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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 OSTI2021

Next-Generation Video Ice Particle Sampler Field Campaign Report

The next-generation video ice particle sampler (ngVIPS) was operated on the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) user facility’s tethered balloon system (TBS) during the IFFExO (Ice Fog Field Experiment at Oliktok Point) project in November, 2020. The purpose of the project was to study ice fog microphysics and the environmental conditions during ice fog to enable better predictions during low-visibility conditions. This project was conducted at the site of the third ARM Mobile Facility (AMF3) at Oliktok Point, Alaska. Among a suite of other instruments, the ngVIPS was operated to observe atmospheric ice particles.

47 OTHER INSTRUMENTATION↗
DOE OSTI2019

One- and Two-Qubit Gates: Rabi Technique and Single Unipolar Pulses

Methods for controlling states of interacting superconducting flux qubits using power-efficient devices of fast single-quantum logic (Josephson nonlinearity cavities) are studied. One- and two-qubit quantum logical operations performed within the conventional control technique using Rabi pulses and using picosecond single unipolar magnetic field pulses are comparatively analyzed. It is shown that all main operations can be implemented with an accuracy of better than 97% due to optimization of the shape and parameters of unipolar control pulses (associated with, e.g., propagation of fluxons in transmission lines). The efficiency of the developed technique for programming a two-qubit quantum processor implementing the simplest Deutsch–Jozsa algorithm is demonstrated.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2014

High-frequency thermal-electrical cycles for pyroelectric energy conversion

We report thermal to electrical energy conversion from a 150 nm thick BaTiO{sub 3} film using pyroelectric cycles at 1 kHz. A microfabricated platform enables temperature and electric field control with temporal resolution near 1 μs. The rapid electric field changes as high as 11 × 10{sup 5 }kV/cm-s, and temperature change rates as high as 6 × 10{sup 5 }K/s allow exploration of pyroelectric cycles in a previously unexplored operating regime. We investigated the effect of phase difference between electric field and temperature cycles, and electric field and temperature change rates on the electrical energy generated from thermal-electrical cycles based on the pyroelectric Ericsson cycle. Complete thermodynamic cycles are possible up to the highest cycle rates tested here, and the energy density varies significantly with phase shifts between temperature and electric field waveforms. This work could facilitate the design and operation of pyroelectric cycles at high cycle rates, and aid in the design of new pyroelectric systems.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2011

Spin-to-orbital momentum conversion via electro-optic Pockels effect in crystals

In the present work we have demonstrated a possibility for operation by orbital angular momentum (OAM) of optical beams via the Pockels effect in solid-crystalline materials. Based on the analysis of an optical Fresnel ellipsoid perturbed by a conically shaped electric field, we have shown that the point groups of crystals convenient for the conversion of spin angular momentum (SAM) to OAM should contain a threefold symmetry axis or a sixfold inversion axis. The results of our experimental studies and theoretical simulations of the SAM-to-OAM conversion efficiency carried out for LiNbO{sub 3} crystals agree well with each other.

36 MATERIALS SCIENCE↗
DOE OSTI2014

Towards the Understanding of Induced Seismicity in Enhanced Geothermal Systems

This DOE funded project was a collaborative effort between Array Information Technology (AIT), the University of California at Berkeley (UCB), the Helmholtz Centre Potsdam - German Research Center for Geosciences (GFZ) and the Lawrence Berkeley National Laboratory (LBNL). It was also part of the European research project “GEISER”, an international collaboration with 11 European partners from six countries including universities, research centers and industry, with the goal to address and mitigate the problems associated with induced seismicity in Enhanced Geothermal Systems (EGS). The goal of the current project was to develop a combination of techniques, which evaluate the relationship between enhanced geothermal operations and the induced stress changes and associated earthquakes throughout the reservoir and the surrounding country rock. The project addressed the following questions: how enhanced geothermal activity changes the local and regional stress field; whether these activities can induce medium sized seismicity M > 3; (if so) how these events are correlated to geothermal activity in space and time; what is the largest possible event and strongest ground motion, and hence the potential hazard associated with these activities. The development of appropriate technology to thoroughly investigate and address these questions required a number of datasets to provide the different physical measurements distributed in space and time. Because such a dataset did not yet exist for an EGS system in the United State, we used current and past data from The Geysers geothermal field in northern California, which has been in operation since the 1960s. The research addressed the need to understand the causal mechanisms of induced seismicity, and demonstrated the advantage of imaging the physical properties and temporal changes of the reservoir. The work helped to model the relationship between injection and production and medium sized magnitude events that have jeopardized, and in some cases suspended, the generation of energy from EGS systems worldwide.

