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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 1,405 records · Page 78

All sources NASA NTRS DOE OSTI

DOE OSTI2020

Fuel injector including a lobed mixer and vanes for injecting alternate fuels in a gas turbine

A fuel injector for injecting alternate fuels having a different energy density in a gas turbine is provided. A first fuel supply channel (18) may be fluidly coupled to a radial passage (22) in a plurality of vanes (20) that branches into passages (24) (e.g., axial passages) to inject a first fuel without jet in cross-flow injection. This may be effective to reduce flashback in fuels having a relatively high flame speed. A mixer (30) with lobes (32) for injection of a second fuel may be arranged at the downstream end of a fuel delivery tube (12). A fuel-routing structure (38) may be configured to route the second fuel within a respective lobe so that fuel injection of the second fuel takes place radially outwardly relative to a central region of the mixer. This may be conducive to an improved (e.g., a relatively more uniform) mixing of air and fuel.

42 ENGINEERING↗

DOE OSTI2020

Systems and methods for augmenting a satellite based navigation system with alternative position and timing data

Various technologies pertaining to integrating a positioning or timing solution from an alternative position, navigation, or timing (PNT) system into a satellite-based-navigation system are described herein. The PNT system generates a position/timing (P/T) solution that indicates a current position or current time of the PNT system. The P/T solution is provided as input to a simulation of a satellite constellation of the satellite-based-navigation system, and a constellation signal is generated based on the simulation and the P/T solution. The constellation signal is formatted according to a navigation signal format of the satellite-based-navigation system such that when the constellation signal is provided to a receiver of the satellite-based-navigation system, the receiver computes a P/T solution that indicates the current position or the current time identified by the PNT system.

24 POWER TRANSMISSION AND DISTRIBUTION↗

DOE OSTI2021

Method and apparatus for ion mobility separations utilizing alternating current waveforms

Methods and apparatuses for ion manipulations, including ion trapping, transfer, and mobility separations, using traveling waves (TW) formed by continuous alternating current (AC) are disclosed. An apparatus for ion manipulation includes a surface to which are coupled a first plurality of continuous electrodes and a second plurality of segmented electrodes. The second plurality of segmented electrodes is arranged in longitudinal sets between or adjacent to the first plurality of electrodes. An RF voltage applied to adjacent electrodes of the first plurality of electrodes is phase shifted by approximately 180° to confine ions within the apparatus. An AC voltage waveform applied to adjacent electrodes within a longitudinal set of the second plurality of segmented electrodes is phase shifted on the adjacent electrodes by 1°-359° to move ions longitudinally through the apparatus for separation.

Garimella, Venkata B. S.↗

DOE OSTI2022

MOPED: An Alternative Workflow for HERON

MOPED is an alternate workflow to HERON. Preliminary tests display computational advantages of MOPED in terms of run time. While maintaining these advantages, solution convergence remained similar.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

DOE OSTI2022

Microgrid Training Session 5: Alternative Solutions to Microgrids

This presentation is the second session of a microgrid training series for the Air Force. Microgrids have advantages over other solutions; however, microgrids have their own costs in terms of finance and operations. This session will help attendees identify alternative solutions to specific issues.

Air Force↗

DOE OSTI2022

Multiplication of freestanding III-V semiconductor membranes from a single wafer by alternating growth with amorphous graphene interlayer

Freestanding single-crystalline III-V compound semiconductors are important building blocks for functional devices due to their high electron mobilities, a wide range of bandgaps, and excellent optoelectronic properties. Despite efforts to produce such membranes by detaching epitaxial layers from donor wafers, current methods suffer from either slow processes or poor material quality. Here, we demonstrate a technique to grow and harvest multiple epitaxial membranes with extremely high throughput at the wafer scale. For this, a process to directly grow amorphous graphene on III-V substrates in metal-organic chemical vapor deposition reactors is developed, which enables an advanced remote epitaxy scheme comprised of multiple alternating layers of amorphous graphene and III-V epitaxial layers that can be formed by a single epitaxy run. Each epilayer in the multi-stack structure is then harvested by layer-by-layer peeling, producing multiple freestanding membranes with unprecedented throughput from a single wafer. Because amorphous graphene provides a weak van der Waals interface that allows peeling at the interface without damaging the epilayer or the substrate, wafers can be reused for subsequent membrane production. Therefore, this work represents a meaningful step toward high-throughput and low-cost production of single-crystal membranes that can be heterointegrated.

