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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 1,729 records · Page 96
All sourcesNASA NTRSDOE OSTI
DOE OSTI2015

Simulation of beam-induced plasma for the mitigation of beam-beam effects

One of the main challenges in the increase of luminosity of circular colliders is the control of the beam-beam effect. In the process of exploring beam-beam mitigation methods using plasma, we evaluated the possibility of plasma generation via ionization of neutral gas by proton beams, and performed highly resolved simulations of the beam-plasma interaction using SPACE, a 3D electromagnetic particle-in-cell code. The process of plasma generation is modelled using experimentally measured cross-section coefficients and a plasma recombination model that takes into account the presence of neutral gas and beam-induced electromagnetic fields. Numerically simulated plasma oscillations are consistent with theoretical analysis. In the beam-plasma interaction process, high-density neutral gas reduces the mean free path of plasma electrons and their acceleration. A numerical model for the drift speed as a limit of plasma electron velocity was developed. Simulations demonstrate a significant reduction of the beam electric field in the presence of plasma. Preliminary simulations using fully-ionized plasma have also been performed and compared with the case of beam-induced plasma.

43 PARTICLE ACCELERATORS↗
DOE OSTI2014

Dynamical QCD+QED simulation with staggered quarks

Electromagnetic effects play an important role in many phenomena such as isospin-symmetry breaking in the hadron spectrum and the hadronic contributions to g-2. We have generalized the MILC QCD code to include the electromagnetic field. In this work, we focus on simulations including charged sea quarks using the RHMC algorithm. We show details of the dynamical QCD+QED simulation algorithm with compact QED. We analyze the code performance and results for hadron-spectrum observables.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2017

Perpendicular momentum input of lower hybrid waves and its influence on driving plasma rotation.

The mechanism of perpendicular momentum input of lower hybrid waves and its influence on plasma rotation are studied. Discussion for parallel momentum input of lower hybrid waves is presented for comparison. It is found out that both toroidal and poloidal projections of perpendicular momentum input of lower hybrid waves are stronger than those of parallel momentum input. The perpendicular momentum input of lower hybrid waves therefore plays a dominant role in forcing the changes of rotation velocity observed during lower hybrid current drive. Lower hybrid waves convert perpendicular momentum carried by the waves into the momentum of dc electromagnetic field by inducing a resonant-electron flow across flux surfaces therefore charge separation and a radial dc electric field. The dc field releases its momentum into plasma through the Lorentz force acting on the radial return current driven by the radial electric field. Plasma is spun up by the Lorentz force. An improved quasilinear theory with gyro-phase dependent distribution function is developed to calculate the radial flux of resonant electrons. Rotations are determined by a set of fluid equations for bulk electrons and ions, which are solved numerically by applying a finite-difference method. Analytical expressions for toroidal and poloidal rotations are derived using the same hydrodynamic model.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2017

Reactive polymer fused deposition manufacturing

Methods and compositions for additive manufacturing that include reactive or thermosetting polymers, such as urethanes and epoxies. The polymers are melted, partially cross-linked prior to the depositing, deposited to form a component object, solidified, and fully cross-linked. These polymers form networks of chemical bonds that span the deposited layers. Application of a directional electromagnetic field can be applied to aromatic polymers after deposition to align the polymers for improved bonding between the deposited layers.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Beam position monitor for energy recovered linac beams

A method of determining the beam position in an energy recovered linac (ERL). The method makes use of in phase and quadrature (I/Q) demodulation techniques to separate the pickup signal generated by the electromagnetic fields generated by the first and second pass beam in the energy recovered linac. The method includes using analog or digital based I/Q demodulation techniques in order to measure the relative amplitude of the signals from a position sensitive beam pickup such as a button, strip line or microstripline beam position monitor.

47 OTHER INSTRUMENTATION↗
DOE OSTI2017

Chip-based droplet sorting

A non-contact system for sorting monodisperse water-in-oil emulsion droplets in a microfluidic device based on the droplet's contents and their interaction with an applied electromagnetic field or by identification and sorting.

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

Comparison of 22 kHz and 85 kHz 50 kW Wireless Charging System Using Si and SiC Switches for Electric Vehicle

Fast charging in transportation application requires high-power (>50 kW) operation. The overall size of wireless charging systems (WCS) must increase to meet the high-power requirement. As a result, high power systems produce more electromagnetic field (EMF) emissions. Although higher operating frequencies (85 kHz) reduce the size of inductors and capacitors, system losses tend to increase. High-power systems are traditionally investigated for 10 kHz to 22 kHz operation to reduce the switching loss in the converter, and conductive and magnetic losses in the power pad. The use of SiC MOSFETs reduces conduction and switching losses in the converter even at higher frequencies. In this paper, a comprehensive loss comparison of 50 kW wireless charging system is conducted for 85 kHz and 22 kHz operation of Si MOSFET and SiC MOSFET converters. Detailed performance indexes are compared analytically as a function of frequency and verified using FEA and PLECS. This comprehensive system level study shows that magnetic losses can be reduced significantly, and that EMF emission can be reduced by 50% by moving from 22 kHz to 85 kHz. Moreover, the system requires 50% less copper and allows a significant reduction in the size of the primary and secondary filter capacitor at 85 kHz. The results show that the system efficiency at 85 kHz can be increased by 21% compared to 22 kHz operation by using a SiC MOSFET converter.

