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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 595 records · Page 33
All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

Environmental Aspects of Two Volatile Organic Compound Groundwater Treatment Designs at the Rocky Flats Site - 13135

DOE's Rocky Flats Site in Colorado is a former nuclear weapons production facility that began operations in the early 1950's. Because of releases of hazardous substances to the environment, the federally owned property and adjacent offsite areas were placed on the CERCLA National Priorities List in 1989. The final remedy was selected in 2006. Engineered components of the remedy include four groundwater treatment systems that were installed before closure as CERCLA-accelerated actions. Two of the systems, the Mound Site Plume Treatment System and the East Trenches Plume Treatment System, remove low levels of volatile organic compounds using zero-valent iron media, thereby reducing the loading of volatile organic compounds in surface water resulting from the groundwater pathway. However, the zero-valent iron treatment does not reliably reduce all volatile organic compounds to consistently meet water quality goals. While adding additional zero-valent iron media capacity could improve volatile organic compound removal capability, installation of a solar powered air-stripper has proven an effective treatment optimization in further reducing volatile organic compound concentrations. A comparison of the air stripper to the alternative of adding additional zero-valent iron capacity to improve Mound Site Plume Treatment System and East Trenches Plume Treatment System treatment based on several key sustainable remediation aspects indicates the air stripper is also more 'environmentally friendly'. These key aspects include air pollutant emissions, water quality, waste management, transportation, and costs. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2021

Chemical Heterointerface Engineering on Hybrid Electrode Materials for Electrochemical Energy Storage

Abstract The chemical heterointerfaces in hybrid electrode materials play an important role in overcoming the intrinsic drawbacks of individual materials and thus expedite the in‐depth development of electrochemical energy storage. Benefiting from the three enhancement effects of accelerating charge transport, increasing the number of storage sites, and reinforcing structural stability, the chemical heterointerfaces have attracted extensive interest and the electrochemical performances of hybrid electrode materials have been significantly optimized. In this review, recent advances regarding chemical heterointerface engineering in hybrid electrode materials are systematically summarized. Especially, the intrinsic behaviors of chemical heterointerfaces on hybrid electrode materials are refined based on built‐in electric field, van der Waals interaction, lattice mismatch and connection, electron cloud bias and chemical bond, and their combination. The strategies for introducing chemical heterointerfaces are classified into in situ local transformation, in situ growth, cosynthesis, and other strategy. The recent progress about the chemical heterointerfaces engineering specially focusing on metal‐ion batteries, supercapacitors, and Li–S batteries are introduced in detail. Furthermore, the classification and characterization of chemical heterointerfaces are briefly described. Finally, the emerging challenges and perspectives about future directions of chemical heterointerface engineering are proposed.

Li, Wenbin↗
DOE OSTI2015

Low Thermal Conductivity, High Durability Thermal Barrier Coatings for IGCC Environments

Advanced thermal barrier coatings (TBC) are crucial to improved energy efficiency in next generation gas turbine engines. The use of traditional topcoat materials, e.g. yttria-stabilized zirconia (YSZ), is limited at elevated temperatures due to (1) the accelerated undesirable phase transformations and (2) corrosive attacks by calcium-magnesium-aluminum-silicate (CMAS) deposits and moisture. The first goal of this project is to use the Solution Precursor Plasma Spray (SPPS) process to further reduce the thermal conductivity of YSZ TBCs by introducing a unique microstructural feature of layered porosity, called inter-pass boundaries (IPBs). Extensive process optimization accompanied with hundreds of spray trials as well as associated SEM cross-section and laser-flash measurements, yielded a thermal conductivity as low as 0.62 Wm⁻¹K⁻¹ in SPPS YSZ TBCs, approximately 50% reduction of APS TBCs; while other engine critical properties, such as cyclic durability, erosion resistance and sintering resistance, were characterized to be equivalent or better than APS baselines. In addition, modifications were introduced to SPPS TBCs so as to enhance their resistance to CMAS under harsh IGCC environments. Several mitigation approaches were explored, including doping the coatings with Al₂O₃ and TiO₂, applying a CMAS infiltration-inhibiting surface layer, and filling topcoat cracks with blocking substances. The efficacy of all these modifications was assessed with a set of novel CMAS-TBC interaction tests, and the moisture resistance was tested in a custom-built high-temperature moisture rig. In the end, the optimal low thermal conductivity TBC system was selected based on all evaluation tests and its processing conditions were documented. The optimal coating consisted on a thick inner layer of YSZ coating made by the SPPS process having a thermal conductivity 50% lower than standard YSZ coatings topped with a high temperature tolerant CMAS resistant gadolinium zirconate Coating made by the SPPS process. Noteworthy was the fact that the YSZ to GZO interface made by the SPPS process was not the failure location as had been observed in APS coatings.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2020