Han, Ne Myo↗

DOE OSTI2023

Marine Alternative Fuel Pricing, Supply, and Demand

The International Maritime Organization low sulfur fuel rules and greenhouse gas-reduction strategy may create a significant perturbation to global refinery operations, impacting volumes and prices of marine fuel globally and within the United States and incentivizing the transition to alternative fuel use. The goals of this project are to (1) enhance understanding of how very low-sulfur fuel-primarily fuel oil and diesel-and low carbon fuel requirements and promising biofuel processes will affect the marine fuel supply chain; and (2) explore how these perturbations interact with and impact indicators such as pricing, number of trips, and demand behavior, along with the potential to meet low sulfur and carbon fuel demand with biofuel supply chains, (3) merge innovative thinking in the area of marine fuels within research centers of DOE (NREL) and the U.S. Department of Transportation (Volpe). These goals will be accomplished through the combination of detailed refinery, marine fuel burn, system dynamics, and geospatially explicit linear programming models.

biofuel↗

DOE OSTI2023

An Alternative to Solution Experiments for Nuclear Data Validation: Reflection and Interaction of Juxtaposed Uranium (RAIJU) Experiment Design

The need for solution experiments was thoroughly discussed at the recent NCERC (National Criticality Experiments Research Center) Futures Meeting in September 2022 for multiple applications including criticality safety, training, and nuclear data. However, this capability does not exist anywhere in the United States. NCERC, located at the Nevada National Security Site and operated by LANL (Los Alamos National Laboratory) is the only general-purpose critical experiments laboratory in the United States. However, solution experiments are not authorized at NCERC, and obtaining that authorization would be too time consuming and costly to happen in the foreseeable future. An alternative is needed – an experimental configuration with the homogeneity of liquid experiments, but without being a liquid. This project, Reflection and Interaction of Juxtaposed Uranium (RAIJU) will fill the gap in capability within LANL, the U.S. Department of Energy, and the international community and will support current and future nuclear material processing needs.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

DOE OSTI2023

Building Alternative Indices of Socioeconomic Status for Population Modeling in Data-Sparse Contexts (Short Paper)

Population modeling requires clear definitions of socioeconomic status (SES) to ensure overall estimate accuracy and locate potentially underserved subpopulations. This presents a challenge as SES can be measured in myriad ways and for divergent purposes, and the data required to calculate these metrics may be lacking, particularly in low and middle income countries (LMICs). To support more refined SES measurement, we explore improvements upon the Demographic and Health Survey’s (DHS) Wealth Index (DHS-WI) using alternative characterizations of SES based on multiple correspondence analysis (MCA) and hierarchical clustering. We produce the MCA-derived metrics first on a full suite of household economic, demographic, and dwelling variables, then on a reduced set of occupant-only SES characteristics. We explore the utility of these metrics relative to DHS-WI based on their ability to 1) differentiate DHS household types and 2) identify mixtures of SES levels within DHS samples and mapped at high spatial resolution. We find that our full suite MCA yields more clearly defined SES segments and that our reduced MCA delineates occupant SES most clearly, suggesting potential pathways to improve upon the DHS-WI in future population modeling efforts for LMICs.

Cunningham, Angela↗

DOE OSTI2023

Alternatives to Contour Visualizations for Power Systems Data

Electrical grids are geographical and topological structures whose voltage states are challenging to represent accurately and efficiently for visual analysis. The current common practice is to use colored contour maps, yet these can misrepresent the data. We examine the suitability of four alternative visualization methods for depicting voltage data in a geographically dense distribution system-Voronoi polygons, H3 tessellations, S2 tessellations, and a network-weighted contour map. We find that Voronoi tessellations and network-weighted contour maps more accurately represent the statistical distribution of the data than regular contour maps.

MATHEMATICS AND COMPUTING↗

DOE OSTI2023

Method and apparatus for ion mobility separations utilizing alternating current waveforms

Garimella, Venkata B. S.↗

DOE OSTI2015

French Atomic and alternative energies commission decommissioning policy and strategies: What is at stake lessons learned and feedback experience - 15013

Since its creation in 1945, the French Atomic Energy and Alternative Energies Commission has carried out research programmes on civil use of nuclear, and its application. CEA has set up and run various types of installations from research (accelerators, pond reactors, fast reactors, laboratories) to industry (power reactor, processing facilities). There are currently more than several tens of facilities which are presently closed down pending dismantling or in the process of being dismantled by CEA, the governmental body for research and development in nuclear and renewable energies. When operating, all these installations have generated radioactive waste. When they are shutdown, either as a result of the programmes for which they were set up, or due to equipment wearing out or being obsolete, these installations must be cleaned up, dismantled and decommissioned, taking into account their nuclear nature and requirements related to safety and environment. During the decommissioning process, the implementer has to deal with safety and site remediation issues. Dealing with these installations is a long-term programme which must be carefully planned and financed in order to optimise its management. The paper will describe the CEA's decommissioning policy, strategies adopted, and draw up lessons learned and feedback experience, showing that: - Safety is guaranteed, - Dismantling is a technically controllable operation, but R and D actions are to be developed for specific problems as characterization or operation in hostile environment. Moreover all the methods and techniques improve as a result of feedback experience, - The amount of material and waste produced by the dismantling are manageable. The very low, low and intermediate level waste can be stored on existing shallow land burial centres, some new repositories have to be created for specific waste (graphite, radium,...) and for high and intermediate level long live waste, which are stored in interim storage , - The dismantling must be optimized, especially by appliance of a good strategy based on rational industrial choices. - Communication and transparency with stakeholders is essential for global process acceptance, - The lessons learned and how feedback experience could benefit for future decommissioning projects. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2015

