SEARCH · Engineering Papers
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.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
A non-magnetic insert will be placed directly inside the permanent magnet blocks in every CBETA Halbach magnet in order to hold a set of iron “tuning wires”. These wires have various lengths around the perimeter of the aperture in order to cancel multipole field errors from the permanent magnet blocks.
Project highlight. This project designs and implements a new additive manufacturing capability at Savannah River National Laboratory. Wire Arc Additive Manufacturing is an Advanced Manufacturing technology that enables materials and energy savings by producing materials that are in near net shapes to minimize material losses compared to conventional forging and machining techniques. Wire arc additive manufacturing is an evolving technology that can be used to fabricate large components with significantly less materials waste than conventional processing. This project includes an engineering model, an aspect that is largely overlooked in the Additive Manufacturing modeling work where the emphasis has been on mechanistic and microscopic modeling, to estimate the residual stresses and distortions. The Abaqus Weld Interface software coupled with user subroutines in Fortran enable the local cooling rates to be estimated to provide a coarse scale model for the secondary dendrite arm spacing, a parameter useful to estimate mechanical properties.
Methods of simulating the electrical characteristics of exploding bridge-wire detonators using only inert materials are reported. Specifically, it is found that both pressed finely powdered sucrose (confectioners sugar) and 3 µm aluminum oxide powder match the signals measured in a real EBW detonator with PETN fill. The exact pressing density of the inert powder is found not to affect to the measured electrical signals. Additionally, the action-integral (the time integral of bridge current squared) and energy-to-burst are measured for the same gold bridge design with several capacitor discharge units at different charge voltages and inductances as well as pseudo-constant current fireset made from charged coaxial-cables. It is found that in contrast to some reports, the action-integral to burst is not a constant for a specific bridge geometry and material, but instead is a function of the rate of current change in the bridge around the time of burst. This is explained by the confining effects of bridge-wire inertia affecting the rapid expansion of the bridge around burst time and hence the dynamic resistance.
High field magnets are needed for frontier accelerator facilities and have many applications beyond high-energy physics. Of particular interest are 30-40T class (LTS/HTS hybrid) solenoids required for the final beam cooling stages of a muon collider facility. The successful design of such magnets using Bi2212 conductor depends critically on the conductor processing, stress management in the coil, and quench protection. These are the challenges addressed in the proposal and the overall objectives of the combined Phase I and Phase II projects. Bi2212 round wire conductor will be evaluated for accelerator use by concentrating on the design of a solenoid magnet that will be the enabling technology for realizing the final stages of muon beam cooling and thus a high luminosity muon collider. A full mechanical characterization of a test coil made from overpressure-processed conductor with engineering current density JE in the range of & gt;600 A/mm2 at 20-30 T will be performed. The data from the test coil will serve as input to a 30+ T magnet that will be designed, built, and tested to demonstrate the suitability of overpressure-processed Bi2212 for solenoids for final muon cooling and 6D cooling channels. Short lengths and coils wound from up to 100 m length conductor will be overpressure processed. Characterization of an overpressure processed Bi2212 round-wire based solenoid will be performed at 4.2 K in a background field of up to 14 T. The characterization will include mechanical, thermal, and quench properties. The data will be used as input to a 30+ T coil design that has suitable stress management and quench protection, to be built and tested in Phase II. Commercial applications and other benefits: The technology developed by this work will benefit high-energy physics applications. The knowledge and expertise gained from this project will enable the development of very high-field solenoids, dipoles, and quadrupoles using Bi2212 cable at low temperature for applications in future particle accelerators. The technology will also extend the range available to Nuclear Magnetic Resonance Spectroscopy, an important technique used to understand molecular structures of proteins and other materials.
