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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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NASA NTRS2004

Waste Processing Research and Technology Development at NASA Ames Research Center

The current "store and return" approach for handling waste products generated during low Earth orbit missions will not meet the requirements for future human missions identified in NASA s new Exploration vision. The objective is to develop appropriate reliable waste management systems that minimize maintenance and crew time, while maintaining crew health and safety, as well as providing protection of planetary surfaces. Solid waste management requirements for these missions include waste volume reduction, stabilization and storage, water recovery, and ultimately recovery of carbon dioxide, nutrients and other resources from a fully regenerative food production life support system. This paper identifies the key drivers for waste management technology development within NASA, and provides a roadmap for the developmental sequence and progression of technologies. Recent results of research and technology development activities at NASA Ames Research Center on candidate waste management technologies with emphasis on compaction, lyophilization, and incineration are discussed.

Fisher, John↗

NASA NTRS2007

North American Vegetation Dynamics Observed with Multi-Resolution Satellite Data

North American vegetation has been discovered to be a net carbon sink, with atypical behavior of drawing down more carbon from the atmosphere during the past century. It has been suggested that the Northern Hemisphere will respond favorably to climate warming by enhancing productivity and reducing the impact of fossil fuel emissions into the atmosphere. Many investigations are currently underway to understand and identify mechanisms of storage so they might be actively managed to offset carbon emissions which have detrimental consequences to the functioning of ecosystems and human well being. This paper used a time series of satellite data from multiple sensors at multiple resolutions over the past thlrty years to identify and understand mechanisms of change to vegetation productivity throughout North America. We found that humans had a marked impact to vegetation growth in half of the six selected study regions which cover greater than two million km2. We found climatic influences of increasing temperatures, and longer growing seasons with reduced snow cover in the northern regions of North America with forest fire recovery in the Northern coniferous forests of Canada. The Mid-latitudes had more direct land cover changes induced by humans coupled with climatic influences such as severe drought and altered production strategies of rain-fed agriculture in the upper Midwest, expansion of irrigated agriculture in the lower Midwest, and insect outbreaks followed by subsequent logging in the upper Northeast. Vegetation growth over long time periods (20+ years) in North America appears to be associated with long term climate change but most of the marked changes appear to be associated with climate variability on decadal and shorter time scales along with direct human land cover conversions. Our results document regional land cover land use change and climatic influences that have altered continental scale vegetation dynamics in North America.

Neigh, Christopher S. R.↗

NASA NTRS2008

Kinetic Temperature and Carbon Dioxide from Broadband Infrared Limb Emission Measurements Taken from the TIMED/SABER Instrument

The Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) experiment is one of four instruments on NASA's Thermosphere-Ionosphere-Energetics and Dynamics (TIMED) satellite. SABER measures broadband infrared limb emission and derives vertical profiles of kinetic temperature (Tk) from the lower stratosphere to approximately 120 km, and vertical profiles of carbon dioxide (CO2) volume mixing ratio (vmr) from approximately 70 km to 120 km. In this paper we report on SABER Tk/CO2 data in the mesosphere and lower thermosphere (MLT) region from the version 1.06 dataset. The continuous SABER measurements provide an excellent dataset to understand the evolution and mechanisms responsible for the global two-level structure of the mesopause altitude. SABER MLT Tk comparisons with ground-based sodium lidar and rocket falling sphere Tk measurements are generally in good agreement. However, SABER CO2 data differs significantly from TIME-GCM model simulations. Indirect CO2 validation through SABER-lidar MLT Tk comparisons and SABER-radiation transfer comparisons of nighttime 4.3 micron limb emission suggest the SABER-derived CO2 data is a better representation of the true atmospheric MLT CO2 abundance compared to model simulations of CO2 vmr.