Biosystems Design to Accelerate C 3 -to-CAM Progression

Global demand for food and bioenergy production has increased rapidly, while the area of arable land has been declining for decades due to damage caused by erosion, pollution, sea level rise, urban development, soil salinization, and water scarcity driven by global climate change. In order to overcome this conflict, there is an urgent need to adapt conventional agriculture to water-limited and hotter conditions with plant crop systems that display higher water-use efficiency (WUE). Crassulacean acid metabolism (CAM) species have substantially higher WUE than species performing C 3 or C 4 photosynthesis. CAM plants are derived from C 3 photosynthesis ancestors. However, it is extremely unlikely that the C 3 or C 4 crop plants would evolve rapidly into CAM photosynthesis without human intervention. Currently, there is growing interest in improving WUE through transferring CAM into C 3 crops. However, engineering a major metabolic plant pathway, like CAM, is challenging and requires a comprehensive deep understanding of the enzymatic reactions and regulatory networks in both C 3 and CAM photosynthesis, as well as overcoming physiometabolic limitations such as diurnal stomatal regulation. Recent advances in CAM evolutionary genomics research, genome editing, and synthetic biology have increased the likelihood of successful acceleration of C 3 -to-CAM progression. Here, we first summarize the systems biology-level understanding of the molecular processes in the CAM pathway. Then, we review the principles of CAM engineering in an evolutionary context. Lastly, we discuss the technical approaches to accelerate the C 3 -to-CAM transition in plants using synthetic biology toolboxes.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2021

Accelerated basis adaptation in homogeneous chaos spaces

Polynomial chaos expansions (PCE) provide an efficient approach to uncertainty quantification (UQ) and have been adapted to diverse applications across the spectrum of science and engineering. For situations involving large stochastic parameterizations, the curse of dimensionality renders PCE-based methods computationally prohibitive. A basis adaptation approach for PCE was proposed by Tipireddy and Ghanem (2014) which transforms the input random variables through an isometry such that sufficient probabilistic characterization of specific quantities of interest (QoI) is concentrated in an algebraic manifold embedded in the linear span of the dominant transformed variables. While quite versatile, that original version of the PCE basis adaptation exhibited slow convergence for a number of problems of practical significance. In the present paper, we propose two novel methods to accelerate the convergence of the original basis adaptation approach, thus expanding its reach while also providing insight into its performance. In the first method, information gained from a pilot PCE representation is used to correct the mean and Gaussian coefficients in the adapted space. By taking advantages of probabilistic information in higher dimensional adaptation gleaned from an initial adaptation, the second method updates the rotation matrix used to identify the dominant transformed variables. In this manner, the new rotation matrix concentrates even more probabilistic information in its first few dimensions. These two method can be combined to achieve even better performance, the combined method is referred to as sequentially optimized adaptation method. Here, the methods are demonstrated on an analytical test function and a model of a space structure with several sub-components and a non-smooth quantity of interest representing the maximum acceleration over time. Both methods achieve accelerated convergence of the basis adaptation approach with negligible additional costs.