X-pinches are a pulsed power wire-array configuration that produce nanosecond and micron-scale X-ray sources with numerous applications. The earliest embodiment of the X-pinch inspired its name, as it is typically composed of two or more fine (5-50 µm) wires crossed into the shape of an X (Fig. 1a). The ‘X’ ablates when subjected to large (10 1 -10 4 kA), fast-rising (~1 kA/ns) currents, and extreme magnetic pressure at the cross-point constricts the ablated plasma, which develops instabilities and then pinches to near-zero radius, localized ‘hot spots’, emitting X-rays from a sub-nanosecond and 1 µm scale source characteristic of a hot (~1 keV), dense (10% solid density) plasma. A subsequent gap forms where the hot spot(s) occurred, across which substantial potential accelerates electron beams (e-beams) that generate larger, longer-lasting X-ray bursts composed of harder X-rays.
This project will test the coupling of light emitted from silicon vacancy and nitrogen vacancy defects in diamond into additively manufactured photonic wire bonds toward integration into an "on-chip quantum photonics platform". These defects offer a room-temperature solid state solution for quantum information technologies but suffer from issues such as low activation rate and variable local environments. Photonic wire bonding will allow entanglement of pre-selected solid-state defects alleviating some of these issues and enable simplified integration with other photonic devices. These developments could prove to be key technologies to realize quantum secured networks for national security applications.
The wire segment in question travels in a straight line from position a to b and carries current I in the direction towards b . The magnetic field of this segment alone will not be Maxwellian because the current does not satisfy the continuity equation. However, the field sum of a loop of such wires will be. The integration will be performed along the entire 𝓏 axis (-$\infty$ to $\infty$).
The wire segment in question travels in a straight line from position a to b and carries current I in the direction towards b . The magnetic field of this segment alone will not be Maxwellian because the current does not satisfy the continuity equation. However, the field sum of a loop of such wires will be.
This report summarizes the in situ data collected during three cycles of irradiation (~75 days) of the Wireless Instrumented Removable Beryllium Experiment 2021 (WIRE-21) in the removable beryllium (RB) positions of the High Flux Isotope Reactor (HFIR). The experiment was designed primarily to evaluate the effects of high neutron flux and fluence on the performance of wireless temperature and pressure sensors being developed by Westinghouse Electric Company (WEC). WEC’s sensors could provide critical data regarding the evolution of centerline temperatures and pressurization due to fission gas release during fuel operation in light-water reactors (LWRs) or various advanced reactor applications. In addition to WEC’s wireless sensors, many other sensors were interrogated, including thermocouples, self-powered neutron detectors (SPNDs), distributed fiber optic temperature sensors, and passive neutron flux wires and silicon carbide thermometry.
This Phase 1 technical collaboration project (ORNL/TM-2022/2683) began on August 1st, 2020 and concluded on July 31st, 2022. The collaboration partner Schlumberger is a large business enterprise assisting oil companies to extract oil from land and subsea cost competitively and safely. It is based in Houston, Texas USA. In this work as study of additive deposition of AWS EF100S-G and AWS ERNiCrMo-3 wires via wire-arc process was conducted.
The Fermilab Test Beam is a beam designed for R&D for a variety of experiments taking place at Fermilab, for instance the NOvA experiment. An essential component of the NOvA Test Beam is four wire chambers which measure the transverse position of particles travelling along the beamline. Occasionally, a particle will not produce a hit in one of the four wire chambers resulting in a “3 hit track” instead of the usual “4 hit track”. In our research, we explored the possibility of including these 3 hit tracks into analysis, and how they impact relevant statistics.
MicroBooNE is a Liquid Argon Time Project Chamber (LArTPC) detector whose primary design goal is to understand the “low-energy-excess” anomaly seen by MiniBooNE. MicroBooNE’s currently published results see no excess consistent with the MiniBooNE observation, therefore creating a need for searches in more channels. This note summarizes MicroBooNE’s inclusive single photon selection using Wire-Cell reconstruction and pattern recognition, which will be used to search for a low-energy-excess (LEE) anomaly in the inclusive single photon channel. The selection is similar to the Wire-Cell inclusive electron neutrino selection, but with a different signal definition and some modifications and additions to the pattern recognition tools. A selection with 15.2% efficiency and 18.5% purity is achieved for simulated Standard Model single photon events.