Mertens, Christopher J.↗

NASA NTRS2007

Correction to "Energy Transport in the Thermosphere During the Solar Storms of April 2002"

We present corrected computations of the infrared power and energy radiated by nitric oxide (NO) and carbon dioxide (CO2) during the solar storm event of April 2002. The computations in our previous paper underestimated the radiated power due to improper weighting of the radiated power and energy with respect to area as a function of latitude. We now find that the radiation by NO during the April 2002 storm period accounts for 50% of the estimated energy input to the atmosphere from the solar storm. The prior estimate was 28.5%. Emission computed for CO2 is also correspondingly increased, but the relative roles of CO2 and NO remain unchanged. NO emission enhancement is still, far and away, the dominant infrared response to the solar storms of April 2002.

Mlynczak, Martin G.↗

NASA NTRS2007

Performance of Low Temperature Electrolytes in Experimental and Prototype Li-Ion Cells

Due to their attractive properties and proven success, Li-ion batteries have become identified as the battery chemistry of choice for a number of future NASA missions. A number of these applications would be greatly benefited by improved performance of Li-ion technology over a wider operating temperature range, especially at low temperatures, such as future ESMD missions. In many cases, these technology improvements may be mission enabling, and at the very least mission enhancing. In addition to aerospace applications, the DoE has interest in developing advanced Li-ion batteries that can operate over a wide temperature range to enable terrestrial HEV applications. Thus, our focus at JPL in recent years has been to extend the operating temperature range of Li-ion batteries, especially at low temperatures. To accomplish this, the main focus of the research has been devoted to developing improved lithium-ion conducting electrolytes. In the present paper, we would like to present some of the results we have obtained with ethylene carbonate-based electrolytes optimized for low temperature in experimental MCMB-LiNixCo1_x0 2 cells. In addition to obtaining discharge and charge rate performance data at various temperatures, electrochemical measurements were performed on individual electrodes (made possible by the incorporation of Li reference electrodes), including EIS, linear polarization and Tafel polarization measurements. The combination of techniques enables the elucidation of various trends associated with electrolyte composition. In addition to investigating the behavior in experimental cells, the performance of many promising low temperature electrolytes was demonstrated in large capacity, aerospace quality Li-ion prototype cells. These cells were subjected to a number of performance tests, including discharge rate characterization, charge rate characterization, cycle life performance at various temperatures, and power characterization tests.

Li-ion batteries↗

NASA NTRS2012

Alternative Water Processor Test Development

The Next Generation Life Support Project is developing an Alternative Water Processor (AWP) as a candidate water recovery system for long duration exploration missions. The AWP consists of biological water processor (BWP) integrated with a forward osmosis secondary treatment system (FOST). The basis of the BWP is a membrane aerated biological reactor (MABR), developed in concert with Texas Tech University. Bacteria located within the MABR metabolize organic material in wastewater, converting approximately 90% of the total organic carbon to carbon dioxide. In addition, bacteria convert a portion of the ammonia-nitrogen present in the wastewater to nitrogen gas, through a combination of nitrogen and denitrification. The effluent from the BWP system is low in organic contaminants, but high in total dissolved solids. The FOST system, integrated downstream of the BWP, removes dissolved solids through a combination of concentration-driven forward osmosis and pressure driven reverse osmosis. The integrated system is expected to produce water with a total organic carbon less than 50 mg/l and dissolved solids that meet potable water requirements for spaceflight. This paper describes the test definition, the design of the BWP and FOST subsystems, and plans for integrated testing.

Pickering, Karen D.↗

NASA NTRS2013

Alternative Water Processor Test Development

The Next Generation Life Support Project is developing an Alternative Water Processor (AWP) as a candidate water recovery system for long duration exploration missions. The AWP consists of biological water processor (BWP) integrated with a forward osmosis secondary treatment system (FOST). The basis of the BWP is a membrane aerated biological reactor (MABR), developed in concert with Texas Tech University. Bacteria located within the MABR metabolize organic material in wastewater, converting approximately 90% of the total organic carbon to carbon dioxide. In addition, bacteria convert a portion of the ammonia-nitrogen present in the wastewater to nitrogen gas, through a combination of nitrification and denitrification. The effluent from the BWP system is low in organic contaminants, but high in total dissolved solids. The FOST system, integrated downstream of the BWP, removes dissolved solids through a combination of concentration-driven forward osmosis and pressure driven reverse osmosis. The integrated system is expected to produce water with a total organic carbon less than 50 mg/l and dissolved solids that meet potable water requirements for spaceflight. This paper describes the test definition, the design of the BWP and FOST subsystems, and plans for integrated testing.