Shahidul haque, Moinul↗
DOE OSTI2019

Human Exposure Analysis to EMFs from Ground Assembly of a WPT System During the Vehicle's Non-Attendance

This presentation presents assessment analysis for the human exposure to electromagnetic fields (EMFs) from the ground assembly of the wireless power transfer (WPT) before alignment, while the vehicle does not exist over the pad. A 25-kW WPT system from Momentum Dynamics is analyzed using finite-element software during the low power alignment operation. The same system is installed at the National Renewable Energy Laboratory and tested at the same conditions. Good agreement is observed between the results. In addition, both results comply with standard exposure limits.

30 DIRECT ENERGY CONVERSION↗
DOE OSTI2019

Passive Absorbers for Maximizing the Performance of the Mu2e-II Experiment

The Fermilab’s Mu2e experiment is designed to search for Charged Lepton Flavour Violation in direct, neutrinoless conversion of a muon into an electron in the presence of a nuclear electromagnetic field. The quantity, which is observed is the ratio between the rate of the above BSM (Beyond Standard Model) conversion reaction and the rate of muon capture on the nucleus. The measurement precision is expected to reach up to 10 -17 [1]. Mu2e-II is the name for the second phase of the experiment, which is planned to run with the lower energy, higher intensity primary proton beam provided by the PIP-II [2] accelerator, currently under construction. Ionization cooling with a wedge absorber is introduced into Mu2e-II setup to potentially increase the number of low momentum muons reaching the target. A study is made into the position and size of the wedge inside the beamline using G4Beamline simulation framework. Results show an increase up to 12% for muons with momentum P below 30 MeV/c and 7% for muons with P <40 MeV/c when the beam is measured right after the wedge. Further studies are necessary to investigate how this gain can be delivered to the stopping target.

43 PARTICLE ACCELERATORS↗
DOE OSTI2019

Capacitance-Based Dimensional Change Sensors for In-Pile Materials Measurements

Advanced fuel compositions, such as accident tolerate fuels (ATF), are an active area of developing in the nuclear power industry. The long-term performance of these newly developed fuels is estimated through physics-based simulation models of irradiation-, temperature-, pressure-, etc.-induced material degradation. As these fuels are deployed in test reactors, measurement and characterization of the fuel pin evolution is used to validate prediction models. In-pile material evolution parameters, such as fuel rod pressurization, fuel stack and cladding elongation, and cladding diameter, are commonly measured using a linear voltage differential transformer (LVDT). However, LVDTs are bulky and limited to lower (350-500C) temperature operation. The high power density and small size of most experimental positions in high performance research reactors used for accelerated materials irradiation studies generally precludes the use of LVDTs in these reactors. There is a critical need for sensors that provide real-time data regarding material evolution under highly accelerated irradiation. These sensors would ideally have a small profile and the ability to withstand irradiation at extremely high dose rates and temperatures for extended periods of time. A capacitance-based sensor is currently under development at the University of Tennessee to provide a direct measurement of in-pile dimensional change during irradiation. Sensor response was simulated using AutoCAD Electromagnetic field simulator (EMS) for a variety of sensor materials and configurations and fuel pin swelling conditions. Initial results of these simulations are summarized and areas of ongoing research and development are discussed.

Naughton, Tyler↗
DOE OSTI2018

Innovative nanopore sequencing technology including a self-assembled porous membrane

Methods and apparatus for long read, label-free, optical nanopore long chain molecule sequencing. In general, the present disclosure describes a novel sequencing technology based on the integration of nanochannels to deliver single long-chain molecules with widely spaced (>wavelength), ˜1-nm aperture “tortuous” nanopores that slow translocation sufficiently to provide massively parallel, single base resolution using optical techniques. A novel, directed self-assembly nanofabrication scheme using simple colloidal nanoparticles is used to form the nanopore arrays atop nanochannels that unfold the long chain molecules. At the surface of the nanoparticle array, strongly localized electromagnetic fields in engineered plasmonic/polaritonic structures allow for single base resolution using optical techniques.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Defeat system for vehicle attached improvised explosive devices

An explosive device detection and expulsion system broadly comprising a detection subsystem for sensing an IED attached to a vehicle and an expulsion subsystem for expelling the IED from the vehicle. The detection subsystem includes a sensor for detecting an IED via an electromagnetic field change or capacitance change, vibrations, and/or heat, and a controller for activating the expulsion subsystem upon receiving a detection signal from the sensor. The expulsion subsystem includes a deployable panel configured to be attached to the vehicle and a deployable mechanism for shifting the deployable panel from an undeployed state to a deployed state so as to expel the IED from the vehicle.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2019

