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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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DOE OSTI2019

Panel Session 14: US DOE WIPP - Future Plans for the Utilization of a National Asset

This panel focused on the next phase of restoring the Waste Isolation Pilot Plant (WIPP: located in Carlsbad, New Mexico, USA) to full disposal operations. The US DOE Carlsbad Field Office (CBFO) is funded for two Capital Asset Projects that will facilitate the restoration of WIPP to full capability and allow for future repository space planning. The panel will include updates on the capital projects, infrastructure improvements to extend WIPP's operational life, regulatory actions in support of capital projects, and improvements in new processes to implement WAC and DSA enhancements. This panel is filled by CBFO and WIPP contractor leaders to provide the big picture leading to WIPP's future. Presentations proposed include: 1 - 2018 WIPP Year in Review (Bruce Covert, Nuclear Waste Partnership, LLC (USA)); 2 - TRU Waste Shipments and WIPP Operations (Mark Pearcy, Nuclear Waste Partnership, LLC (USA)); 3 - Projects and Activities at WIPP (Ronald Gill, US DOE (USA)); 4 - The Future of WIPP (J.R. Stroble, US DOE (USA), Todd Shrader, US DOE (USA))

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2013

Implementation of a DOD ELAP Conforming Quality System at a FUSRAP Site Field Temporary Radiological Screening Laboratory - 13500

A case study is presented on specific program elements that supported the transition of a temporary field radiological screening lab to an accredited operation capable of meeting client quality objectives for definitive results data. The temporary field lab is located at the Formerly Utilized Sites Remedial Action Program Linde Site in Tonawanda, NY. The site is undergoing remediation under the direction of the United States Army Corps of Engineers - Buffalo District, with Cabrera Services Inc. as the remediation contractor and operator of the on-site lab. Analysis methods employed in the on-site lab include gross counting of alpha and beta particle activity on swipes and air filters and gamma spectroscopy of soils and other solid samples. A discussion of key program elements and lessons learned may help other organizations considering pursuit of accreditation for on-site screening laboratories. (authors)

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2013

A dark-field microscope for background-free detection of resonance fluorescence from single semiconductor quantum dots operating in a set-and-forget mode

Optically active quantum dots, for instance self-assembled InGaAs quantum dots, are potentially excellent single photon sources. The fidelity of the single photons is much improved using resonant rather than non-resonant excitation. With resonant excitation, the challenge is to distinguish between resonance fluorescence and scattered laser light. We have met this challenge by creating a polarization-based dark-field microscope to measure the resonance fluorescence from a single quantum dot at low temperature. We achieve a suppression of the scattered laser exceeding a factor of 10{sup 7} and background-free detection of resonance fluorescence. The same optical setup operates over the entire quantum dot emission range (920–980 nm) and also in high magnetic fields. The major development is the outstanding long-term stability: once the dark-field point has been established, the microscope operates for days without alignment. The mechanical and optical designs of the microscope are presented, as well as exemplary resonance fluorescence spectroscopy results on individual quantum dots to underline the microscope's excellent performance.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

NASA NTRS1990

A teleoperated robotic field geologist

A robotic field geologist, called Teleprospector, is proposed that would be teleoperated from a base on the moon, or possibly from the earth. For field work on Mars, Teleprospector could also be operated from a base in Mars orbit or on the Martian surface. The design incorporates telepresence, so the operator-geologist, though actually located thousands of kilometers away from the telerobot, has the sensation of being inside the body of the robot. The system could be equipped with superhuman sensory capabilities, such as multispectral eyes. This concept combines human intelligence with robotic capabilities, without risk to a human operator, yet still provides the operator with the important sense of personal involvement in the field work.

Taylor, G. Jeffrey↗

NASA NTRS1982

Performance evaluation and calibration of a modular multiband radiometer for remote sensing field research

A multiband radiometer suitable for operation from helicopter, small plane, truck, or tripod platforms was developed. The standard unit is equipped with the seven thematic mapper spectral bands with an added band from 1.5 to 1.30 microns; however, up to eight user specified bands from 0.4 to 15 microns may be installed under clean field conditions. Results of prototype tests of the spectral responsivity of the detectors, the transmittance of the optical filters as a function of wavelength, the fields of view, and the system linearity, temperature stability, noise performance, and dynamic range were evaluated. Minor modifications were made to the instrument and the results of final testing are reported.