Evaluation of D and D alternatives for a DOE nuclear material processing facility - 15265

Ten scenarios for SRS Building 235-F were evaluated relative to groundwater protection through use of a 235-F GoldSim{sup TM} fate and transport model. The scenarios included two extreme scenarios, a no action scenario, four D and D grouting scenarios, and three D and D inventory removal scenarios. The fate and transport model simulated contaminant release from four 235-F process areas and the 294-2F Sand Filter and fate and transport through the vadose zone, the Upper Three Runs (UTR) aquifer, and the UTR creek. The model was a stochastic model for which 1,000 realizations were run over 100,000 years for each scenario. In association with the seven D and D alternatives only three groundwater standards out of 25 were exceeded, with the combined radium standard showing the greatest exceedance. The standards were only exceeded at the edge of the building after 10,000 years. It was estimated that there was a 90% likelihood that the combined radium standard would be exceeded for all four D and D grouting scenarios and that a 95% inventory removal from process cells 1-5 would result in an essentially zero percent likelihood that any standards would be exceeded. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2016

An Evaluation of Alternative Waste Management System Architectures - 16338

The Nuclear Fuels Storage and Transportation Planning Project (NFST), under the U.S. Department of Energy, Office of Nuclear Energy, Office of Fuel Cycle Technologies, is conducting analyses to inform future decisions regarding an integrated waste management system with a current focus on commercial spent nuclear fuel (SNF). This work builds on results from previous systems architecture studies within NFST. System-level analyses of the overall interface between at-reactor, consolidated storage, and ultimate disposition, along with the development of supporting logistic simulation tools, were initiated in 2012. This paper highlights recent results of the NFST systems architecture analysis efforts initiated in 2012. Waste management design choices are evaluated with respect to the impact on the entire system. This includes an analysis of alternative strategies for allocating receipt of SNF from reactor sites, storage options for SNF at an interim storage facility (ISF), and thermal limits restricting the transportation of canisters from an ISF to a mined geological repository (MGR). (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2019

Challenges of Maintaining Institutional Controls: Maintenance of an Alternate Water Supply- A Case Study - 19583

The US Department of Energy (DOE) cofunded an alternate water-supply system (AWSS) with the Indian Health Service that was installed in the vicinity of the former uranium mill site near Riverton, Wyoming, as one of the institutional controls (ICs) at the site. The AWSS was constructed in 1998 to supply drinking water to residents within the IC boundary in lieu of drinking untreated groundwater that could potentially be impacted by the contaminated shallow aquifer. The AWSS derives water from three source wells that pump groundwater from the sandstones of the Wind River Formation to a 3.8 x 106 liter (1,000,000 gallon) storage tank. Water from the storage tank is distributed throughout the AWSS service area by approximately 18 kilometers (11 miles) of PVC pipeline. The AWSS currently serves 103 residential customers and 1 commercial customer. DOE and the Northern Arapaho tribe (owner of the AWSS) have partnered over the years to address numerous challenges with the AWSS that included engineering assessments, scientific investigations, sampling support, a hydrant flushing program, and funding. Challenges with the AWSS have included the following: (1) Transmission pipe installed during initial construction did not have a pressure rating high enough to account for system pressure surges. (2) AWSS appurtenances were initially installed without accounting for the effects of corrosive soils on metal components. (3) Natural radium from the Wind River Formation groundwater builds up in the AWSS transmission pipes to levels above the primary drinking water standard because of the lack of a flushing program, dead-end lines, and low system demand. A 2-year study showed that a unidirectional hydrant-flushing program will control the radium buildup. (4) Aging system components including hydrants, valves, and pumps are nearing their effective lifespan and are in need of replacement. (5) With the addition of large commercial customers, demand on the system has increased since the initial installation of the system, and future growth in the area will continue to increase demand. (6) Additional connections and integration of the AWSS with an areawide water system in the near future will require changes to the current flushing plan and add additional complexity regarding areas of responsibility. (7) A well-organized financial and administrative infrastructure is not in place, and additional revenue is needed to operate, maintain, and improve the AWSS. To be a viable IC, the AWSS will require management, maintenance, and upgrades to provide safe drinking water until groundwater meets drinking water standards. Responsibilities and funding for maintaining the AWSS as a viable IC are the focus of current discussions, and decisions regarding responsibilities and funding will be formalized in future cooperative agreements and memoranda of understanding with the owners. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2020