15 GEOTHERMAL ENERGY↗
DOE OSTI2024

Absolute magneto-optical measurement of magnetic field on a long pulse high electrical current driven solenoid

We describe a direct absolute magneto-optical approach to measuring the magnetic field driven by long pulse width (>5 ms) and high electrical current (∼kA) in a solenoidal coil. The magnetic field and electrical current are among the most important operating parameters in lightning research and electrical power distribution and are essential to understanding the properties of the radiation output in pulsed energy accelerators as well as other research platforms. However, accurately measuring these magnetic fields and electrical currents using conventional electrical diagnostics is difficult due to the strength of ionizing radiation and electromagnetic interference. Our approach uses a fiber coupled laser beam with a rare earth element material sensing crystal that is highly resistant to electromagnetic interference, allows for absolute measurement, and does not require an external calibration. Here, we focus on device theory, operating parameters, magneto-optical results from an experiment on a high current solenoid, and comparison with a calculation of the magnetic field and reference electrical current flowing downstream of the solenoid.

Owens, Israel [Sandia National Laboratories (SNL-N↗
DOE OSTI2018

Economy and Emissions Impacts from Solazyme Fuel in UPS Delivery Vehicles

To improve understanding of the potential fuel economy and emissions impacts from switching a fleet of vehicles from conventional petroleum diesel to synthetic renewable diesel, the National Renewable Energy Laboratory (NREL) conducted fuel economy and emissions analyses at NREL's Renewable Fuels and Lubricants (ReFUEL) Laboratory. Representative test cycles were developed based on real-world data from six package delivery vehicles and six class 8 day-cab tractors operated by UPS in the Dallas, Texas, area. A three-week in-field data collection period yielded 170 days of real-world vehicle operations data that NREL used to select representative standard drive cycles for testing. Fuel economy and emissions tests at the ReFUEL Laboratory showed that, in general, when switching from conventional diesel to renewable diesel observed changes in tailpipe carbon dioxide (CO2), fuel consumption, and fuel economy are primarily driven by changes in fuel properties such as the hydrogen-to-carbon ratio, density, and lower heating value (LHV). The vehicles tested with the renewable diesel showed a consistent 4.2% reduction in tailpipe CO2 emissions, but a 3.5%-4.8% reduction in fuel economy compared with local pump diesel. This is consistent with the 4.2% lower volumetric LHV of the sourced renewable diesel compared to the pump diesel. The UPS package car tested on renewable diesel also demonstrated a 4.1% oxides of nitrogen (NOx) reduction. NOx emissions from the UPS selective-catalyst-reduction-equipped tractor were an order of magnitude lower than the package car but showed relatively higher variability in results from cycle to cycle.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2019

Coupled Hydrodynamic-Geomechanical Modelling of CO2-WAG Field Development at Farnsworth Unit: A Case Study

Abstract The SWP project is located in a mature waterflood undergoing conversion to CO2-WAG operations at Farnsworth, Texas, USA. Utilized CO2 is anthropogenic, sourced from a fertilizer and an ethanol plant. Major project goals are optimizing the storage/production balance, ensuring storage permanence, and developing best practices for CCUS. This paper provides a review of work performed toward development of a 3D coupled Mechanical Earth Model (MEM) for use in assessment of caprock integrity, fault reactivation potential, and evaluation of stress dependent permeability in reservoir forecasting. Mechanical property estimates computed from geophysical logs at selected wellbores were integrated with 3D seismic elastic inversion products to create a 3D "static" mechanical property model sharing the same geological framework as the existing reservoir simulation model including 3 major faults. Stresses in the MEM were initialized from wellbore stress estimates and reservoir simulation pore pressures. One way and two way coupled simulations were performed using a compositional hydrodynamic flow model and geomechanical solvers. Coupled simulations were performed on history matched primary, secondary (waterflood), and tertiary (CO2 WAG) recovery periods, as well as an optimized WAG prediction period. These simulations suggest that the field has been operating at conditions which are not conducive to either caprock failure or fault reactivation. Two way coupled simulations were performed in which permeability was periodically updated as a function of volumetric strain using the Kozeny-Carmen porosity-permeability relationship. These simulations illustrate the importance of frequent permeability updating when recovery scenarios result in large pressure changes such as in field re-pressurization through waterflood after a long primary depletion recovery period. Conversely, production forecasting results are less sensitive to permeability update frequency when pressure cycles are short and shallow as in WAG cycles. This paper describes initial work on development of a mechanical earth model for use in assessment of geomechanical risks associated with CCUS operations at FWU. The emphasis of this work is on integration of available geomechanical data for creation of the static mechanical property model. Preliminary coupled hydro-mechanical simulations are presented to illustrate some of the key diagnostic output from coupled simulations which will be used in later work for in depth evaluation of specific risk factors such as induced seismicity and caprock integrity.