Robinson, B. F.↗

DOE OSTI2020

A matrix-free hyperviscosity formulation for high-order ALE hydrodynamics

The numerical approximation of compressible hydrodynamics is at the core of high-energy density (HED) multiphysics simulations as shocks are the driving force in experiments like inertial confinement fusion (ICF). In this work, we describe our extension of the hyperviscosity technique, originally developed for shock treatment in finite difference simulations, for use in arbitrarily high-order finite element methods for Lagrangian hydrodynamics. Hyperviscosity enables shock capturing while preserving the high-order properties of the underlying discretization away from the shock region. Specifically, we compute a high-order term based on a product of the mesh length scale to a high power scaled by a hyper-Laplacian operator applied to a scalar field. We then form the total artificial viscosity by taking a non-linear blend of this term and a traditional artificial viscosity term. We also present a matrix-free formulation for computing the finite element based hyper-Laplacian operator. Such matrix-free methods have superior performance characteristics compared to traditional full matrix assembly approaches and offer advantages for GPU based HPC hardware. We demonstrate the numerical convergence of our method and its application to complex, multi-material ALE simulations on high-order (curved) meshes.

97 MATHEMATICS AND COMPUTING↗

DOE OSTI2016

From Organized High-Throughput Data to Phenomenological Theory using Machine Learning: The Example of Dielectric Breakdown

Understanding the behavior (and failure) of dielectric insulators experiencing extreme electric fields is critical to the operation of present and emerging electrical and electronic devices. Despite its importance, the development of a predictive theory of dielectric breakdown has remained a challenge, owing to the complex multiscale nature of this process. We focus on the intrinsic dielectric breakdown field of insulators—the theoretical limit of breakdown determined purely by the chemistry of the material, i.e., the elements the material is composed of, the atomic-level structure, and the bonding. Starting from a benchmark dataset (generated from laborious first principles computations) of the intrinsic dielectric breakdown field of a variety of model insulators, simple predictive phenomenological models of dielectric breakdown are distilled using advanced statistical or machine learning schemes, revealing key correlations and analytical relationships between the breakdown field and easily accessible material properties. Lastly, the models are shown to be general, and can hence guide the screening and systematic identification of high electric field tolerant materials.

36 MATERIALS SCIENCE↗

NASA NTRS1971

NASA Aircraft Safety and Operating Problems, Volume 1

The proceedings of the Conference on NASA Aircraft Safety and Operating Problems held at Langley Research Center, Hampton, Virginia, on May 4-6, 1971, are reported in this NASA Special Publication. The purpose of this conference was to discuss the results of research of the National Aeronautics and Space Administration in the field of aircraft safety and operating problems. The unclassified program components include the following: Flight Safety Airway and Runway Environment Operational Experience With Subsonic Cruise Aircraft Cockpit Environment Terminal Area Operations Flight Environment Induced Environmental Effects Contributions to this compilation were made by representatives from Ames, Flight, Langley, and Lewis Research Centers, Manned Spacecraft Center, George C. Marshall Space Flight Center, the University of Virginia, the Research Triangle Institute, and the Federal Aviation Administration .

Aircraft Safety Office↗

DOE OSTI2014

Electronic Submersible Pump (ESP) Technology and Limitations with Respect to Geothermal Systems (Fact Sheet)

The current state of geothermal technology has limitations that hinder the expansion of utility scale power. One limitation that has been discussed by the current industry is the limitation of Electric Submersible Pump (ESP) technology. With the exception of a few geothermal fields artificial lift technology is dominated by line shaft pump (LSP) technology. LSP's utilize a pump near or below reservoir depth, which is attached to a power shaft that is attached to a motor above ground. The primary difference between an LSP and an ESP is that an ESP motor is attached directly to the pump which eliminates the power shaft. This configuration requires that the motor is submersed in the geothermal resource. ESP technology is widely used in oil production. However, the operating conditions in an oil field vary significantly from a geothermal system. One of the most notable differences when discussing artificial lift is that geothermal systems operate at significantly higher flow rates and with the potential addition of Enhanced Geothermal Systems (EGS) even greater depths. The depths and flow rates associated with geothermal systems require extreme horsepower ratings. Geothermal systems also operate in a variety of conditions including but not limited to; high temperature, high salinity, high concentrations of total dissolved solids (TDS), and non-condensable gases.

15 GEOTHERMAL ENERGY↗

DOE OSTI2020

The inversion formula and 6j symbol for 3d fermions

In this work we study the 6 j symbol of the 3 d conformal group for fermionic operators. In particular, we study 4-point functions containing two fermions and two scalars and also those with four fermions. By using weight-shifting operators and harmonic analysis for the Euclidean conformal group, we relate these spinning 6 j symbols to the simpler 6 j symbol for four scalar operators. As one application we use these techniques to compute 3 d mean field theory (MFT) OPE coefficients for fermionic operators. We then compute corrections to the MFT spectrum and couplings due to the inversion of a single operator, such as the stress tensor or a low-dimension scalar. These results are valid at finite spin and extend the perturbative large spin analysis to include non-perturbative effects in spin.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2022

Advancing Superconducting Magnet Diagnostics for Future Colliders

Future colliders will operate at increasingly high magnetic fields pushing limits of electromagnetic and mechanical stress on the conductor [1]. Understanding factors affecting superconducting (SC) magnet performance in challenging conditions of high mechanical stress and cryogenic temperatures is only possible with the use of advanced magnet diagnostics. Diagnostics provide a unique observation window into mechanical and electromagnetic processes associated with magnet operation, and give essential feedback to magnet design, simulations and material research activities. Development of novel diagnostic capabilities is therefore an integral part of next-generation magnet development. In this paper, we summarize diagnostics development needs from a prospective of the US Magnet Development Program (MDP), and define main research directions that could shape this field in the near future.