Panel Session 98B: Treatment of Low-Activity Tank Waste at Hanford: Considering the Alternatives

This panel focused on alternative treatment of the Hanford Low-Activity Tank Waste. Currently, Tank Waste at the Hanford Site is to be separated into low-activity (LAW) and high-level waste (HLW) fractions, and then vitrified to produce immobilized LAW glass for onsite disposal, and HLW glass for ultimate geologic disposal. This panel discussed several commissioned studies by the National Laboratories, National Academies, and General Accountability Office to evaluate the risks, costs, and benefits associated with considering options for immobilizing portions of the Hanford LAW waste forms. Panelists with presentations: Analysis of Supplemental Treatment Approaches for Low-Activity Waste at the Hanford Nuclear Reservation Overview and Conclusions (Michael Stone); Analysis of Supplemental Treatment Approaches for Low-Activity Waste at the Hanford Nuclear Reservation: Disposal Performance Evaluation (Tom Brouns); National Academies Review of the Study on Supplemental Treatment Approaches of Low-Activity Waste at the Hanford Nuclear Reservation (Charles Ferguson); GAO Observations on Immobilizing Low-Activity Waste at DoE's Hanford Site (David Trimble)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2020

Alternative Treatment of Defense Waste Processing Facility Recycle via Reuse of Existing Liquid Waste Facilities - 20097

The Defense Waste Processing Facility (DWPF) at Savannah River Site (SRS) has been immobilizing high level waste since 1996. The chemical process within DWPF generates a large volume of condensate, which is recycled to the SRS H-Area Tank Farm. The recycle stream includes a small quantity of sludge solids, as well as soluble cesium that is volatilized during melter operation. The recycle waste is currently received into a large, underground waste tank that separates insoluble solids via decanting. The supernate is treated by an evaporator with a concentrate stream that is stored for future processing. The evaporator overheads are collected and sent to the Effluent Treatment Project (ETP) for final polishing and testing prior to discharge to local surface water. Recycle storage and treatment as described above complicates the overall mission within the tank farms, which are primarily engaged in waste retrieval and preparation activities that support sludge and salt disposition, as well as tank characterization and closure. The need to devote a portion of available storage space to recycle treatment limits operational flexibility, and ultimately the DWPF recycle stream must be diverted to fully close all the SRS waste tanks. An alternative treatment process is being explored to decouple the recycle stream from the tank farm. The proposed treatment process will accomplish solids separation via crossflow filtration and will utilize a wiped film evaporator to volume-reduce the filtrate stream. Evaporator overheads will continue to be further processed in ETP while the solids stream and evaporator concentrate stream will be returned for reprocessing with the DWPF and Salt Waste Processing Facility (SWPF). This process will utilize existing facilities within DWPF and the tank farm that were previously dedicated to Interim Salt Disposition (ISD), but no longer have an identified mission with the startup of SWPF. The reuse of these facilities will remove several constraints from the current Liquid Waste (LW) System Plan without expanding the current footprint of Department of Energy Environmental Management (EM) infrastructure within LW. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2017

Development of the Delphi display concept for alternative explanations decision making support - 120

Human operators of advanced technology systems, such as nuclear power, command and control, and deepwater oil drilling, must be able to evaluate and respond to a wide array of operational anomalies. Unfortunately, these circumstances are often complex and ambiguous, complicating decision making tasks. One common decision making error, called confirmation bias, occurs when decision makers prematurely focus on one explanation instead of systematically considering all plausible alternative explanations that could equally well account for an operational anomaly (Nickerson, 1998). The Delphi display is designed to counteract decision makers' tendencies towards confirmation bias and to encourage them to consider all plausible explanations, including high risk explanations, they might otherwise overlook. An initial Delphi display prototype was designed to help identify the underlying cause of operational anomalies in the complex, high-consequence technology of deepwater drilling. This prototype decision aid incorporates major indicators related to operational anomalies and presents corresponding plausible explanations for each indicator, ranging from high-risk system-critical explanations to lower-risk but still significant events. The Delphi display incorporates several innovative features to help decision makers detect and monitor operational anomalies and view the relationships among indicators and their associated plausible explanations. Preliminary evaluations of an early prototype Delphi display for detecting kicks in deepwater oil drilling operations have been promising. Moreover, the methodology used to design and develop the Delphi display can be readily generalized to numerous other operational contexts that require humans to make system-critical decisions. To illustrate, an initial Delphi display design for nuclear power plant control is described. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