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DOE OSTI2018

SRNL 2017 LDRD Annual Report

Fiscal Year (FY) 2017 marked the twelfth year of Savannah River National Laboratory’s (SRNL’s) Laboratory Directed Research and Development (LDRD) program and the largest year to date. When the program began in FY06, just two years after SRNL becoming the DOE’s 17th national lab, it began with a modest authorized collection rate of just under 1.5%. It grew from there each year, reaching 4% in FY11. FY17 marked the first increase in the authorized collection rate since FY11, increasing from 4% to 5%. This increase highlights the value placed on this important program, which provides the discretionary funding needed to develop ideas for future programmatic growth in our key business areas of environmental stewardship, national security, nuclear materials management, and secure energy manufacturing, as well as develop and maintain our core competencies. The LDRD program leverages the unique capabilities of SRNL to yield foundational scientific research and development (R&D) essential to our core business areas, while aligning optimally and continuously with SRNL’s Strategic Plan and providing long-term benefits to DOE and the National Nuclear Security Administration (NNSA), other customers, and stakeholders. As can be seen in the “By the Numbers” summary, this program also plays an important role in sustaining staff excellence with high participation by students, post-docs, and early-career staff. Over 75% of the projects in FY17 included contributions from early-career or post-doctoral staff.

99 GENERAL AND MISCELLANEOUS↗

DOE OSTI2019

2018 LDRD annual report

Fiscal Year (FY) 2018 marked the thirteenth year of Savannah River National Laboratory’s (SRNL’s) Laboratory Directed Research and Development (LDRD) program and the largest year to date. When the program began in FY06, just two years after SRNL becoming the DOE’s 17th national lab, it began with a modest authorized collection rate of just under 1.5%. It grew from there each year, reaching 5% in FY17. The authorized collection rate was maintained at 5% on FY18. The increase in collection rates experienced during the last years evidences the value placed on this important program, which provides the discretionary funding needed to develop ideas for future programmatic growth in our key business areas of environmental stewardship, national security, nuclear materials management, and secure energy manufacturing, as well as develop and maintain our core competencies. The LDRD program leverages the unique capabilities of SRNL to yield foundational scientific research and development (R&D) essential to our core business areas, while aligning optimally and continuously with SRNL’s Strategic Plan and providing long-term benefits to DOE and the National Nuclear Security Administration (NNSA), other customers, and stakeholders. As can be seen in the “By the Numbers” summary, this program also plays an important role in sustaining staff excellence with high participation by students, post-docs, and early-career staff. Over 85% of the projects in FY18 included contributions from early-career or post-doctoral staff.

99 GENERAL AND MISCELLANEOUS↗

DOE OSTI2020

Multi-Functional Distributed Fiber Sensors for Pipeline Monitoring and Methane Detections. Final Report

As an abundant and cheap fossil energy source, natural gas has become a significant energy supply to support the United States’ economy. However, the large-scale extraction and utilization of natural gas also impose significant challenges on methane leakage. This problem is exacerbated by aging gas utility delivery systems, including interstate high-pressure pipelines, storage, and transmission facilities. This project aims to develop a cost-effective fiber optical sensing method that can perform multi-parameter real-time measurements of natural gas pipelines across long interrogation distances up to 100 km with 1-meter spatial resolution. This sensing tool can evaluate overall pipeline efficiency and reduce methane emissions for mid-stream methane infrastructures. To accomplish this objective, research and development efforts funded by this project have resulted in the following accomplishments: This project successfully has developed new functional sensory polymer materials using Metal-Organic Frameworks (MOFs) that can be coated on optical fiber through the reel-to-reel coating process. Functional polymer-coated optical fibers can perform sensitive methane detection through evanescence wave interaction and strain-based measurements to achieve 1% detection sensitivities. The new sensors fibers support both distributed measurements and multiplexed fiber sensors array for multi-point measurements. This project developed and optimized a new multi-core optical fiber that supports simultaneous and distributed measurements of strain and temperatures with 1-meter spatial resolutions across up to 100-km interrogation distance. This new fiber, combined with sensory polymercoated fiber, could perform both distributed temperature and methane detections. This project developed a new artificial intelligence big data algorithm approach that can effectively analyze high-resolution data harnessed by distributed fiber sensors to protect natural gas pipelines against external threats and detect internal defects induced by corrosion. Working with our industry partner, this project developed new optical fibers that support fiber sensor fabrications through polymer coating after the fibers are drawn. These new fibers eliminate the need for direct sensor fabrication when the fiber is fabricated on a fiber draw tower, which drastically expands fiber sensors' applicability. This research project has significantly advanced the distributed fiber sensing technology. It will dramatically increase the applicability and adaptability of distributed fiber sensors for a wide array of applications in energy, sustainability, and environmental science, including structural health monitoring of natural gas pipelines, oil infrastructures, hydrogen facilities, and environmental monitoring of carbon storage sites, water supply systems, and others.