43 PARTICLE ACCELERATORS↗

DOE OSTI2026

Information-theoretic astrophysical uncertainties in the effective theory of dark matter direct detection

The impact of astrophysical uncertainties in direct detection searches can vary significantly across particle dark matter models and detector targets, due to the different velocity and momentum dependencies of the scattering cross section. We address these uncertainties for all operators of the nonrelativistic effective field theory of dark-matter/nucleon interactions, making use of the Kullback-Leibler (KL) information divergence to measure the deviation of the true dark matter velocity distribution from the Maxwell-Boltzmann form. This approach quantifies how astrophysical uncertainties affect each operator in the effective theory, without assuming any specific functional form for the velocity distribution. While for some operators the uncertainties are smaller than 1 order of magnitude for entropically motivated deviations from the Maxwell-Boltzmann form, for other operators, these uncertainties can be as large as three orders of magnitude near threshold. Furthermore, we identify the dependence of the scattering rate for various operators of the effective theory with different velocity-weighted moments of the velocity distribution, functionally analogous to the mean, variance, or skewness. This provides new analytic insight into which features of the velocity distribution are most relevant to detect a given particle dark matter model. Our technique is general and could be applied to a broader class of physics problems where a physical observable depends on the statistical moments of an uncertain theoretical distribution.

Herrera, Gonzalo [MIT, MKI; Harvard U.; Virginia T↗

NASA NTRS2011

Planar Rotary Piezoelectric Motor Using Ultrasonic Horns

A motor involves a simple design that can be embedded into a plate structure by incorporating ultrasonic horn actuators into the plate. The piezoelectric material that is integrated into the horns is pre-stressed with flexures. Piezoelectric actuators are attractive for their ability to generate precision high strokes, torques, and forces while operating under relatively harsh conditions (temperatures at single-digit K to as high as 1,273 K). Electromagnetic motors (EM) typically have high rotational speed and low torque. In order to produce a useful torque, these motors are geared down to reduce the speed and increase the torque. This gearing adds mass and reduces the efficiency of the EM. Piezoelectric motors can be designed with high torques and lower speeds directly without the need for gears. Designs were developed for producing rotary motion based on the Barth concept of an ultrasonic horn driving a rotor. This idea was extended to a linear motor design by having the horns drive a slider. The unique feature of these motors is that they can be designed in a monolithic planar structure. The design is a unidirectional motor, which is driven by eight horn actuators, that rotates in the clockwise direction. There are two sets of flexures. The flexures around the piezoelectric material are pre-stress flexures and they pre-load the piezoelectric disks to maintain their being operated under compression when electric field is applied. The other set of flexures is a mounting flexure that attaches to the horn at the nodal point and can be designed to generate a normal force between the horn tip and the rotor so that to first order it operates independently and compensates for the wear between the horn and the rotor.

Sherrit, Stewart↗

NASA NTRS2017

Wear Trends of the HERMeS Thruster as a Function of Throttle Point

A series of short-duration (200 hour) wear tests were conducted with two Hall Effect Rocket with Magnetic Shielding (HERMeS) technology demonstration units (TDU). Front pole covers, cathode keeper, and discharge channel wear were characterized as a function of discharge voltage, magnetic field strength, and chamber pressure. No discharge channel erosion was observed. Inner pole cover erosion was shown to be a weak function of discharge voltage with most erosion occurring at the lowest value, 300 volts. The TDU-3 keeper electrode eroded with each operating condition, with high magnetic field yielding the greatest erosion rate. The TDU-1 keeper electrode exhibited net deposition suggesting its configuration is more consistent with meeting overall HERMeS service life requirements. Ratios of molybdenum to graphite erosion rates suggests, with high uncertainty, that the sputtering ions are originating downstream of the thruster exit plane, striking the surface with small angles of incidence.

life (durability)↗

DOE OSTI2022

Record High Ramping Rates in HTS Based Superconducting Accelerator Magnet

Here we report results of experimental test of the High Temperature Superconductor (HTS) based fast-cycling prototype accelerator magnet capable to operate up to about 300 T/s field ramping rate with some 0.5 T B-field in the magnet gap. The measured upper limit for the cryogenic cooling power required to support magnet conductor operation at high ramping rates indicates great potential for such type of magnets in rapid cycling synchrotrons for neutrino research or acceleration of very short-lived muons. The test magnet design, construction and supporting cryogenic and power systems are briefly described. The magnet's power test results are discussed in terms of a possible upgrade of this magnet design to 2 T B-field, a maximum feasible with super-ferric magnet.

