current (DC) leakage current as a function of stress time under highly accelerated life test conditions. The measured leakage current-time dependence data fit well to an exponential form, and a characteristic growth time SD can be determined. A greater value of tau(sub SD) represents a slower IR degradation process. Oxygen vacancy migration and localization at the grain boundary region results in the reduction of the Schottky barrier height and has been found to be the main reason for IR degradation in Ni-BaTiO3 capacitors. The reduction of barrier height as a function of time follows an exponential relation of phi (𝑡)=phi (0)e(exp -2Κt), where the degradation rate constant 𝐾=𝐾o𝑒(𝐸𝑘/𝑘𝑇) is inversely proportional to the mean time to failure (MTTF) and can be determined using an Arrhenius plot. For oxygen vacancy electromigration, a lower barrier height phi(0) will favor a slow IR degradation process, but a lower phi(0) will also promote electronic carrier conduction across the barrier and decrease the insulation resistance. As a result, a moderate barrier height phi(0) (and therefore a moderate IR value) with a longer MTTF (smaller degradation rate constant 𝐾) will result in a minimized IR degradation process and the most improved reliability in Ni-BaTiO3 multilayer ceramic capacitors.

dielectric degradation↗