03 NATURAL GAS↗

DOE OSTI2021

FY2020 LDRD Annual Report

The Laboratory Directed Research and Development (LDRD) program funds scientific efforts to build upon the unique knowledge base of Savannah River National Laboratory (SRNL). The program yields foundational scientific research and development (R&D) essential to SRNL’s core business areas, while aligning optimally and continuously with SRNL’s Strategic Plan and providing long-term benefits to DOE and the National Nuclear Security Administration (NNSA), other customers, and stakeholders. While fiscal year (FY) 2020 presented unprecedented challenges due to the COVID-19 global pandemic, the SRNL research team continued to advance science and further technology through the support of the LDRD program.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2022

Savannah River National Laboratory (FY2021 LDRD Annual Report)

Research efforts to build upon the unique knowledge base of the Savannah River National Laboratory (SRNL) are funded through the Laboratory Directed Research and Development (LDRD) Program. The program yields foundational scientific research and development (R&D) essential to SRNL’s core business areas, while aligning optimally and continuously with SRNL’s Strategic Plan to provide long-term benefits to the Department of Energy (DOE), the National Nuclear Security Administration (NNSA), and other customers and stakeholders.

99 GENERAL AND MISCELLANEOUS↗

NASA NTRS1967

CINDA - Chrysler Improved Numerical Differencing Analyzer computer program

Dimensionless multioption systems compiler computer program constructs and analyzes a mathematical model of any arbitrary one, two, or three dimensional lumped parameter representation of a physical system. It automatically optimizes the utilization of computer core space and is more general and versatile than BETA.

Gaski, J. D.↗

NASA NTRS1972

Space Storable Propellant Performance Gas/Liquid Like-Doublet Injector Characterization

A 30-month applied research program was conducted, encompassing an analytical, design, and experimental effort to relate injector design parameters to simultaneous attainment of high performance and component (injector/thrust chamber) compatibility for gas/liquid space-storable propellants. The gas/liquid propellant combination selected for study was FLOX (82.6% F2)/ambient temperature gaseous methane. The injector pattern characterized was the like-(self)-impinging doublet. Program effort was apportioned into four basic technical tasks: injector and thrust chamber design, injector and thrust chamber fabrication, performance evaluation testing, and data evaluation and reporting. Analytical parametric combustion analyses and cold flow distribution and atomization experiments were conducted with injector segment models to support design of injector/thrust chamber combinations for hot fire evaluation. Hot fire tests were conducted to: (1) optimize performance of the injector core elements, and (2) provide design criteria for the outer zone elements so that injector/thrust chamber compatibility could be achieved with only minimal performance losses.

Falk, A. Y.↗

NASA NTRS1984

Specifications for a Federal Information Processing Standard Data Dictionary System

The development of a software specification that Federal agencies may use in evaluating and selecting data dictionary systems (DDS) is discussed. To supply the flexibility needed by widely different applications and environments in the Federal Government, the Federal Information Processing Standard (FIPS) specifies a core DDS together with an optimal set of modules. The focus and status of the development project are described. Functional specifications for the FIPS DDS are examined for the dictionary, the dictionary schema, and the dictionary processing system. The DDS user interfaces and DDS software interfaces are discussed as well as dictionary administration.

Goldfine, A.↗

NASA NTRS1986

Feasibility analysis of reciprocating magnetic heat pumps

The conceptual design selected for detailed system analysis and optimization is the reciprocating gadolinium core in a regenerative fluid column within the bore of a superconducting magnet. The thermodynamic properties of gadolinium are given. A computerized literature search for relevant papers was conducted and is being analyzed. Contact was made with suppliers of superconducting magnets and accessories, magnetic materials, and various types of hardware. A description of the model for the thermal analysis of the core and regenerator fluids is included.