Accelerated convergence↗
DOE OSTI2016

Modeling of interdendritic porosity defects in an integrated computational materials engineering approach for metal casting

Modeling and simulation of multiphysical phenomena needs to be considered in the design and optimization of mechanical properties of cast components in order to accelerate the introduction of new cast alloys. The data on casting defects, including microstructure features, is crucial for evaluating the final performance-related properties of the component. Here in this paper, the required models for the prediction of interdendritic casting defects, such as microporosity and hot tears, are reviewed. The data on calculated solidification shrinkage is presented and its effects on microporosity levels discussed. Numerical simulation results for microporosity are presented for A356, 356 and 319 aluminum alloys using ProCAST TM software. The calculated pressure drop of the interdendritic liquid was observed to be quite significant and the regions of high-pressure drop can be used as an indicator of the severity of interdendritic microporosity defects.

36 MATERIALS SCIENCE↗
DOE OSTI2018

HIGH-STRENGTH LIGHTWEIGHT ENGINES FOR HEAVY-DUTY DIESEL TRUCKS

This project with Cummins supports the development of next generation heavy duty diesel engines that can achieve a 50% or better Break Thermal Efficiency (BTE). The fuel efficiency roadmap for the 50% BTE engine considers six main areas for efficiency improvement in the baseline engine, several of which involve making more efficient use of thermal energy (heat) in the engine. Increased operating temperatures and improved thermal management are expected to enable significant increases in $power$ $density$, thus resulting in greater power output for the same sized engine or engine downsizing (or light weighting) for the same power output. However, it has become apparent that several key components will be exposed to temperatures beyond the capabilities of current engine and exhaust materials, requiring the availability of the next generation of high temperature materials to allow the engine to reach the targeted efficiencies, commercially viable durability, and emission targets. The objective of this project was to identify and/or develop key materials, and evaluate their critical properties to enable the design and development of a lightweight, higher efficiency engine, with enhanced temperature capability and reduced heat-loss to the atmosphere in order to facilitate waste heat recovery and improved efficiency. An increase in the temperature capability of exhaust manifold materials, and piston materials were identified as having a positive influence on the efficiency of the next generation diesel engines. Since the current materials (High SiMo cast irons used in exhaust manifolds, and 4140 steel in pistons) are already operating near their limits of their temperature and strength capabilities, it was determined that new materials with the right combination of properties are required for these components. Oxidation and constrained thermal fatigue tests were used to down-select CF8C plus (CF8CP), a cast austenitic stainless steel, for exhaust manifolds capable of operating at higher temperatures. A prototype exhaust manifold was fabricated using CF8CP and successfully tested in a marine engine. A functionally graded multiple-layer thermal barrier coating system was designed with four layers of mixed bondcoat alloy (NiCoCrAlYHfSi) and yttria stabilized zirconia (YSZ) and was shown to reduce the effective thermal conductivity of the coating-substrate (steel and Ti-6Al-4V) system. The graded alloy and YSZ mixture were intended to achieve better match of thermal expansion coefficient (CTE) and minimize thermal stresses. Such coatings can increase the temperature capability of pistons fabricated from steel and Ti-alloys. Effect of oil additives and friction conformal contact friction tests showed there was a 15-30% reduction in friction by the polymer-graphite composite coating compared to the uncoated steel piston. Standalone Mn-P coating had little beneficial impact. Changing the oil from CJ-4 to PC-11 had little impact on the friction behavior in boundary lubrication. Wear behavior was tested under a point contact configuration with a high contact pressure. The candidate CK-4 oil showed similar or slightly better lubricity compared to the CJ-4 oil while the candidate FA-4 oil decisively increased the piston skirt wear. Although both coatings prevented scuffing failure observed for the uncoated steel skirt in a base oil without an additive package, they surprisingly caused a higher piston wear rate when tested in any of the fully formulated engine oil. The detrimental impact was attributed to the Mn-P film, either as a standalone coating, or a coating interlayer. The porous and brittle Mn-P film was broken during the wear test and the released hard Mn-P grains are suspected to cause third-body abrasion to accelerate the wear process. This work also evaluated the feasibility of developing an improved high temperature, low mass, cost-neutral turbocharger compressor wheel for heavy-duty engine applications from TiAl using additive manufacturing, utilizing its unique ability to fabricate high strength, low weight structures. This work has shown that the phase transforming nature of the TiAl alloys enable obtaining equiaxed microstructures in the as-built state without the need for tedious beam parameter manipulations. The HIPed structures have good RT tensile properties that will enable them to be surface machined to the required tolerance that can 2 then be heat treated to obtain the desired microstructures. Additionally, the negligible residual stresses stemming from the high build chamber temperatures ensure the parts are formed without cracks (one of the major issues in traditional manufacturing of these intermetallics).

