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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 271 records · Page 15

Empirical correlations between the function of entropy ( Z S ) and net artificial viscous work in a shock physics hydrocode

Entropy is a state variable that may be obtained from any thermodynamically complete equation of state (EOS). However, hydrocode calculations that output the entropy often contain numerical errors; this is not because of the EOS, but rather the solution techniques that are used in hydrocodes (especially Eulerian) such as convection, remapping, and artificial viscosity. Here, in this work, empirical correlations are investigated to reduce the errors in entropy without altering the solution techniques for the conservation of mass, momentum, and energy. Specifically, these correlations are developed for the function of entropy Z S , and they depend upon the net artificial viscous work, as determined via Sandia National Laboratories’ shock physics hydrocode CTH. These results are a continuation of a prior effort to implement the entropy-based CREST reactive burn model in CTH, and they are presented here to stimulate further interest from the shock physics community. Future work is planned to study higher-dimensional shock waves, shock wave interactions, and possible ties between the empirical correlations and a physical law.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Continuum shock mixture models for Ni+Al multilayers: Individual layers and bulk equations of state

Continuum shock mixture models are reviewed and applied to determine the equations of state for five different compositions of Ni x Al y ⁠, as well as bulk Ni+Al reactive multilayers, by combining the fundamental property data for elemental nickel and aluminum. From the literature, we down-select and evaluate two analytical models for the mixture Hugoniot, i.e., the well-known method of kinetic energy averaging (KEA) and a recent model proposed by Jordan and Baer [J. Appl. Phys. 111, 083516 (2012)]. Fundamentally, the former method assumes pressure equilibrium, whereas the latter assumes a common particle velocity and mixture sound speed from compressible two-phase cavitating flows. Additionally, we construct thermodynamically complete equations of state by fitting Einstein oscillator series models for the specific heat at constant volume. Finally, the solid solution approximation is invoked for intermetallic compositions, which are not strictly physical mixtures. Overall, the KEA model provides a better fit to the available Ni x Al y and Ni+Al multilayer shock compression data; however, there are combinations of material properties where the performance of these two models is thought to be reversed. Moreover, the results of this work include the first analytical solution of Jordan–Baer that does not require numerical root finding, as well as proposed modifications to the Einstein oscillator series to incorporate some effects of local pressure–temperature equilibrium and reaction–diffusion. Future work is planned that will use these equations of state in mesoscale simulations to study shock-induced reaction in Ni+Al multilayers, and the intended application is illustrated with a brief 2D hydrocode example.

36 MATERIALS SCIENCE↗

The role of emerging scientists in restoration ecology: insights from a SER2023 conference workshop

Emerging professionals are crucial in advancing ecological restoration by connecting newcomers with established leaders and blending new ideas with traditional practices. This paper highlights the vital role emerging scientists play in restoration ecology and the Society for Ecological Restoration (SER). A survey conducted during the SER2023 conference workshop, organized by the Students and Emerging Professionals committee, showed that emerging professionals contribute significantly to every stage of scientific work, from planning to publication. However, participants emphasized the scarcity of funding opportunities for non‐senior scientists, which limits academic growth. The workshop underscored the importance of nurturing emerging professionals to develop future leaders for SER and ensure continuity. Fostering non‐hierarchical and inclusive networking is key to engaging and empowering these professionals, ultimately contributing to the long‐term success of ecological restoration efforts.

Weidlich, Emanuela W. A.↗

EV Watts Public Database

With the rapid increase in vehicle electrification, there is a need for up-to-date, publicly available national data to understand end user charging and driving patterns, as well as vehicle and infrastructure performance, to inform research planning. Energetics worked with various partners to collect and analyze plug-in electric vehicle (PEV) and electric vehicle supply equipment (EVSE) data from 2019 to 2022. All sensitive attributes have been removed from this publicly available dataset. Researchers from one of the partner national labs under non-disclosure agreement (NDA) can request access to additional attributes by reaching out to evwattsdata@energetics.com.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

AMPP-4 Metric Dashboard

The AMPP-4 Metric Dashboard is an interactive tool used for visualizing key performance indicators and milestones for the various teams in the Material Recovery & Recycle (AMPP-4) group. This dashboard provides current group data for FY25 tracking purposes. The dashboard is organized by various chapters: 1) AMPP-4 overview, 2) Scheduling, and 3) individual chapters for each team. AMPP-4 supports 7 teams, where the day- and swing-shift aqueous demolition teams are treated as one team for the purpose of metric tracking. The dashboard is used internally to monitor the success and health of the AMPP-4 teams. Additionally, the dashboard can be used externally to support programmatic reporting to sponsors and aid in future milestone and work package planning.