02 PETROLEUM↗
DOE OSTI2014

The latest developments and outlook for hydrogen liquefaction technology

Liquefied hydrogen is presently mainly used for space applications and the semiconductor industry. While clean energy applications, for e.g. the automotive sector, currently contribute to this demand with a small share only, their demand may see a significant boost in the next years with the need for large scale liquefaction plants exceeding the current plant sizes by far. Hydrogen liquefaction for small scale plants with a maximum capacity of 3 tons per day (tpd) is accomplished with a Brayton refrigeration cycle using helium as refrigerant. This technology is characterized by low investment costs but lower process efficiency and hence higher operating costs. For larger plants, a hydrogen Claude cycle is used, characterized by higher investment but lower operating costs. However, liquefaction plants meeting the potentially high demand in the clean energy sector will need further optimization with regard to energy efficiency and hence operating costs. The present paper gives an overview of the currently applied technologies, including their thermodynamic and technical background. Areas of improvement are identified to derive process concepts for future large scale hydrogen liquefaction plants meeting the needs of clean energy applications with optimized energy efficiency and hence minimized operating costs. Compared to studies in this field, this paper focuses on application of new technology and innovative concepts which are either readily available or will require short qualification procedures. They will hence allow implementation in plants in the close future.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2017

Field Modeling, Symplectic Tracking, and Spin Decoherence for EDM and Muon $g\textrm{-}2$ Lattices

While the first particle accelerators were electrostatic machines, and several electrostatic storage rings were subsequently commissioned and operated, electrostatic storage rings pose a number of challenges. Unlike motion in the magnetic field, where particle energy remains constant, particle energy generally changes in electrostatic elements. Conservation of energy in an electrostatic element is, in practice, only approximate, and it requires careful and accurate design, manufacturing, installation, and operational use. Electrostatic deflectors require relatively high electrostatic fields, tend to introduce nonlinear aberrations of all orders, and are more challenging to manufacture than homogeneous magnetic dipoles. Accordingly, magnetic storage rings are overwhelmingly prevalent. The search for electric dipole moments (EDMs) of fundamental particles is of key importance in the study of C and CP violations and their sources. C and CP violations are part of the Sakharov conditions that explain the matter–antimatter asymmetry in the universe. Determining the source of CP violations would provide valuable empirical insight for beyond-Standard-Model physics. EDMs of fundamental particles have not to this date been experimentally observed. The search for fundamental particle EDMs has narrowed the target search region; however, an EDM signal is yet to be discovered. In 2008, Brookhaven National Laboratory (BNL) had proposed the frozen spin (FS) concept for the search of a deuteron EDM. The FS concept envisions launching deuterons through a storage ring with combined electrostatic and magnetic fields. The electrostatic and magnetic fields are in a proportion that would, without an EDM, freeze the deuteron’s spin along its momentum as the deuteron moves around the lattice. The radial electrostatic field would result in a torque on the spin vector, proportional to a deuteron EDM, rotating the spin vector out of the midplane.

43 PARTICLE ACCELERATORS↗
DOE OSTI2013

Observation of low magnetic field density peaks in helicon plasma

Single density peak has been commonly observed in low magnetic field (<100 G) helicon discharges. In this paper, we report the observations of multiple density peaks in low magnetic field (<100 G) helicon discharges produced in the linear helicon plasma device [Barada et al., Rev. Sci. Instrum. 83, 063501 (2012)]. Experiments are carried out using argon gas with m = +1 right helical antenna operating at 13.56 MHz by varying the magnetic field from 0 G to 100 G. The plasma density varies with varying the magnetic field at constant input power and gas pressure and reaches to its peak value at a magnetic field value of {approx}25 G. Another peak of smaller magnitude in density has been observed near 50 G. Measurement of amplitude and phase of the axial component of the wave using magnetic probes for two magnetic field values corresponding to the observed density peaks indicated the existence of radial modes. Measured parallel wave number together with the estimated perpendicular wave number suggests oblique mode propagation of helicon waves along the resonance cone boundary for these magnetic field values. Further, the observations of larger floating potential fluctuations measured with Langmuir probes at those magnetic field values indicate that near resonance cone boundary; these electrostatic fluctuations take energy from helicon wave and dump power to the plasma causing density peaks.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2017