Pickering, Karen D.↗

NASA NTRS2010

Carbon Nanotube-Based Digital Vacuum Electronics and Miniature Instrumentation for Space Exploration

JPL has developed high performance cold cathodes using arrays of carbon nanotube bundles that produce > 15 A/sq cm at applied fields of 5 to 8 V/micron without any beam focusing. They have exhibited robust operation in poor vacuums of 10(exp -6) to 10(exp -4) Torr- a typically achievable range inside hermetically sealed microcavities. Using these CNT cathodes JPL has developed miniature X-ray tubes capable of delivering sufficient photon flux at acceleration voltages of <20kV to perform definitive mineralogy on planetary surfaces; mass ionizers that offer two orders of magnitude power savings, and S/N ratio better by a factor of five over conventional ionizers. JPL has also developed a new class of programmable logic gates using CNT vacuum electronics potentially for Venus in situ missions and defense applications. These digital vacuum electronic devices are inherently high-temperature tolerant and radiation insensitive. Device design, fabrication and DC switching operation at temperatures up to 700 C are presented in this paper.

Carbon Nanotube↗

DOE OSTI2020

Impact of methane and black carbon mitigation on forcing and temperature: a multi-model scenario analysis

The relatively short atmospheric lifetimes of methane (CH 4 ) and black carbon (BC) have focused attention on the potential for reducing anthropogenic climate change by reducing Short-Lived Climate Forcer (SLCF) emissions. This paper examines radiative forcing and global mean temperature results from the Energy Modeling Forum (EMF)-30 multi-model suite of scenarios addressing CH 4 and BC mitigation, the two major short-lived climate forcers. Central estimates of temperature reductions in 2040 from an idealized scenario focused on reductions in methane and black carbon emissions ranged from 0.18–0.26 °C across the nine participating models. Reductions in methane emissions drive 60% or more of these temperature reductions by 2040, although the methane impact also depends on auxiliary reductions that depend on the economic structure of the model. Climate model parameter uncertainty has a large impact on results, with SLCF reductions resulting in as much as 0.3–0.7 °C by 2040. We find that the substantial overlap between a SLCF-focused policy and a stringent and comprehensive climate policy that reduces greenhouse gas emissions means that additional SLCF emission reductions result in, at most, a small additional benefit of ~ 0.1 °C in the 2030–2040 time frame.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2022

Improving future travel demand projections: a pathway with an open science interdisciplinary approach

Transport accounts for 24% of global CO 2 emissions from fossil fuels. Governments face challenges in developing feasible and equitable mitigation strategies to reduce energy consumption and manage the transition to low-carbon transport systems. To meet the local and global transport emission reduction targets, policymakers need more realistic/sophisticated future projections of transport demand to better understand the speed and depth of the actions required to mitigate greenhouse gas emissions. In this paper, we argue that the lack of access to high-quality data on the current and historical travel demand and interdisciplinary research hinders transport planning and sustainable transitions toward low-carbon transport futures. We call for a greater interdisciplinary collaboration agenda across open data, data science, behaviour modelling, and policy analysis. These advancemets can reduce some of the major uncertainties and contribute to evidence-based solutions toward improving the sustainability performance of future transport systems. The paper also points to some needed efforts and directions to provide robust insights to policymakers. We provide examples of how these efforts could benefit from the International Transport Energy Modeling Open Data project and open science interdisciplinary collaborations.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

NASA NTRS2014

Aircraft Trajectory Design Based on Reducing the Combined Effects of Carbon-di-oxide, Nitrogen and Contrails

