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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 901 records · Page 50
All sourcesNASA NTRSDOE OSTI
DOE OSTI2014

Developing A Laser Shockwave Model For Characterizing Diffusion Bonded Interfaces

12. Other advances in QNDE and related topics: Preferred Session Laser-ultrasonics Developing A Laser Shockwave Model For Characterizing Diffusion Bonded Interfaces 41st Annual Review of Progress in Quantitative Nondestructive Evaluation Conference QNDE Conference July 20-25, 2014 Boise Centre 850 West Front Street Boise, Idaho 83702 James A. Smith, Jeffrey M. Lacy, Barry H. Rabin, Idaho National Laboratory, Idaho Falls, ID ABSTRACT: The US National Nuclear Security Agency has a Global Threat Reduction Initiative (GTRI) which is assigned with reducing the worldwide use of high-enriched uranium (HEU). A salient component of that initiative is the conversion of research reactors from HEU to low enriched uranium (LEU) fuels. An innovative fuel is being developed to replace HEU. The new LEU fuel is based on a monolithic fuel made from a U-Mo alloy foil encapsulated in Al-6061 cladding. In order to complete the fuel qualification process, the laser shock technique is being developed to characterize the clad-clad and fuel-clad interface strengths in fresh and irradiated fuel plates. The Laser Shockwave Technique (LST) is being investigated to characterize interface strength in fuel plates. LST is a non-contact method that uses lasers for the generation and detection of large amplitude acoustic waves to characterize interfaces in nuclear fuel plates. However the deposition of laser energy into the containment layer on specimen’s surface is intractably complex. The shock wave energy is inferred from the velocity on the backside and the depth of the impression left on the surface from the high pressure plasma pulse created by the shock laser. To help quantify the stresses and strengths at the interface, a finite element model is being developed and validated by comparing numerical and experimental results for back face velocities and front face depressions with experimental results. This paper will report on initial efforts to develop a finite element model for laser shock.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2016

Development of Zirconium-Silicide Coatings for Improved Performance Zirconium-Alloy Fuel Cladding

There is considerable interest in the development of coatings for zirconium-alloy fuel cladding used in light water reactors (LWR) to improve their oxidation resistance during high temperature accident conditions and to enhance performance under normal operating conditions. These coatings should also enhance the heat transfer characteristics of the cladding surface so that heat from the fuel rod is efficiently transferred into the water coolant. One potential candidate coating material is zirconium-silicide. Transition metal silicides have been generally shown to have outstanding oxidation resistance. Zirconium-silicide is particularly attractive because Zr is strongly oxophilic, so that the Zr-silicide layer is expected to bond more strongly to the inner, native ZrO{sub 2} layer. The relative proximity of the free energy of formation of oxides of Zr and Si can lead to alternating multilayered oxide structures with radiation damage resistance. Additionally, oxidation of zirconium silicide can produce excellent corrosion resistant glassy zircon (ZrSiO{sub 4}) and silica (SiO{sub 2}), possessing self-healing qualities. This paper reports results of our results of high temperature oxidation tests of bulk zirconium-silicide and coatings of zirconium-silicide deposited on zirconium-alloy test flats and cladding tube configurations using plasma vapor deposition (PVD) process. We also report our initial results on the experimental facility for studying boiling characteristics of coated cladding tubes in prototypic pressurized water conditions. (authors)

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2020

BISON Development and Validation for Priority LWR-ATF concepts

Over the years, the Nuclear Energy Advanced Modeling and Simulation (NEAMS) (2015-2018, 2020) and Consortium for Advanced Simulation of Light Water Reactors (CASL) (2019) programs have provided support for development of Accident Tolerant Fuel (ATF) material models in the BISON fuel performance code. Since the beginning, the goal has been to utilize a multiscale modeling approach to gain a physical understanding of the fuel concepts of interest and to develop mechanistic models in the absence of a large amount of experimental data. This work builds upon that of previous years. In particular we present newly updated fission gas release models for both gas behavior in Cr 2 O 3 -doped UO 2 and U 3 Si 2 fuels, and a new creep model for U 3 Si 2 . The validation exercises completed last year are revisited with the latest models and the results updated. A brief summary of recent modeling activities for FeCrAl cladding is also provided.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2024

