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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

In-Vehicle Assessment of Human Exposure to Electromagnetic Fields from 25-kW Wireless Power Transfer System Based on Near-Field Analysis

Wireless power transfer (WPT) technology has the potential to be a convenient and reliable charging method for the light and heavy duty electric vehicles. However, the loose coupling between the two sides results in strong near-electromagnetic fields (EMFs) around the system, which may have the possibility to impact human safety if the standard limits are exceeded. Therefore, comprehensive tests are necessary to ensure the electromagnetic fields are with in safe limits. This paper presents a test methodology for the near-field from a 25-kW WPT system from Momentum Dynamics, which is installed in a heavy-duty electric shuttle at the National Renewable Energy Laboratory (NREL). The paper describes in detail the measuring device, test setup, and conditions.

30 DIRECT ENERGY CONVERSION↗
DOE OSTI2019

Electromagnetic launcher with circular guideway

An electromagnetic launcher with a closed-loop guideway and conductors for launching a projectile. The projectile is accelerated along the guideway using electromagnetic forces until it reaches a desired speed, then the projectile is launched in a desired direction. The direction of the launch of the projectile is determined by orienting the guideway in the desired direction using an actuator. The guideway may include a door or aperture allowing the projectile to be launched therefrom, tangent to the curvature of the guideway.

42 ENGINEERING↗
DOE OSTI2019

Electromagnetic launcher with circular guideway

An electromagnetic launcher with a closed-loop guideway and conductors for launching a projectile. The projectile is accelerated along the guideway using electromagnetic forces until it reaches a desired speed, then the projectile is launched in a desired direction. The direction of the launch of the projectile is determined by orienting the guideway in the desired direction using an actuator. The guideway may include a door or aperture allowing the projectile to be launched therefrom, tangent to the curvature of the guideway.

42 ENGINEERING↗
DOE OSTI2021

Electromagnetic launcher with spiral guideway

An electromagnetic launcher with a curved or spiral-shaped, open-ended guideway and conductors for launching a projectile. The projectile, movably retained on or within the guideway, is accelerated along the guideway using electromagnetic forces until it reaches an end of the guideway, then the projectile is launched in a desired direction. The direction of the launch of the projectile is determined by orienting the guideway in the desired direction using an actuator.

Hartman, Seth↗
DOE OSTI2021

Electromagnetic launcher with spiral guideway

An electromagnetic launcher with a curved or spiral-shaped, open-ended guideway and conductors for launching a projectile. The projectile, movably retained on or within the guideway, is accelerated along the guideway using electromagnetic forces until it reaches an end of the guideway, then the projectile is launched in a desired direction. The direction of the launch of the projectile is determined by orienting the guideway in the desired direction using an actuator.

Hartman, Seth↗
DOE OSTI2010

Nuclear Electromagnetic Currents in Chiral Effective Field Theory

We have derived nuclear electromagnetic currents in chiral effective field theory with pions and nucleons as explicit degrees of freedom. The calculation has been carried out in time-ordered perturbation theory up to include N$^3$LO corrections, consisting of two--pion exchange, and contact contributions. Here I will present our calculation and discuss the results obtained for a number of electromagnetic observables of $A\leq4$ nuclei.

Pastori, Saori↗
DOE OSTI2023

An Overview of the Radioisotope Electromagnetic Isotope Separation Capabilities at Idaho National Laboratory

Electromagnetic isotope separation (EMIS) has been an effective tool for the enrichment of isotopes for over 80 years. In the early 1990’s the U.S. reduced or eliminated electromagnetic isotope separation capabilities, but in the last decade, increased demand for both stable and radioactive enriched isotopes have led to the reestablishment of small-medium scale EMIS capabilities in the U.S. National Laboratory Complex.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2023

System and method using in-situ electromagnetic diagnostic for real-time projectile characterization

The present disclosure relates to a system for detecting characteristics of a moving element. The system may include a tubular housing having a tubular first portion having a first end and a second end, with the first end forming an input port and the second end forming an output port. A source of wireless electromagnetic energy projects a wireless electromagnetic energy signal, travelling in a first direction, into the input port and through an interior area defined by the tubular first portion. A signal processing subsystem detects at least one characteristic of the signal after the signal is reflected back to the first end after having interacted with the element as the element moves past the output port of the housing.