MicroBooNE is a Liquid Argon Time Project Chamber (LArTPC) detector whose primary design goal is to understand the “low-energy-excess” anomaly seen by MiniBooNE. MicroBooNE’s currently published results see no excess consistent with the MiniBooNE observation, therefore creating a need for searches in more channels. This note summarizes MicroBooNE’s inclusive single photon selection using Wire-Cell reconstruction and pattern recognition, which will be used to search for a low-energy-excess (LEE) anomaly in the inclusive single photon channel. The selection is similar to the Wire-Cell inclusive electron neutrino selection, but with a different signal definition and some modifications and additions to the pattern recognition tools. A selection with 15.2% efficiency and 18.5% purity is achieved for simulated Standard Model single photon events.
In this paper, we employ our first principles multipole-based cable braid electromagnetic penetration model to evaluate the transfer inductance of cables exhibiting meandering wires. We concentrate on a cable structure with two wires, and consider the dependence on the transfer inductance as a function of braid angle and amplitude of the meandering. We compare the results from the first principles model to analytical estimations, confirming the accuracy and correctness of our model. In turn, this makes the multipole-based model readily available for the modeling of realistic cable geometries by accounting for the full dependence on the actual cable geometry.
Increasing the fluence of z-pinch x-ray radiation sources above ∼ 10 keV has been a long-standing goal for scientists at Sandia National Laboratories’ Z Machine. Optimizing sources for non-thermal “cold Kα” emission in higher atomic-number materials appears to be a promising path to increase warm x-ray yield. However, this emission is generated by supra-thermal electrons, which are not treated in the magnetohydrodynamic (MHD) codes that are typically used in z-pinch source development. MHD codes do not allow for charge separation or space-charge-generated electric fields, and constrain particle kinematics to Maxwellian distributions. The kinetic codes which do accommodate discrete, non-thermal energy distributions are computationally prohibitive when modeling plasmas near solid density and when modeling/tracking higher ionization states. Thus, modeling non-thermal z-pinch sources requires a new simulation tool. In this report, we present a new hybrid modeling capability that uses the fast features of MHD-type particles to the greatest extent possible, then transitions to the slower but more complete kinetic particle treatment to correctly capture the particle energy spectra that generate non-thermal emission. This capability is founded on the fully-relativistic particle-in-cell code Chicago, which already includes fluid particle treatments. The governing equations and hybrid methodology presented here are applied in simulations of an argon gas-puff and a molybdenum wire-array to provide preliminary code validation. The argon simulation is compared to measured implosion times and yields from Jones et al., Phys. Plasmas 22, 020706 (2015). The simulated x-ray yield is within 25% of measurements and the implosion times agree within a few percent. The molybdenum wire array simulation captures the implosion timing reported in Hansen et al., Phys. Plasmas 21, 031202 (2014), but work is needed to verify the available EOS table. These exemplar simulations represents the type of non-thermal sources that will be developed using the hybrid code capability going forward.
The report covers the RS105 Wire Array Pulser testbed. The setup of the wire array at Reapplication, building 996, is laid out. Setup instructions are provided. Details of the commissioning test are given. Measurement data from the commissioning test shows the field output of the array exceeds 50 kV/m and that tuning the pulser output with a peaking switch can provide a rise time of ~2.3 ns and a pulse width of ~23 ns. The field levels and timeframes shown are within the tolerance conditions of
Exploding wire tests are used to characterize materials undergoing high voltage loading and to validate computational models in a simple configuration. In this report, the materials emphasized are gold, aluminum, copper and nickel wires. Model validation is presented using the nominal model (no uncertainty) in the form of heat maps (per material) that show model bias across scalar quantities and initial voltage. Mesh convergence and uncertainty quantification is also presented.
This report describes the results of bead on pipe welding trials for the purpose of evaluating commercial off the shelf (COTS) 0.047” ER4047 filler material vendors for down selection of the of best candidate filler material for future Gas-metal Arc Welding (GMAW) development efforts. Four candidate COTS ER4047 filler wires were evaluated during this work - Astrolite, Alcotec, Hobart, and Lincoln. The storage condition of each of these filler wires was documented and visual inspection was performed.