Use of a Lignin-Based Admixture for Tailoring the Rheological Properties of Mortars for 3D Printing: Preprint

Efforts toward decarbonizing construction materials and industrial processes related to cement and concrete can be aided via multifaceted approaches that target alternative admixtures as well as precision control of fabrication. Chemical admixtures for water reduction have played a crucial role in the development of advanced concrete mixtures. Newer biomass processing techniques developed for aviation fuel production from corn stover biomass produce a more reactive lignin byproduct that is suitable for chemical modifications to mimic the properties of polycarboxylate ether admixtures with a smaller carbon footprint. The present study examines the use of lignin-based water-reducing admixture in cement pastes and mortar mixtures for 3D printing. The experimental program explores the use of different dosages of lignin-based admixture to produce 3D-printed samples with appropriate extrudability and buildability. The rheological characterization was performed to determine the flow curve of various mixtures. Finally, the heat of hydration of cement pastes was monitored via isothermal calorimetry to assess the impact of lignin-based admixtures on the hydration process of cement. The results of this study indicate that the use of biomass by-products, such as lignin-based admixtures have great potential to effectively control the fresh-state properties of cement-based materials.

bio-based admixtures↗
DOE OSTI2016

Compatibility Assessment of Fuel System Elastomers with Bio-oil and Diesel Fuel

Bio-oil derived via fast pyrolysis is being developed as a renewable fuel option for petroleum distillates. The compatibility of neat bio-oil with six elastomer types was evaluated against the elastomer performance in neat diesel fuel, which served as the baseline. The elastomers included two fluorocarbons, six acrylonitrile butadiene rubbers (NBRs), and one type each of fluorosilicone, silicone, styrene butadiene rubber (SBR), polyurethane, and neoprene. Specimens of each material were exposed to the liquid and gaseous phases of the test fuels for 4 weeks at 60 degrees C, and properties in the wetted and dried states were measured. Exposure to bio-oil produced significant volume expansion in the fluorocarbons, NBRs, and fluorosilicone; however, excessive swelling (over 80%) was only observed for the two fluorocarbons and two NBR grades. The polyurethane specimens were completely degraded by the bio-oil. In contrast, both silicone and SBR exhibited lower swelling levels in bio-oil compared to neat diesel fuel. The implication is that, while polyurethane and fluorocarbon may not be acceptable seal materials for bio-oils, silicone may offer a lower cost alternative.

09 BIOMASS FUELS↗
DOE OSTI2014

High-Activity Dealloyed Catalysts

Reduction of costly Pt usage in proton exchange membrane fuel cell electrodes is one of the major challenges towards development and commercialization of fuel cell vehicles. Although few have met the initial-kinetic activity requirements in a realistic fuel cell device, no catalyst material has ever met the demanding fuel cell durability targets set by DOE. In this project, a team of 4 universities and 2 companies came together to investigate a concept that appeared promising in preliminary non-fuel cell tests then to further develop the catalyst to a mature level ready for vehicle implementation. The team consists of academia with technical leadership in their respective areas, a catalyst supplier, and a fuel cell system integrator.The tightly collaborative project enabled development of a highly active and durable catalyst with performance that significantly exceeds that of previous catalysts and meets the DOE targets for the first time (Figure 1A). The catalyst was then further evaluated in full-active-area stack in a realistic vehicle operating condition (Figure 1B). This is the first public demonstration that one can realize the performance benefit and Pt cost reduction over a conventional pure Pt catalyst in a long-term realistic PEMFC system. Furthermore, systematic analyses of a range of catalysts with different performance after fuel cell testing allowed for correlation between catalyst microstructure and its electrocatalytic activity and durability. This will in turn aid future catalyst development.