Chang, Tammy↗
DOE OSTI2017

Implementation of wireless technologies in nuclear power plants' electromagnetic environment using cognitive radio system - 153

Wireless technologies have increased efficiency in many industrial settings across the world by enabling a mobile workforce and improving communications. Unfortunately, the nuclear power industry has been slow to adopt wireless technology as a result of safety, security, and reliability concerns expressed by regulators and others. A Research and Development (R and D) effort is currently being conducted to address two significant technical concerns for the introduction of wireless technology in nuclear power plants, which are electromagnetic compatibility (EMC) and wireless coexistence. Most equipment in nuclear power plants has never been tested for vulnerability to wireless transmission. As such, the impact of modern wireless devices on nuclear safety and plant reliability is not understood. Existing guidance from the Nuclear Regulatory Commission (NRC) and Electric Power Research Institute (EPRI) rely on the use of exclusion zones to protect plant equipment, which can result in exclusion zones of up to eight feet for some tablet devices rendering them ineffective for the mobile workforce. Another unknown is how different wireless devices will operate in close proximity to one another in the harsh electromagnetic environment of a nuclear power plant. These issues are being addressed through development of a cognitive radio system that has the ability to generate and output multiple wireless signals such as Wi-Fi, Bluetooth, and cellular communications at varying power levels and frequencies. The cognitive radio system is a modular system that can test nuclear plant equipment located in training areas, simulators, and the actual plant environment. In addition to using the system for testing plant equipment to wireless signals and EMC standards, the system can also monitor the radio spectrum for usage in other plant focuses such as cyber security. The R and D work will provide the objective guidance for the nuclear industry in the two areas mentioned and will develop a cognitive radio system for in-plant EMC and coexistence testing. The system will assist in the seamless use of wireless technology in nuclear power plants while greatly reducing the risks wireless signals may introduce. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2024

Measurement of the Neutron Electromagnetic Form Factor Ratio at High Momentum Transfer

The inner structure of the nucleon (proton and neutron) remains a topic of great interest in nuclear and particle physics, after many decades of study. For example, understanding the quark-gluon dynamics inside the nucleon would shed light on how 99% of the nucleon mass is created. The neutron electromagnetic form factors, Gn E and Gn M , give important insights into the neutron structure. The Super BigBite Spectrometer (SBS) program at Jefferson Lab (JLab) seeks to extend the form factor measurements for both the proton and the neutron. The neutron electric form actor, Gn E , has been historically difficult to measure due to the short lifetime of the free neutron and the small value of Gn E . The GEn-II experiment is part of the SBS program and seeks to measure Gn E , significantly increasing the high momentum transfer coverage. A newly designed polarized 3He target increased the figure of merit by three times compared to previous measurements. The analysis of this data is especially challenging due to the unprecedented high-rate environment caused by the open nature of the spectrometer with a direct line of sight to the target. This required developing new Gas Electron Multiplier (GEM) particle trackers which can cover large areas demanded by this setup and handle particle rates up to 500 kHz/cm2. Rates this high over a large area is unprecedented in particle tracking systems and came with a number of challenges. Data taken in the SBS program was critical to understanding hardware and software solutions that improved the track reconstruction efficiency to be >97% with a position resolution of 70 ?m. In previous experiments the proton electromagnetic form factors, Gp E and Gp M were measured up to Q2 = 8.5 GeV2 and Q2 = 30 GeV2, respectively, while Gn E has only been measured up to Q2 = 3.4 GeV2. The GEn-II experiment has measured the neutron form factor ratio, Gn E/Gn M, at Q2 values of 2.90, 6.50, and 9.47 GeV2 by scattering a polarized electron beam with a polarized 3He target, used here as an effective polarized neutron target, and measuring the double spin asymmetry of the cross section. Previous Gn E measurements do not extend above Q2 = 3.4 GeV2, and therefore this analysis has extended the world data by almost three times. The background correction is especially difficult at the higher Q2 settings leading to large systematic errors. As very exploratory results from this early analysis of the data, we find for Q2 = 2.90 GeV2, Gn E = 0.0157 ±stat 0.0016 ±sys 0.0011, for Q2 = 6.50 GeV2, Gn E = 0.0067 ±stat 0.0019 ±sys 0.0005, and for Q2 = 9.46 GeV2, Gn E = 0.0046 ±stat 0.0023 ±sys 0.0005. These results are compared to predictions from the Dyson-Schwinger Equations (DSE) model and a Relativistic Constituent Quark Model (RCQM).