2016 Annual Site Environmental Report Sandia National Laboratories/New Mexico.

Sandia National Laboratories (SNL) is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s (DOE’s), National Nuclear Security Administration (NNSA). The DOE/NNSA Sandia Field Office administers the contract and oversees contractor operations at SNL, New Mexico. This Annual Site Environmental Report (ASER) summarizes data and the compliance status of sustainability, environmental protection, and monitoring programs at SNL/NM during calendar year 2016. Major environmental programs include air quality, water quality, groundwater protection, terrestrial and ecological surveillance, waste management, pollution prevention, environmental restoration, oil and chemical spill prevention, and implementation of the National Environmental Policy Act. This ASER is prepared in accordance with and required by DOE O 231.1B, Admin Change 1, Environment, Safety, and Health Reporting.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2017

Reducing Reaction Temperature, Steam Requirements, and Coke Formation During Methane Steam Reforming Using Electric Fields: A Microkinetic Modeling and Experimental Study

In this study, we approach several common problems with the Ni-catalyzed methane steam reformation reaction (MSR) using a two-pronged approach combining density functional theory (DFT) calculations with experimental work. Specifically, we look at the deactivation of a Ni catalyst due to coke formation, its high operating temperature requirements, and the high steam-to-methane (H 2 O/CH 4 ) ratio needed for proper MSR operation. A DFT-based microkinetic model was developed in the presence and absence of electric fields and the results were compared with experimental results. The microkinetic model shows that under various electric fields, the most favorable MSR mechanism changed slightly. It also shows that the presence of a positive electric field decreases the surface coverage of carbon, increases the water coverage, accelerates the rate-limiting step of the C-H bond cleavage in methane, and increases the desorption rates of the syngas product (CO + H 2 ) during MSR. Consequently, for a given methane conversion, a positive electric field allows for significantly lower H 2 O/CH 4 ratio and operating temperatures as compared to systems without an electric field. These findings correspond well with experimental tests under a variety of operating conditions. In addition, improvement in the catalytic activity due to the presence of a positive electric field remained significant even at industrially relevant applied pressures improving the hydrogen yield greatly. Overall, we find that an applied electric field can play a significant role in improving the catalytic activity of heterogeneous reactions. Here, this information can guide the design of heterogeneous reactions in the presence of an electric field. By utilizing the electric field generated by various renewable energy sources, electric field assisted heterogeneous reactions can open up a paradigm in future energy research.

03 NATURAL GAS↗
DOE OSTI2018

FUSRAP Case Study - Benefits and Lessons Learned from Implementation of a Modern Data Solution at Maywood - 18399

This paper focuses on data production and management practices dating back to 1999 that continue to evolve to support the project today. In 2000, the FUSRAP Maywood Project began using a software environmental data management system and laboratory information management system, developed by a single database administrator (DA) and authored in Microsoft Access{sup TM} (MS Access). The original databases included basic functionality including sample number assignment and label generation, tracking of LIMS gamma spec QC and assignment of basic qualifiers and basic database queries. The DA continued over the next fifteen years to refine the EDMS/LIMS by integrating project-specific data evaluation guidance document processes and Quality Assurance/Quality Control (QA/QC) charting and excursion warning tools. With the retirement of the original DA, the U.S. Army Corps of Engineers (USACE)-Cabrera Team procured and implemented a commercial-leaning solution using modern database tools and an established EDMS vendor. For the database transition process, the project team established and configured the new EDMS/LIMS with basic architecture and accessibility; evaluated existing workflows; established/revised LIMS and EDMS-related documentation (manuals and procedures); and conducted dry runs and validation testing. The overall team coordinated closely to facilitate a seamless transition from initial assessment and authoring, to data migration, and finally to resumption of normal ongoing operations. Key features of the new EDMS Subcontractor's software included lookup tables, an import wizard, data checking options and unique indexes. Since the database systems became operational, the technical staff gathered useful feedback from end users (e.g., lab staff, field engineers, task managers, and the third-party data validator) to refine the EDMS/LIMS operation. This feedback triggered improvements in the performance of onsite laboratory qualification forms, promoted consistency in sample ID numbers between the database sample planning screens and field chain-of-custodies, corrected bugs in the LIMS Duplicate Evaluation Report, eliminated data import issues such as blank, inconsistent or missing data from key fields. One of the advantages of the commercial database solution was that it allowed the project to cut cost over time due to the lower cost of database maintenance provided by the commercial database vendor versus the cost of an on-staff DA. Cost savings are estimated at $40,000 per year. There were also indirect cost savings resulting from implementation of the new database since it allowed better integration of the LIMS and EDMS. While there will always be challenges associated with long term records/data management for any old remediation site, the Maywood Team's approach to an upgraded EDMS/LIMS implementation serves as one element of the overall effort to enhance the integrity and reproducibility of critical data that supports the remediation program while at the same time, more effectively using available resources. These lessons-learned will enhance implementation of cost-effective solutions for similar environmental remediation sites. (authors)