Aircraft operations need to meet the combined requirements of safety, efficiency, capacity and reduced environmental impact. Aircraft routes can be made efficient by flying wind optimal routes. However, the desire to reduce the impact of aviation emissions and contrails may result in trajectories, which deviate from wind optimal trajectories leading to extra fuel use. The lifetime associated with different emissions and contrails varies from a few hours to several hundred years. The impact of certain gases depends on the amount and location of the emission, and the decision-making horizon, in years, when the impact is estimated. The Absolute Global Temperature Potential (AGTP) is used as a metric to measure the combined effects of emissions and contrails. This paper extends earlier work by the authors to include the effect of oxides of nitrogen in the development of aircraft trajectories to reduce the combined effects of carbon dioxide, oxides of nitrogen (NOX) and contrails. The methodology is applied to air traffic in the continental US. The paper shows the trade-offs between reducing emissions and the cost of extra fuel using a fuel sensitivity index, defined as the reduction in AGTP per kg of fuel. The paper shows the performance of the optimization strategy for decision intervals of 10, 25 and 100 years. Based on the simplified models, the inclusion of NOX emissions has a slight influence on the minimal climate impact trajectories when the decision horizons are around 25 years.

Sridhar, Banavar↗

DOE OSTI2022

Design for Carbon Conversion Product Pathways with Nuclear Power Plant Integration (PCC)

Coal is a globally abundant resource that historically has been used for power generation via combustion. As the power industry replaces coal with cleaner methods of generation, energy rich coal could be used in other chemical and fuel applications. This study presents a coal utilization option in which coal combustion is replaced with a carbon-free nuclear power plant and the coal is upgraded to valuable products for a variety of markets. Coal is prepared for conversion first by the pyrolysis process, which will optimize solid, liquid, and gaseous products based on the market size and potential product value, maximizing the monetary value of coal. This process is designed using bituminous coal from the Appalachian region as a basis to provide a pathway to preserve or transition coal-related jobs and create new jobs associated with the clean energy transition. Process modeling will be used to determine each component’s sensitivities, costs, inputs, and outputs Advanced and light-water reactors are considerations to supply the heat, steam, and electricity to the process. This paper focuses on the technical and market analysis used to determine the optimal processes and product pathways for the carbon refinery. Product pathways are on activated carbon, formic acid synthesis, and methanol synthesis for further upgrading to marketable chemical and polymer products.

01 COAL, LIGNITE, AND PEAT↗

NASA NTRS2014

Aircraft Trajectory Design Based on Reducing the Combined Effects of Carbon-Dioxide, Oxides of Nitrogen and Contrails

air trafic optimization↗

NASA NTRSDate not supplied

Carbide Coated Carbon-Carbon Heat Exchange Tubes for Nuclear Thermal Propulsion Fuel Assembly

Nuclear Thermal Propulsion (NTP) systems are proposed for human Mars missions because of the potential for reduced round-trip transit time that decreases crew exposure to space environmental hazards. NTP enables abort scenarios not available with other systems and can also be used for expanded cis-lunar mobility and deep space exploration. Heat exchange tubes, within the nuclear fuel assembly, provide flow channels for gaseous hydrogen propellant to carry the heat released during the nuclear fission reaction out of the assembly. This paper summarizes the ongoing work at NASA Centers and contractors, led by NASA Langley Research Center to develop hermetic carbide coated carbon-carbon heat exchange tubes for the NTP fuel assembly; capable of operating at 2900 K in a high-pressure, flowing hydrogen environment.

carbon-carbon↗

DOE OSTI2024

Center for Lignocellulose Structure and Formation (CLSF)

Lignocellulose is the carbon- and energy-rich material synthesized by plants when they make secondary cell walls, e.g. in woody tissues. Plants annually convert gigatons of atmospheric CO 2 into these complex and useful biomaterials that comprise over half of all biological carbon on Earth. This biological conversion helps to reduce atmospheric CO 2 that contributes to climate change while generating renewable plant cell walls that are used commercially on a massive scale in the paper, timber and textile industries. Recent technical developments open new possibilities for use of modified wood and cellulose fibers as large-scale alternatives to steel, plastics, and other nonrenewable materials with high carbon footprints and energy inputs, as well as for generation of biofuels and bio-hydrogen. Despite the utility of plant-based biomaterials, many physical and biological aspects of cell wall structure and formation remain obscure, and this limits the current scope for engineering these renewable resources for greater utility.