Jeffas, Sean↗
DOE OSTI2024

Electromagnetic field-assisted method for chemical conversion

Embodiments relate to methods for enhancing chemical conversions. One or more embodiments relate to a method for enhancing a multi-step chemical conversion reaction. The method includes providing a reactant mixture comprising one or more reacting specie(s); and providing a catalyst or sorbent comprising one or more support materials and one or more deposited catalytically active materials. The method further includes applying an electromagnetic field with a prescribed power, frequency, and pulsing strategy specific to interactions of reactant species and an electromagnetic field with at least one of the support materials, sorbent, and catalytically active materials in a particular chemical reaction.

Shekhawat, Dushyant↗
DOE OSTI2024

Adaptive materials and systems for manipulation of electromagnetic radiation

Fully artificial, adaptive composite materials and systems, having variable transmittance, reflectance, and/or absorptance to radiation in visible, infrared, or other desired region of the electromagnetic spectrum, and methods of the manufacture and use thereof are provided. The adaptive composite materials and systems possess an unprecedented combination of properties and are, therefore, poised to enable a broad range of practical applications. The adaptive composite material incorporates at least one size-variable active area having a variable transmittance, reflectance, and/or absorptance in at least a portion of the electromagnetic spectrum and comprises at least: an elastomer substrate, a texturizing layer disposed on top of the substrate, and an optional reflective coating disposed on top of the texturizing layer. In operation, the stretching and relaxation of the elastomer substrate causes changes in the surface morphology of the texturized layers (e.g., the change in the size and depth of surface features in the texturizing layer), this in turn results in the increased or decreased transmittivity, reflectivity, and/or absorptivity of the active area.

Gorodetsky, Alon A.↗
DOE OSTI2025

Opportunities and Challenges of Computational Electromagnetics Methods for Superconducting Circuit Quantum Device Modeling: A Practical Review

High-fidelity numerical methods that model the physical layout of a device are essential for the design of many technologies. For methods that characterize electromagnetic effects, these numerical methods are referred to as computational electromagnetics (CEM) methods. Although the CEM research field is mature, emerging applications can still stress the capabilities of the techniques in use today. The design of superconducting circuit quantum devices falls in this category due to the unconventional material properties and important features of the devices covering nanometer to centimeter scales. Such multiscale devices can stress the fundamental properties of CEM tools which can lead to an increase in simulation times, a loss in accuracy, or even cause no solution to be reliably found. While these challenges are being investigated by CEM researchers, knowledge about them is limited in the broader community of users of these CEM tools. This review is meant to serve as a practical introduction to the fundamental aspects of the major CEM techniques that a researcher may need to choose between to model a device, as well as provide insight into what steps they may take to alleviate some of their challenges. Our focus is on highlighting the main concepts without rigorously deriving all the details, which can be found in many textbooks and articles. After covering the fundamentals, we discuss more advanced topics related to the challenges of modeling multiscale devices with specific examples from superconducting circuit quantum devices. We conclude with a discussion on future research directions that will be valuable for improving the ability to successfully design increasingly more sophisticated superconducting circuit quantum devices. Although our focus and examples are taken from this area, researchers from other fields will still benefit from the details discussed here.