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2018

Marrying Quality Assurance with Design Engineering - A Winning Partnership! But, a Cultural Divide?: Preprint

Investors would like to be confident that a PV plant will work as promised before investing large sums of money. Data showing that PV modules can withstand thousands of hours of accelerated testing are a comfort, but are not sufficient. An inability to be confident of every aspect of the system can motivate higher interest rates; high degradation or failure rates can substantially decrease the return on investment and the value of the plant for resale later on. In the end, a winning partnership is obtained when a carefully engineered, durable design is married with a robust quality management system and the marriage is extended across all parts of the value chain. However, this marriage is challenging because of the conventional cultural divide between design engineers and quality management specialists. This paper discusses the motivation for increased emphasis on quality assurance and describes three new standards that detail requirements for a higher level of quality assurance for 1) PV module manufacturing, 2) inverter and other balance-of-systems (BOS) manufacturing, and 3) control of the system installation and operation. The paper concludes with a discussion of the challenges and benefits of marrying the quality assurance program with further optimization of the PV system design.

14 SOLAR ENERGY↗
DOE OSTI2026

Selective CO 2 Reduction by Bis(bipyridine)cobalt(II) Catalysts: The Role of Pendant Pyridine as a Proton Acceptor

Electrochemical CO 2 reduction reaction (CO 2 RR) catalyzed by molecular earth-abundant metal catalysts is a promising strategy to convert CO 2 into value-added products. One recent trend in this field has been focusing on the rational design of catalysts by incorporating redox-active ligands and modifying the secondary coordination sphere (SCS) to achieve efficient and selective CO 2 RR. Herein, we report a series of Co bis­(bipyridine) catalysts featuring various dangling groups, such as pyridine, tertiary amine, or butyl, in the secondary coordination sphere (Co-PyMe, Co-Py, Co-PrN, and Co-Bu). Efficient, selective electrocatalytic CO 2 RR was achieved by the complexes after the generation of triply reduced intermediate consisting of a Co I center and a dianionic ligand, producing CO as the major product and trace amount of H 2 . Strong correlations with the identity of dangling groups and turnover frequency (TOF) have been observed, in which Co-PyMe displayed the highest TOF (1086 s –1 in MeCN/H 2 O). Mechanistic studies indicated that the acceleration of CO 2 RR with pyridine-functionalized catalysts were derived from the protonation of pyridine dangling groups which participated as weak acids in the H-bonding network with exogenous proton sources, stabilizing CO 2 -bound intermediates and facilitating proton transfer. In addition, precatalytic CO 2 binding and activation at the third reduction (−2.1 V) was revealed by CV and SEC-IR studies. The resultant doubly reduced CO-bound species acted as a trapping state which inhibited CO 2 RR electrocatalysis. Regeneration of active species was accessed via reductive dissociation of CO at a more negative potential. In conclusion, this study highlights the combined effects of redox-active ligands and pyridine/pyridinium as SCS groups on CO 2 RR catalysis and provides design principles for future development of CO 2 RR catalysts utilizing pyridine/pyridiniums as SCS functional groups to fine-tune the catalytic activity.