Lighting system with induction power supply

A system for producing light is provided. The system comprises a sealed enclosure surrounding a porous graphite foam conductor which is exposed to an electromagnetic field generated by an oscillating circuit. When exposed, the foam conductor conducts induced electric current which heats the same to product light. The amount of light is controllable by changing the output of a drive circuit. The oscillating circuit comprises a first inductor and a first capacitor. The first inductor has a first terminal and a second terminal. The output of the drive circuit is controlled by turning a MOSFET OFF and ON. The MOSFET is turned ON when an integrated signal representative of a difference between a voltage proportional to the first terminal and a voltage proportional to the second terminal is between a first voltage threshold and a second voltage threshold and based on a timing signal.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2021

Defeat system for vehicle attached improvised explosive devices

An explosive device detection and expulsion system broadly comprising a detection subsystem for sensing an IED attached to a vehicle and an expulsion subsystem for expelling the IED from the vehicle. The detection subsystem includes a sensor for detecting an IED via an electromagnetic field change or capacitance change, vibrations, and/or heat, and a controller for activating the expulsion subsystem upon receiving a detection signal from the sensor. The expulsion subsystem includes a deployable panel configured to be attached to the vehicle and a deployable mechanism for shifting the deployable panel from an undeployed state to a deployed state so as to expel the IED from the vehicle.

Hower, Brent↗
DOE OSTI2021

Coupling Finite Element and Finite Volume Simulation Within MOOSE

This work focuses on adding capability to couple finite element (FE) variables into finite volume (FV) physics within INL’s Multiphysics Object-Oriented Simulation Environment (MOOSE). This coupling can allow for improvement of multiphysics simulations where one set of physics is best suited for an FE discretization, while another set is best suited for an FV discretization. Electrohydrodynamics, which govern liquid metal reactor concepts and plasma dynamics, is a fitting example where the electromagnetic field equations are solved with FE and the fluid flow is solved with FV. The new FE to FV coupling method can be summarized as taking the element or face average of the FE variable value or gradient and applying that quantity directly in the FV equation objects.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2021

Innovative nanopore sequencing technology including a self-assembled porous membrane

Methods and apparatus for long read, label-free, optical nanopore long chain molecule sequencing. In general, the present disclosure describes a novel sequencing technology based on the integration of nanochannels to deliver single long-chain molecules with widely spaced (>wavelength), ˜1-nm aperture “tortuous” nanopores that slow translocation sufficiently to provide massively parallel, single base resolution using optical techniques. A novel, directed self-assembly nanofabrication scheme using simple colloidal nanoparticles is used to form the nanopore arrays atop nanochannels that unfold the long chain molecules. At the surface of the nanoparticle array, strongly localized electromagnetic fields in engineered plasmonic/polaritonic structures allow for single base resolution using optical techniques.

Brueck, Steven R. J.↗
DOE OSTI2021

Moving from scientific research to consenting guidance for MRE environmental risk

Potential environmental effects from tidal and wave devices are of concern to regulators, advisors, and other stakeholders in many nations. Monitoring results from early deployments and the first commercial arrays, coupled with targeted research studies, are providing a growing base of knowledge of how components of tidal turbines and wave energy converters might interact with marine animals and habitats. Efforts are underway to organize and direct these findings towards facilitating consenting that allays concerns and allows the marine renewable energy (MRE) industry to move forward. The OES-Environmental international initiative has developed scientific evidence bases for several key interactions from MRE devices, organized around stressors (portions of MRE systems that may cause injury or stress to the marine ecosystem), and receptors (the animals, habitats, and ecosystem processes that may be affected). This paper summarizes the evidence bases for four stressors (underwater noise, electromagnetic fields, habitat change, and changes in oceanographic systems) and presents the process of moving from the scientific knowledge into guidance documents to support the regulatory process. The guidance documents will serve as a broad guide that can be used internationally to look at stressor-receptor interactions of interest within a regulatory context. The evidence bases and guidance documents aim to assist MRE developers, regulators, and advisors with project scoping, consenting, and licensing processes.

Copping, Andrea E.↗
DOE OSTI2021

Increase resistance for efficient heating

Conductors for use in heating systems are provided. The conductors are configured to have an extended current path for the current and increased resistance as seen by the current. The heating system may be an induction system. For example, the conductor may comprise a conductive material having a surface which faces an induction coil of an oscillating circuit. This surface may have a predetermined pattern of peaks and valleys. The peaks and valleys form a non-linear current path for the induced current when exposed to an electromagnetic field generated by the oscillating circuit. Other conductors such as a heat pipe may be used. The pipe may have walls with varying thicknesses over its length. The varying thicknesses may include a first thickness and a second thickness which alternate. The heat pipe may be used in an induction or direct contact heating system where AC is directly applied to the pipe.

Kisner, Roger A.↗