Larson, A. V.↗

NASA NTRS2004

Modeling of Electro Optic Polymer Electrical Characteristics in a 3 layer Optical Waveguide Modulator

The electrical characteristics of electro optic polymer waveguide modulators are often described by the bulk reactance of the individual layers. However, the resistance and capacitance between the layers can significantly alter the electrical performance of a waveguide modulator. These interface characteristics are related to the boundary charge density and are strongly affected by the adhesion of the layers in the waveguide stack. An electrical reactance model has been derived to investigate this phenomenon at low frequencies. The model shows the waveguide stack frequency response has no limiting effects below the microwave range and that a true DC response requires a stable voltage for over 1000 hours. Thus, reactance of the layers is the key characteristic of optimizing the voltage across the core layer, even at very low frequencies (> 10(exp -6) Hz). The results of the model are compared with experimental data for two polymer systems and show quite good correlation.

Watson, Michael D.↗

DOE OSTI2017

Particle In Cell Scalable Application Resource (PICSAR) v2

PICSAR, for Particle-In-Cell Scalable Application Resource, is a high-performance Particle-in-Cell library developed in Fortran 90 and Python. This library was first developed to be coupled with WARP and provide efficient subroutines optimized for Many-Integrated Core (MIC) architectures such as the forthcoming system Cori Phase II that will be equipped with Intel Xeon Phi KNL processors. It is a compact self-contained proxy that adequately portrays the computational loads and dataflow of the more complex WARP code but can also be used by other PIC codes. PICSAR also contains a Fortran stand-alone Particle-In-Cell "mini-app" that includes the key functionalities of a PIC code. This stand-alone code is used for testing implementation performances and to do some benchmarks.

VINCENTI, HENRI↗

DOE OSTI2020

NREL's Capabilities in Organism Development and Fermentation Sciences Research and Development (R&D)

NREL is developing robust microbial strains and scalable fermentation technologies for converting biomass sugars to fuels and biochemicals, and one-carbon (C1) gaseous substrates (e.g., CO2, CO, CH4) to high-value products. Core capabilities include: (1) Fermentation optimization of aerobic, microaerophilic, and anaerobic cultivation processes of gas and traditional liquid fermentation R&D; (2) Gas mass transfer R&D and CFD modeling for improved reactor design and gas mixing (3) Metabolic engineering in CRISPR editing tools to improve titer, rates, and yields; (4) Probing and optimizing carbon, redox, and energy flux using transcriptomics and fluxomic techniques; and (5) Consolidated bioprocessing (CBP) using cellulose and hemicellulose directly to minimize pretreatment.

BASIC BIOLOGICAL SCIENCES,BIOMASS FUELS,SYNTHETIC ↗

DOE OSTI2023

Method and apparatus for constructing informative outcomes to guide multi-policy decision making

In Multi-Policy Decision-Making (MPDM), many computationally-expensive forward simulations are performed in order to predict the performance of a set of candidate policies. In risk-aware formulations of MPDM, only the worst outcomes affect the decision making process, and efficiently finding these influential outcomes becomes the core challenge. Recently, stochastic gradient optimization algorithms, using a heuristic function, were shown to be significantly superior to random sampling. In this disclosure, it was shown that accurate gradients can be computed-even through a complex forward simulation—using approaches similar to those in dep networks. The proposed approach finds influential outcomes more reliably, and is faster than earlier methods, allowing one to evaluate more policies while simultaneously eliminating the need to design an easily-differentiable heuristic function.

Olson, Edwin↗

DOE OSTI2012

Conceptual design and optimization for a low-power ADS with a 70 MeV, 0.75 mA proton beam

In the framework of research on Generation IV reactors, it is very important to have infrastructures specifically dedicated to the study of fundamental kinetic and dynamic parameters of future fast-neutron reactors, a capability not provided by many presently available or planned zero-power prototypes. We propose the conceptual design of an ADS with high safety standards, in order to be used as a training facility, but also a good flexibility so as to allow for a wide range of static an dynamic measurements and experiments. A high safety standard is guaranteed by limiting the system power to less than 500 kW and the neutron multiplication coefficient k{sub eff} to less than 0.95 (a limiting value for waste storage areas), by using pure Uranium fuel (no Plutonium) and by using solid Lead as a diffuser. Lead has been chosen by considering this prototype to be a useful step towards the design of future Lead Fast Reactors, as well as because it allows a harder neutron spectrum, which facilitates tests on actinides fission, and provides meaningful data on the physics of this metal, which is one of the proposed coolants for future Generation IV reactors. The system is intrinsically subcritical and it needs an external neutron source to be sustained. Specific goal of the present work is to optimize design features of the core in such a way to meet previously declared requirements with the use of a commercially available accelerator in order to reduce costs and increase reliability. The conceptual design requires, in the 'full configuration', 60 active elements, each made by a solid Lead matrix of dimensions 92 x 92 x 1200 mm{sup 3}, each containing 81 Uranium oxide fuel rods, enriched 20% w/o in {sup 235}U. Protons, coming from a continuous cyclotron of 70 MeV in energy and 0.75 mA in beam current, are converted into neutrons by a Beryllium target. Cooling is provided by Helium gas, transparent to neutron and not subject to activation. (authors)