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2019

UNDERSTANDING AND MITIGATION OF FIELD EMISSION IN CEBAF SRF LINACS

We present our current understanding of field emission (FE) in two 1.1 GeV continuous wave (CW) superconducting radio frequency (SRF) linacs at CEBAF and its mitigation for improved CEBAF energy reach and operation reliability. We focus on the root causes of FE in operational SRF cavities, including recently installed cavities for CEBAF 12 GeV energy upgrade. We evaluate the effect of initial mitigations implemented since 2016, aimed at reducing generation and transportation of new field emitting particulates. Effects of cavity thermal cycling aimed at abating activation of settled field emitting particulates will be evaluated as well. Remaining issues toward predictable control of field emission in operational SRF cavities will be discussed.

Geng, R.L.↗
DOE OSTI2023

MACHINE LEARNING-ENABLED PREDICTION OF TRANSIENT INJECTION MAP IN AUTOMOTIVE INJECTORS WITH UNCERTAINTY QUANTIFICATION

Accurate prediction of injection profiles is a critical aspect of linking injector operation with engine performance and emissions. However, highly resolved injector simulations can take one to two weeks of wall-clock time, which is incompatible with engine design cycles with desired turnaround times of less than a day. Hence, it is important to reduce the time-to-solution of the internal flow simulations by several orders of magnitude to make it compatible with engine simulations. This work demonstrates a data-driven approach for tackling the computational overhead of injector simulations, whereby the transient injection profiles are emulated for a side-oriented, single-hole diesel injector using a Bayesian machine-learning framework. First, an interpretable Bayesian learning strategy was employed to understand the effect of design parameters on the total void fraction field. Then, autoencoders are utilized for efficient dimensionality reduction of the flowfields. Gaussian process models are finally used to predict the spatiotemporal void fraction field at the injector exit for unknown operating conditions. The Gaussian process models produce principled uncertainty estimates associated with the emulated flowfields, which provide the engine designer with valuable information of where the data-driven predictions can be trusted in the design space. The Bayesian flowfield predictions are compared with the corresponding predictions from a deep neural network, which has been transfer-learned from static needle simulations from a previous work by the authors. The emulation framework can predict the void fraction field at the exit of the orifice within a few seconds, thus achieving a speed-up factor of up to 38 x 10(6) over the traditional simulation-based approach of generating transient injection maps.

machine learning↗
DOE OSTI2017

DIELECTRICALLY-LOADED WAVEGUIDE AS A MICROWAVE UNDULATOR FOR HIGH BRILLANCE X-RAYS AT 45 – 90 KeV

The HEM12 mode in a cylindrical, dielectrically-loaded waveguide provides E and H fields on the central axis that are significantly higher than the fields on the conducting walls. This structure, operating near the cutoff frequency of the HEM12 mode, spans a frequency range where the wavelength and phase velocity vary significantly. This property can be exploited to generate undulator action with short periods for the generation of high brightness xrays. The frequency range of interest would be from 18 to 34.5-GHz. The goal would be to generate x-rays on the fundamental mode over a range of 45 to 90-keV.The tunability would be achieved by changing the source frequency while maintaining a constant on-axis equivalent undulator field strength of 0.5-T.

Kustom, R. L.↗
DOE OSTI2014

Poly-Gaussian model of randomly rough surface in rarefied gas flow

Surface roughness is simulated by the model of non-Gaussian random process. Our results for the scattering of rarefied gas atoms from a rough surface using modified approach to the DSMC calculation of rarefied gas flow near a rough surface are developed and generalized applying the poly-Gaussian model representing probability density as the mixture of Gaussian densities. The transformation of the scattering function due to the roughness is characterized by the roughness operator. Simulating rough surface of the walls by the poly-Gaussian random field expressed as integrated Wiener process, we derive a representation of the roughness operator that can be applied in numerical DSMC methods as well as in analytical investigations.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