97 MATHEMATICS AND COMPUTING↗

Investigation of Ammonia Carrier Materials for Next Generation Ammonia Dosing System - CRADA 334 (Abstract)

Lean-burn gasoline and diesel engines can offer substantially higher fuel efficiency, good driving performance, and reduced carbon dioxide emission compared to stoichiometric gasoline engines. Various catalyst technologies have been developed to remove the pollutants from these engines. For example, a three-way catalyst (TWC) is used to remove hydrocarbons (HC), carbon monoxide (CO), and nitrogen oxides (NOx) from gasoline engines during the stoichiometric conditions. During the lean-burn conditions, a TWC or a diesel oxidation catalyst (DOC) is used to control HC and CO emissions. NOx is removed by either lean NOx trap catalyst (LNT) that can store NOx under lean conditions and reduce NOx under rich conditions, or selective catalytic reduction catalyst (SCR) that can selectively remove NOx with a reducing agent. Among the NOx reduction catalyst technologies, SCR offers a number of advantages, including excellent NOx reduction efficiency over a wide range of temperatures and overall lower system cost. In fact, the SCR technology using ammonia (NH3) as reductant has been proven effective and used commercially for the removal of NOx emissions from stationary sources since the 1970s. Currently, SCR is being used to meet the NOx emission standards for diesel engines in Europe and North America, and also being considered for meeting the future NOx emission standards for lean-burn gasoline engines. Because of the challenges associated with storage, handling and transportation of ammonia on a vehicle, aqueous urea solution (e.g., Diesel Exhaust Fluid, AdBlue) has been developed as ammonia storage compound for mobile applications. When the aqueous urea solution is sprayed into exhaust gas stream, urea is decomposed to release ammonia, which then reduces NOx over the downstream SCR catalyst. Although aqueous urea solution technology has enabled automakers and engine manufacturers to meet the current NOx emission standards, this process of releasing ammonia requires a hot exhaust gas and sufficient mixing, creating challenges for low temperature NOx emission control and aftertreatment system packaging. For these reasons, alternative technologies have been developed as ammonia sources (e.g., solid urea, ammonium carbamate, metal ammine chloride) during the past few years. These technologies promise more convenient handling and distribution of ammonia sources, and help maximize the low-temperature performance of SCR catalysts and reduce the overall system volume and weight. However, none of these alternative technologies can be successfully implemented without the industry consensus. Therefore, the USCAR SCR work group, which is comprised of representatives from GM, Ford, and Chrysler, has decided to investigate the potential alternative ammonia carriers, define common standard vehicle interfaces, and address personal and environmental safety concerns with part suppliers and chemical companies. Under this CRADA Project, USCAR and Battelle will investigate alternative ammonia carrier materials that are currently under development. Based on the data and information derived under the CRADA project, the USCAR SCR work group plans to build the consensus and make recommendations for the industry.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Investigation of Ammonia Carrier Materials for Next Generation Ammonia Dosing System - CRADA 334 (Abstract)

Lean-burn gasoline and diesel engines can offer substantially higher fuel efficiency, good driving performance, and reduced carbon dioxide emission compared to stoichiometric gasoline engines. Various catalyst technologies have been developed to remove the pollutants from these engines. For example, a three-way catalyst (TWC) is used to remove hydrocarbons (HC), carbon monoxide (CO), and nitrogen oxides (NOx) from gasoline engines during the stoichiometric conditions. During the lean-burn conditions, a TWC or a diesel oxidation catalyst (DOC) is used to control HC and CO emissions. NOx is removed by either lean NOx trap catalyst (LNT) that can store NOx under lean conditions and reduce NOx under rich conditions, or selective catalytic reduction catalyst (SCR) that can selectively remove NOx with a reducing agent. Among the NOx reduction catalyst technologies, SCR offers a number of advantages, including excellent NOx reduction efficiency over a wide range of temperatures and overall lower system cost. In fact, the SCR technology using ammonia (NH3) as reductant has been proven effective and used commercially for the removal of NOx emissions from stationary sources since the 1970s. Currently, SCR is being used to meet the NOx emission standards for diesel engines in Europe and North America, and also being considered for meeting the future NOx emission standards for lean-burn gasoline engines. Because of the challenges associated with storage, handling and transportation of ammonia on a vehicle, aqueous urea solution (e.g., Diesel Exhaust Fluid, AdBlue) has been developed as ammonia storage compound for mobile applications. When the aqueous urea solution is sprayed into exhaust gas stream, urea is decomposed to release ammonia, which then reduces NOx over the downstream SCR catalyst. Although aqueous urea solution technology has enabled automakers and engine manufacturers to meet the current NOx emission standards, this process of releasing ammonia requires a hot exhaust gas and sufficient mixing, creating challenges for low temperature NOx emission control and aftertreatment system packaging. For these reasons, alternative technologies have been developed as ammonia sources (e.g., solid urea, ammonium carbamate, metal ammine chloride) during the past few years. These technologies promise more convenient handling and distribution of ammonia sources, and help maximize the low-temperature performance of SCR catalysts and reduce the overall system volume and weight. However, none of these alternative technologies can be successfully implemented without the industry consensus. Therefore, the USCAR SCR work group, which is comprised of representatives from GM, Ford, and Chrysler, has decided to investigate the potential alternative ammonia carriers, define common standard vehicle interfaces, and address personal and environmental safety concerns with part suppliers and chemical companies. Under this CRADA Project, USCAR and Battelle will investigate alternative ammonia carrier materials that are currently under development. Based on the data and information derived under the CRADA project, the USCAR SCR work group plans to build the consensus and make recommendations for the industry.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