09 BIOMASS FUELS↗

DOE OSTI2024

Formation of functionally graded steel by laser powder bed fusion via in-situ carbon doping

Additive Manufacturing (AM) enables functional integration by combining multiple components into a single part to shorten assembly time, reduce weight, and improve performance. Laser Powder Bed Fusion (LPBF) is an important AM method due to excellent spatial resolution, surface finish, and material properties without the need for extensive post-processing. Functional integration could be enhanced by spatial tuning of properties, but LPBF cannot readily vary material composition. Here, this paper addresses a method to add spatial composition control by printing small quantities of dopants via liquid carrier prior to laser fusion. The impact of carbon black suspension added to select regions of a Stainless Steel 316 L powder bed on melt pool dimension, hardness, and porosity is reported. The distribution of the carbon between the doped and plain layers and the resulting spatial variation in hardness is measured. Optical microscopy and composition analysis show that the carbon dispersed uniformly within the layer of deposition and diffused as little as 50 μm in the build direction. Keyhole conditions dramatically increase the inter-layer transport of the dopant. The added carbon increased hardness by >50 %. Porosity increased in doped regions but remained below 1.5 % for the best processing parameters. These results demonstrate that the composition of LPBF parts could be controlled in 3-dimensions using a dopant that is soluble in the melt pool. Additional work will be required to evaluate different dopant materials and optimize processing conditions for full density, but microalloying with soluble dopants appears to be a plausible solution to enhance functional integration with LPBF.

36 MATERIALS SCIENCE↗

NASA NTRS2020

NASA’s Carbon Monitoring System (CMS) and Arctic-Boreal Vulnerability Experiment (ABoVE) Social Network and Community of Practice

The NASA Carbon Monitoring System (CMS) and Arctic-Boreal Vulnerability Experiment (ABoVE) have been planned and funded by the NASA Earth Science Division. Both programs have a focus on engaging stakeholders and developing science useful for decision making. The resulting programs have funded significant scientific output and advancements in understanding how satellite remote sensing observations can be used to not just study how the Earth is changing, but also create data products that are of high utility to stakeholders and decisions makers. In this paper we focus on documenting thematic diversity of research themes and methods used, and how the CMS and ABoVE themes are related. We do this through developing a Correlated Topic Model on the 521 papers produced by the two programs and plotting the results in a network diagram. Through analysis of the themes in these papers, we document the relationships between researchers and institutions participating in CMS and ABoVE programs and the benefits from sustained engagement with stakeholders due to recurring funding. We note an absence of policy engagement in the papers and conclude that funded researchers need to be more ambitious and explicit in drawing the connection between their research and carbon policy implications in order to meet the stated goals of the CMS and ABoVE programs.

Molly E Brown↗

DOE OSTI2022

M2CT-22IN1202096 Design for Carbon Conversion Product Pathways with Nuclear Power Plant Integration

Coal is a globally abundant resource that historically has been used for power generation via combustion. As the power industry replaces coal with cleaner methods of generation, energy-rich coal could be used in other chemical and fuel applications. This study presents a coal utilization option in which coal combustion is replaced with a carbon-free nuclear power plant and the coal is upgraded to valuable products for a variety of markets. Coal is prepared for conversion first by the pyrolysis process, which will optimize solid, liquid, and gaseous products based on the market size and potential product value, maximizing the monetary value of coal. This process is designed using bituminous coal from the Appalachian region as a basis to provide a pathway to preserve or transition coal-related jobs and create new jobs associated with the clean energy transition. Process modeling in the AspenOne Suite will be used to determine each component’s sensitivities, costs, inputs, and outputs. Dispatch modeling in the FORCE toolset will optimize the entire system and calculate the NPV for the refinery lifetime. Advanced and light-water reactors are considerations to supply the heat, steam, and electricity to the process. This paper focuses on the technical and market analysis used to determine the optimal processes and product pathways for the carbon refinery. Product pathways are on activated carbon, formic acid synthesis, and methanol synthesis for further upgrading to marketable chemical and polymer products.

01 COAL, LIGNITE, AND PEAT↗