07 ISOTOPE AND RADIATION SOURCES↗

DOE OSTI2017

Core Reactivity Control for a Soluble Boron Free Small Modular Reactor

Soluble boron has been used in pressurized water reactors (PWRs) to control the core excess reactivity in a uniform and stable way without distorting power distributions. It also enables current commercial PWRs to have high core power density. Despite its outstanding advantages, the soluble boron raises several significant concerns such as soluble boron-induced corrosion of structures, a large amount of liquid waste generation, and a possibility of positive moderator temperature coefficient (MTC) at high boron concentration. These concerns become more serious as the concentration of boron becomes higher. Therefore boron in the primary coolant has been a hindrance to the power uprate and cycle extension operation of PWRs. Currently a government-supported research project is underway to develop technologies for the soluble-boron-free (SBF) operation of a PWR-type small modular reactor (SMR). This paper presents preliminary results of the SBF SMR core reactivity control methods including optimization of burnable absorbers (BA) and control rod design, and development of secondary shutdown system (SSS)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2023

3D full core BEAVRS using OpenMOC with transport equivalence

Using an optimized implementation of the three-dimension method of characteristics for neutron transport, as well as a novel equivalence method for transport calculations de- signed to recover self-shielding errors from neglecting the angular dependence of reso- nant group absorption, a 3D full core light water reactor hybrid stochastic-deterministic eigenvalue calculation was achieved. This paper presents the optimizations developed and compares the transport solutions obtained. It realizes a runtime near 6,000 CPU hours for the statepoint, an improvement of an order of magnitude on previous works, with less than 1% error on pin fission/U-238 capture ratios and a few dozen pcms on the eigenvalue.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

DOE OSTI2024

Three-Dimensional Full-Core BEAVRS Using OpenMOC with Transport Equivalence

Using an optimized implementation of the three-dimensional (3D) method of characteristics for neutron transport, along with a novel equivalence method for transport calculations that was designed to correct self-shielding errors from neglecting the angular dependence of resonant group absorption, a 3D full-core light water reactor hybrid stochastic-deterministic eigenvalue calculation was achieved. This paper presents the optimizations developed and compares the transport solutions obtained. For the statepoint, run times near 10 000 CPU hours are achieved—improving on previous works by an order of magnitude—with near 1% error on pin fission to 238 U capture ratios and a few dozen pcms on the eigenvalue.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

DOE OSTI2014

High Energy Electromagnetic Particle Transportation on the GPU

We present massively parallel high energy electromagnetic particle transportation through a finely segmented detector on a Graphics Processing Unit (GPU). Simulating events of energetic particle decay in a general-purpose high energy physics (HEP) detector requires intensive computing resources, due to the complexity of the geometry as well as physics processes applied to particles copiously produced by primary collisions and secondary interactions. The recent advent of hardware architectures of many-core or accelerated processors provides the variety of concurrent programming models applicable not only for the high performance parallel computing, but also for the conventional computing intensive application such as the HEP detector simulation. The components of our prototype are a transportation process under a non-uniform magnetic field, geometry navigation with a set of solid shapes and materials, electromagnetic physics processes for electrons and photons, and an interface to a framework that dispatches bundles of tracks in a highly vectorized manner optimizing for spatial locality and throughput. Core algorithms and methods are excerpted from the Geant4 toolkit, and are modified and optimized for the GPU application. Program kernels written in C/C++ are designed to be compatible with CUDA and OpenCL and with the aim to be generic enough for easy porting to future programming models and hardware architectures. To improve throughput by overlapping data transfers with kernel execution, multiple CUDA streams are used. Issues with floating point accuracy, random numbers generation, data structure, kernel divergences and register spills are also considered. Performance evaluation for the relative speedup compared to the corresponding sequential execution on CPU is presented as well.

Canal, P.↗