New charged-particle transport computational capability: the SIT code An L-4 milestone

We have developed a new high-fidelity code for direct transport of charged particles using the simple integral transport method. The code can be coupled to the outputs of any hydrodynamical simulation code in 1-D, 2-D or 3-D. In this report we summarize the formalism involved in treating complex transport problems. We present physical examples wherein we have used the code to calculate the transport of alpha particles. Future work is planned to study the sensitivity of hydrodynamical mix to charged-particle radiochemistry and reaction-in-flight neutrons for the complex inertial confinement fusion problems encountered at NIF and at the Z-machine.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗

Technical Track on Biomass Carbon Removal and Storage (BiCRS): Mapping bioresources, phase 1 - Consistency check comparing Mission Innovation’s Data Visualization Tool for Bioresources and the Clean Energy Ministerial Biofuture Initiative Global Biomass data accessible via the US Department of Energy’s Bioenergy Knowledge Discovery Framework (KDF)

The Mission Innovation (MI) Carbon Dioxide Removal (CDR) Mission, Technical Track on Biomass Carbon Dioxide Removal and Storage (BiCRS), has produced a biomass resource database for its members. In parallel, Oak Ridge National Laboratory (ORNL) developed the International Feedstock Reporting data portal—herein referred to as the CEM Biofuture-KDF data—on behalf of the Clean Energy Ministerial Biofuture Initiative (CEM Biofuture), as a specific task under Biofuture’s 2024–25 Action Plan. This work was conducted at the request of CEM Biofuture and funded by the U.S. Department of Energy in support of that initiative, and it is hosted within DOE’s Knowledge Discovery Framework (KDF).

09 BIOMASS FUELS↗

Expedition UT-GOM2-2 Methods

Methods used during the University of Texas (UT) Deepwater Hydrate Coring Expedition (UT-GOM2-2) include work done onboard the Helix Q4000 in the offshore Gulf of America (Gulf of Mexico), herein “the Gulf”, “dockside” in Salt Lake City, Utah, and some shore-based work in individual laboratories. The goal of this report is two-fold: to provide enough detail on the methods so they can be repeated by others; and to provide a reference document for the team to enhance cross-disciplinary understanding and knowledge. Methods include drilling operations, depth references and depth modification, downhole tool deployment, coring tool performance assessment, core processing, lithostratigraphy, biostratigraphy, as well as physical properties, including core logging and imaging, rock magnetism, dissolved methane concentration, hydrate saturation, microbiology, and geochemistry. An extensive amount of operational work and planning was required before mobilization of the expedition to permit, build mobile labs, and test downhole tools for deepwater drilling.

03 NATURAL GAS↗

Disassembly and Initial Post-Irradiation Examination of the Mini99 Experiment

The Miniature Fuel Molybdenum-99 (Mini99) experiment is a first-of-a-kind experiment in the High Flux Isotope Reactor. Mini99 is the first MiniFuel irradiation experiment to use liquid metal inside the MiniFuel subcapsule for additional temperature control. In this work, the initial post-irradiation examination is reported. As-built simulations were conducted and compared with designs, and physical post-irradiation examinations were conducted to determine actual test temperatures via SiC thermometry samples, to evaluate the extent of fission gas release from the samples, and to remove the fuel from the subcapsules. As-built simulations compared well with experiment designs and were in reasonable agreement with the measured temperatures inferred from the passive SiC thermometers. Additionally, fission gas release values were relatively small (on the order of 3%); one sample reached approximately 8%. Although some of this behavior is attributable to recoil, most of the gas release was likely caused by the physics of the fuel behavior during the test. Finally, disassembly showed that at least four of the fuel samples degraded into small components and granules at some point during the test, with the state of the other two samples unproven. Additional work is planned for further examination of these samples via various microscopy techniques.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Skylab experiment performance evaluation manual

A series of preparation analyses used for evaluating the performance of the Skylab corollary experiments under preflight, in-flight, and postflight conditions is given. Experiment continegency plan work-around procedure and malfunction analyses are presented in order to assist in making the experiment operationally succesful.