43 PARTICLE ACCELERATORS↗

NASA NTRS1993

Laser velocimeter measurements of the flow field generated by a forward-swept propfan during flutter

Results are presented from an investigation to measure the flow field generated by a forward-swept propfan operating in flutter at a low forward velocity. For comparison to the flutter condition, flow field data are also presented for a slightly reduced rotational speed just below flutter. The forward-swept propfan was tested as the front rotor of a counterrotating pusher propeller. A laser Doppler velocimeter (LDV) was used to measure the velocity field in planes normal to the model centerline downstream of the rotor and in planes of constant radius within the blade passages at each operating condition. The mean time-averaged flow about the blades did not change drastically as the propfan rotational speed was increased from the stable operating point to the flutter condition. No regions of flow separation could be identified in the data plots of the mean intrablade flow field. The relative flow about the blades remained subsonic during flutter operation. The blades were found to have a higher than expected tip loading at both operating conditions. This is thought to have been caused by the outer blade sections twisting under load to higher than expected effective blade angles. This high tip loading resulted in strong vortices and a very nonuniform flow downstream of the tips of the forward-swept blades. This high tip loading may also have caused the blade flutter.

Podboy, Gary G.↗

DOE OSTI2013

Middlesex FUSRAP Site - A Path to Site-Wide Closure - 13416

The road-map to obtaining closure of the Middlesex Sampling Plant FUSRAP site in Middlesex, New Jersey (NJ) has required a multi-faceted approach, following the CERCLA Process. Since 1998, the US ACE, ECC, and other contractors have completed much of the work required for regulatory acceptance of site closure with unrestricted use. To date, three buildings have been decontaminated, demolished, and disposed of. Two interim storage piles have been removed and disposed of, followed by the additional removal and disposal of over 87,000 tons of radiologically and chemically-impacted subsurface soils by the summer of 2008. The US ACE received a determination from the EPA for the soils Operable Unit, (OU)-1, in September 2010 that the remedial excavations were acceptable, and meet the criteria for unrestricted use as required by the 2004 Record of Decision (ROD) for OU-1. Following the completion of OU-1, the project delivery team performed additional field investigation of the final Operable Unit for Middlesex, OU-2, Groundwater. As of December 2012, the project delivery team has completed a Supplemental Remedial Investigation, which will be followed with a streamlined Feasibility Study, Proposed Plan, and ROD. Several years of historical groundwater data was available from previous investigations and the FUSRAP Environmental Surveillance Program. Historical data indicated sporadic detections of Volatile Organic Compounds (VOCs), primarily trichloroethylene (TCE), carbon tetrachloride (CT), and methyl tert-butyl ether (MTBE), with no apparent trend or pattern indicating extent or source of the VOC impact. In 2008, the project delivery team initiated efforts to re-assess the Conceptual Site Model (CSM) for groundwater. The bedrock was re-evaluated as a leaky multi-unit aquifer, and a plan was developed for additional investigations for adequate bedrock characterization and delineation of groundwater contaminated primarily by CT, TCE, and tetrachloroethene (PCE). The investigation was designed to accumulate multiple lines of evidence to determine the source and to delineate the extent of contamination, as required to complete the CERCLA Process and gain regulatory acceptance. Investigative techniques included in-well vertical flow tracing, borehole geophysics and packer testing of temporary test holes to characterize contamination in the bedrock fractures beneath the site, and to delineate likely source areas. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2017

Improvement of the optical image reconstruction based on multiplexed quantum ghost images

Ghost imaging allows one to obtain information on an object from the spatial correlation function between photons propagating through or reflected from the object and photons of the reference arm. In this case, detection in the object arm is performed over the entire aperture of the beam and, therefore, it does not give information on the object. The reference beam does not interact with the object, but is recorded with a scanning point detector or a CCD array permitting the measurement of the spatial correlation function of photons in two arms. The use of multimode entangled quantum light beams by illuminating the object by one beam and orienting other beams to reference arms makes it possible to obtain simultaneously several ghost images (GIs). Cross correlations of multiplexed GIs (MGIs) are determined by eighth-order field correlation functions. A special algorithm is developed for calculating higher-order correlations of Bose operators. The presence of GI cross correlations is used for improving the quality of the reconstructed object’s image by their processing using the measurement reduction method. An example of the computer simulation of the image reconstruction by MGIs formed in the field of four-frequency entangled quantum states is considered. It is found that in this case the reduced GI has a signal-to-noise ratio several times higher than that of GIs.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