CO2 reduction↗
DOE OSTI2026

Facile synthesis of Co(OH)2 nanoneedle arrays grown on stainless steel for industrial electrochemical oxygen evolution reaction

The electrochemical oxygen evolution reaction (OER) is a critical half-reaction in a variety of energy conversion and storage applications, however, OER suffers from sluggish kinetics due to the four proton-electron transfer processes. To remedy this, interfacial engineering proves an effective strategy to design high active OER catalysts. Herein, we report a facile synthesis of Co(OH)2 nanoneedle (Co-NN) arrays grown on stainless steel (SS) via a one-step hydrothermal reaction, and the resultant impressive OER performance. Particularly, the Co-NN/SS needs 267, 307, and 576 mV overpotentials to reach 10, 100, and 1000 mA cm−2 in 1 M KOH & room temperature, and the overpotentials drop to 199, 257, and 283 mV to achieve the same current densities in 30 wt% KOH & 80 °C. Additionally, an alkaline water electrolysis (AWE) cell coupled with Co-NN/SS anode and PtRu/NiMo cathode only requires 1.65 and 1.73 V iR-free cell voltage to reach 1.0 and 2.0 A cm−2, respectively. The sterling OER performance could be attributed to four possible reasons, the Fe in SS surface tailoring the electronic properties of Co(OH)2, the mixed metal oxides on SS surface accelerating surface reconstruction of Co(OH)2 nanoneedles into CoOOH active species, a Ni-rich surface layer formation cooperatively boosting the OER activity, and a local electric field effect concentrating reactants on the tip surface and accelerating the mass transfer. This work provides a facile approach for synthesizing highly efficient OER catalysts for industrial applications by interfacial engineering.

Lyu, Xiang [ORNL] (ORCID:0000000208673248)↗
DOE OSTI2015

Building blocks for correlated superconductors and magnets

Recent efforts at Los Alamos to discover strongly correlated superconductors and hard ferromagnets are reviewed. While serendipity remains a principal engine of materials discovery, design principles and structural building blocks are beginning to emerge that hold potential for predictive discovery. Successes over the last decade with the so-called “115” strongly correlated superconductors are summarized, and more recent efforts to translate these insights and principles to novel hard magnets are discussed. While true “materials by design” remains a distant aspiration, progress is being made in coupling empirical design principles to electronic structure simulation to accelerate and guide materials design and synthesis.

36 MATERIALS SCIENCE↗
DOE OSTI2025

A SynBio explosion: a whole new world for Rubisco engineering

The first Escherichia coli synthetic biology (SynBio) system to successfully heterologously assemble chloroplast Rubisco represented the culmination of decades of Rubisco biogenesis research (Aigner et al., 2017). This system for Arabidopsis Rubisco ushered in a new era of higher throughput Rubisco studies, and has since been adapted for a limited number of other Rubiscos, accelerating both fundamental and applied Rubisco research. Archer et al. (2025) have developed new SynBio systems to assemble a larger variety of C 3 Rubiscos and the first C 4 and monocot Rubiscos, greatly expanding crop Rubisco engineering capabilities. Their explorations of chaperone selectivity and versatility could enable rapid production of SynBio systems for additional species.

Rubisco↗
DOE OSTI2024

Performance-based earthquake early warning for tall buildings

The ShakeAlert Earthquake Early Warning (EEW) system aims to issue an advance warning to residents on the West Coast of the United States seconds before the ground shaking arrives, if the expected ground shaking exceeds a certain threshold. However, residents in tall buildings may experience much greater motion due to the dynamic response of the buildings. Therefore, there is an ongoing effort to extend ShakeAlert to include the contribution of building response to provide a more accurate estimation of the expected shaking intensity for tall buildings. Currently, the supposedly ideal solution of analyzing detailed finite element models of buildings under predicted ground-motion time histories is not theoretically or practically feasible. The authors have recently investigated existing simple methods to estimate peak floor acceleration (PFA) and determined these simple formulas are not practically suitable. Instead, this article explores another approach by extending the Pacific Earthquake Engineering Research Center (PEER) performance-based earthquake engineering (PBEE) to EEW, considering that every component involved in building response prediction is uncertain in the EEW scenario. Additionally, while this idea is not new and has been proposed by other researchers, it has two shortcomings: (1) the simple beam model used for response prediction is prone to modeling uncertainty, which has not been quantified, and (2) the ground motions used for probabilistic demand models are not suitable for EEW applications. In this article, we address these two issues by incorporating modeling errors into the parameters of the beam model and using a new set of ground motions, respectively. We demonstrate how this approach could practically work using data from a 52-story building in downtown Los Angeles. Using the criteria and thresholds employed by previous researchers, we show that if peak ground acceleration (PGA) is accurately estimated, this approach can predict the expected level of human comfort in tall buildings.