Meyers, J. E.↗

Modifications of the wideband FM TDRS system

The wideband FM scheme for the Tracking and Data Relay Satellite (TDRS) system is discussed. The technique achieves a spread-spectrum advantage against multipath and interference through the inclusion of a large deviation FM subcarrier. The signal also permits co-channel spread-spectrum multipath access (SSMA) on the downlink from mission spacecraft to TDRS. Each user is assigned a unique combination of carrier and subcarrier which allows the ground receiver to separate user signals with overlapping spectra. The system was modified by the addition of a low-deviation fine range tone to both the uplink and the downlink, separate from the wide-deviation subcarrier. The magnitude of the interference components due to other SSMA signals are analyzed. A carrier and subcarrier frequency plan was worked out based on the modified signal format. A configuration to accommodate 42 and 60 users is described. The inclusion of ambiguity resolving ranging sidetones is also discussed.

Wachsman, R. H.↗

High spatial resolution multi-color observations of Neptune during occultation by the moon

Preparations for the observation of Mars occultation using the 36 inch telescope on a C-141 airborne observatory were described, including technical improvements made to existing equipment. The abstracts of the following four publications supported by the grant were presented: (1) atmosphere composition from refractivity measurements made during occultations, (2) how big is lapetus?, (3) the diameter of Titan, (4) design and operating characteristics of voltage to frequency converters suited for occultation work. The planned observation of the April 8, 1976 occultation of the epsilon Gem star from the C-141 airborne observatory was described.

Veverka, J.↗

National Transonic Facility Fan Blade prepreg material characterization tests

The test program for the basic prepreg materials used in process development work and planned fabrication of the national transonic facility fan blade is presented. The basic prepreg materials and the design laminate are characterized at 89 K, room temperature, and 366 K. Characterization tests, test equipment, and test data are discussed. Material tests results in the warp direction are given for tensile, compressive, fatigue (tension-tension), interlaminar shear and thermal expansion.

Klich, P. J.↗

Influence of rotor blade tip shape on tip vortex shedding - An unsteady, inviscid analysis

An unsteady potential flow panel method is described based on a time-stepping procedure and using planar quadrilateral panels to represent the surface of thick blades. Each panel has a constant source and doublet distribution and a central control point where an internal Dirichlet boundary condition is applied. The method includes detail paneling around the tip edge and offers the facility of prescribing a tip-edge separation. Preliminary results are shown for four blade tip shapes which are treated as semi-span wings oscillating in pitch about a mean angle of attack of 6 deg. Further work is planned for the wake model before proceeding to higher angles of attack.

Maskew, B.↗

Test results of modified electrical charged particle generator for application to fog dispersal

Modifications to a charged particle generator for use in fog dispersal applications were made and additional testing carried out. The modified nozzle, however, did not work as planned, and reported results are the unmodified nozzle. The addition of a positive displacement pump to supply the liquid water was highly successful. Measurements of the generator output current were made with a cylindrical collector system as well as with the needle probe used in previous studies. Measurements with the cylindrical collector and the needle probe showed identical agreement within the variability of the experiment. A high-voltage prove was purchased, and measurements of the corona voltage as well as the voltage variation in the charged particle jet were made. Electric fields in the vertical direction on the order of 1,000,000 v/m were measured. The voltage distribution along the centerline of the jet was compared with the numerical solutions of the Poisson equation and showed very good agreement. Velocity measurements using a pitot tube were made. The resulting measurements were compared with theoretical and other reported experimental results. The measured data showed the appropriate trends and agreed well with reported results. Based on the measured current-to-mass ratio from the charged particle generator, a calculation of the average droplet size was made. Droplet sizes were estimated to range between 0.8 and 0.4 microns. Using measured data, an analysis of the height to which the droplet can be dispersed by the charged particle generator was made. Although the mathematical model is highly simplified, the results indicated that particles would achieve heights on the order of 80 m.

Frost, W.↗