Elkin, Samuel T. [Virginia Tech., Blacksburg]↗
DOE OSTI2024

A novel A-ϕ formulation for efficient electromagnetic computations

In numerical simulation of electromagnetic prob- lems, potential-based formulations have advantages over field- based formulations because of their immunity to the low- frequency breakdown catastrophe. Recently, an all-frequency stable formulation has been proposed to solve electromagnetic problems in a wide frequency band. This formulation employs magnetic vector and electric scalar potentials, as well as an auxiliary potential to enforce an inhomogeneous Coulomb gauge. However, such a three-potential formulation has encountered convergence issues at low frequencies. To avoid the convergence issue and improve computational efficiency, a novel formulation with only two potentials and an implicit Coulomb gauge is proposed in this paper. A numerical example is presented to show its solution accuracy and computational efficiency.

Mekonnen, Minyechil↗
DOE OSTI2011

Causal electromagnetic interaction equations

For the electromagnetic interaction of two particles the relativistic causal quantum mechanics equations are proposed. These equations are solved for the case when the second particle moves freely. The initial wave functions are supposed to be smooth and rapidly decreasing at the infinity. This condition is important for the convergence of the integrals similar to the integrals of quantum electrodynamics. We also consider the singular initial wave functions in the particular case when the second particle mass is equal to zero. The discrete energy spectrum of the first particle wave function is defined by the initial wave function of the free-moving second particle. Choosing the initial wave functions of the free-moving second particle it is possible to obtain a practically arbitrary discrete energy spectrum.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2011

Charged particle motion in electromagnetic fields varying moderately rapidly in space

Electromagnetic fields are considered which vary on the space scale of the geometric mean of the Larmor radius and the much larger scale length of variation of the magnetic field lines. It is first shown that the magnetic moment is an adiabatic invariant, even though the usual arguments for its existence fail. The motion of the guiding center is then examined. For perpendicular drifts in magnitude comparable with the particle speed, the subsequent motion is dominated by electrostatic effects. The motion of particles along the field lines occurs on a much slower time scale than the perpendicular drift time scale. When the guiding center motion is approximately periodic in time, a second adiabatic invariant exists, the magnetic flux enclosed by the almost periodic orbit. When the perpendicular drift is small compared with the particle speed, the parallel motion and the perpendicular drift occur on the same, slow timescale.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2013

Enhanced nonlinear interaction of powerful electromagnetic waves with ionospheric plasma near the second electron gyroharmonic

Plasma experiments in which a powerful electromagnetic pump wave is transmitted into the ionosphere from the ground give access to a rich range of phenomena, including gyroharmonic effects when the pump frequency is near an harmonic of the ionospheric electron gyrofrequency. For pump frequencies close to the second gyroharmonic, experiments show a strong enhancement, as observed in radar scatter from pump-induced geomagnetic field-aligned density striations and optical emissions. This is in contrast to the case at the third harmonic and higher at which most of the effects are instead suppressed. We show theoretically that electrostatic oscillations can be localized in density inhomogeneities associated with small scale striations. The localized field is a mixture of the electron Bernstein and upper hybrid modes when the pump frequency is near the second gyroharmonic. The coupling of the modes is enabled by a symmetry feature of the linear electron Bernstein and upper hybrid dispersion properties that occur only near the second gyroharmonic. Electron acceleration inside the density inhomogeneities by localized azimuthal electrostatic oscillations is more efficient near the second gyroharmonic than at higher frequencies, consistent with the observed enhancements.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2021

Dispersion relation for gauge-free electromagnetic drift kinetics

Recently, a new approach to gyrokinetics, invariant under electromagnetic gauge transformations, was developed. The gyrocenter equations of motion are now expressed in terms of the perturbed fields instead of the potentials, in a form suitable for numerical simulations and analytic studies. In this paper, we verify that the long-wavelength limit, i.e., the drift-kinetic limit of the new gyrokinetic theory, is in line with existing work, providing a solid foundation for simulations. Here, we compute the dispersion relation of the new drift-kinetic theory in slab geometry and find agreement with a long-wavelength limit of the full Vlasov–Maxwell model.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