58 GEOSCIENCES↗
DOE OSTI2026

Architector 2.0: Expanded Capabilities for Metal Complex Engineering

Automated three-dimensional molecular construction from two-dimensional graph representations is critical to high-throughput discovery eIorts. Software capabilities in this area have accelerated research across fields ranging from protein design and drug discovery to transition metal catalyst development. When Architector was first introduced, it uniquely enabled high-throughput, chemically relevant three-dimensional construction of f-element complexes. Since its introduction, Architector has been applied in large-scale computational campaigns, targeted studies in critical mineral extraction, and artificial intelligence-driven discovery eIorts.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Solar Utility Network Deployment Acceleration

The National Rural Electric Cooperative Association (NRECA) is the national association representing 833 distribution and 62 generation and transmission (G&T) cooperatives. From booming suburbs to remote rural farming communities, America’s electric cooperatives are energy providers and engines of economic development and way of life for more than 19 million American homes, businesses, farms, and schools in 47 states across the U.S. Member owned and responsive, generally smaller than investor-owned and municipal utilities, often more nimble in services for members, co-ops provide the U.S. Department of Energy (DOE) with a strong partner for testing and accelerating utility-scale solar design, pricing, and delivery models.

14 SOLAR ENERGY↗
DOE OSTI2020

Status and challenges for the application of platinum group metal-free catalysts in proton-exchange membrane fuel cells

Platinum group metal-free (PGM-free) electrocatalysts are an important class of materials for the sustainable energy economy and significant effort has been made towards developing PGM-free catalysts to replace their costly Pt counterparts in fuel cell electric vehicles. The progress made in activity over the last decade is reviewed, along with synthesis strategies for more controlled active site formation and performance gains achieved through electrode engineering. The increased focus on durability, the growing understanding of degradation mechanisms, and the need for standard performance and accelerated stress test protocols are discussed.

25 ENERGY STORAGE↗
DOE OSTI2024

Defect diffusion graph neural networks (d2gnn)

SAND2025-01004O Defect Diffusion Graph Neural Networks (d2gnn) is a software tool that assists in the discovery of new materials for high-temperature, clean-energy applications. It uses advanced graph neural networks to model the relationship between material structures and their defect properties. The application helps predict how materials will behave under different conditions and accelerates the development of innovative materials. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.

Witman, Matthew [Sandia National Lab. (SNL-CA), Li↗
DOE OSTI2021

Developing a Hybrid Electric Vehicle Eco-Cooperative Adaptive Cruise Control System at Signalized Intersections.

This study develops an eco-driving strategy for hybrid electric vehicles (HEVs) in the vicinity of signalized intersections, entitled HEV Eco-Cooperative Adaptive Cruise Control at Intersections (Eco-CACC-I). The proposed system computes real-time, energy-optimized vehicle trajectories using HEV vehicle dynamics and energy consumption models. In the proposed system, a simple HEV energy model is used to compute the instantaneous fuel consumption. This HEV energy model is selected since it is general, transferable, and can be easily used to compute instantaneous energy consumption levels for HEVs without the additional input of vehicle engine data or complicated power control strategies. In addition, a vehicle dynamics model is used to capture the relationship between speed, acceleration level, and tractive/resistance forces on vehicles. The energy-optimum problem is formulated as an optimization problem with constraints, which is solved using a moving-horizon dynamic programming approach. The proposed HEV Eco-CACC-I system was tested to evaluate its performance for various speed limits, roadway grades, and signal timings. Lastly, the proposed HEV controller was implemented in a microscopic traffic simulation software to test its network-wide performance. The test results from an arterial corridor with three signalized intersections demonstrate that the proposed system can effectively reduce stop-and-go traffic in the vicinity of signalized intersections producing savings of 7.4% in energy consumption, 5.8% in traffic delay and 23% vehicle stops, respectively.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