30 DIRECT ENERGY CONVERSION↗
DOE OSTI2015

DRAFT: Accident Tolerant Fuels Draft Implementation Plan

The ATF Implementation Plan integrates DOE’s objectives and goals with the national laboratory’s expertise and infrastructure in support of the technology development by three industry partners. DOE’s plan is to develop advanced LWR fuels with enhanced accident tolerance in response to the Congressional request and to install a lead fuel assembly containing accident tolerant fuel technology in a U.S. commercial nuclear power plant by 2022. DOE has three contracts in place with each of the principle US commercial nuclear fuel vendors in support of ATF research and development, AREVA Services LLC, General Electric, and Westinghouse LLC. The purpose of the ATF Implementation Plan is to describe the technology development and progress required to insert one (or possible two) concepts as a LFR or LFA in a commercial LWR by 2022. In particular, this document shows the integration between the functional documents guiding ATF development and provides a rough order of magnitude estimate of the required budget from FY2016 through FY2022. It is expected that after FY2022, the needed budget request would significantly decrease as works transitions from Phase 2 to Phase 3, corresponding to a decrease in DOE project responsibility and an increase in industry responsibility and associated funding support.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2015

Developing a laser shockwave model for characterizing diffusion bonded interfaces

The US National Nuclear Security Agency has a Global Threat Reduction Initiative (GTRI) with the goal of reducing the worldwide use of high-enriched uranium (HEU). A salient component of that initiative is the conversion of research reactors from HEU to low enriched uranium (LEU) fuels. An innovative fuel is being developed to replace HEU in high-power research reactors. The new LEU fuel is a monolithic fuel made from a U-Mo alloy foil encapsulated in Al-6061 cladding. In order to support the fuel qualification process, the Laser Shockwave Technique (LST) is being developed to characterize the clad-clad and fuel-clad interface strengths in fresh and irradiated fuel plates. LST is a non-contact method that uses lasers for the generation and detection of large amplitude acoustic waves to characterize interfaces in nuclear fuel plates. However, because the deposition of laser energy into the containment layer on a specimen's surface is intractably complex, the shock wave energy is inferred from the surface velocity measured on the backside of the fuel plate and the depth of the impression left on the surface by the high pressure plasma pulse created by the shock laser. To help quantify the stresses generated at the interfaces, a finite element method (FEM) model is being utilized. This paper will report on initial efforts to develop and validate the model by comparing numerical and experimental results for back surface velocities and front surface depressions in a single aluminum plate representative of the fuel cladding.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2015

An improved methodology for numerical forensics analysis of spent reactor fuel

An improved system was developed to recover the initial parameters and operating conditions from spent nuclear fuel. This work is an expansion of a previous proof-of-concept system developed by the author. The improved system increases the fidelity of the forward model within the spent fuel forensic inverse analysis using two unique methodologies. The first improvement consists of developing a system to accurately create one-group neutron crosssection libraries for any user-specified reactor system. As such, a detailed model using the depletion code MONTEBURNS is developed. During MONTEBURNS execution, cross-section libraries are generated at every user specified burnup step in time. These libraries could be developed for many reactor systems, then housed in a database and used for analyzing spent fuel.

inverse depletion↗
DOE OSTI2016

Development of Radio Frequency Diesel Particulate Filter Sensor and Controls for Advanced Low Pressure Drop Systems to Reduce Engine Fuel Consumption (06B)

This project developed a radio frequencybased sensor for accurate measurement of diesel particulate filter (DPF) loading with advanced low pressuredrop aftertreatment systems. The resulting technology demonstrated engine efficiency improvements through optimization of the combined engineaftertreatment system while reducing emissions, system cost, and complexity to meet the DOE program objectives.

02 PETROLEUM↗
DOE OSTI2020

Accident-Tolerant Fuel

Advanced light water reactor (LWR) fuels have been developed incrementally for more than 60 years before the term Accident Tolerant Fuel (ATF) was created. There are many different categories of ATF concepts, which range from near-term marginal enhancements to fission gas release in fuel or hydrogen pickup in the cladding, to transformational fuel types with new engineered fission product barriers. In this work we characterize these different types of ATF, and give several important examples for each.We conclude that transformational ATF concepts have the greatest potential to enhance the traditional definition of defense-in-depth by enhancing current barriers and/or by providing additional barriers to fission product release. This objective can primarily be achieved by introducing a new fission product barrier that enhances defense-in-depth by design, for example the added barriers to fission product release in some engineered ATF concepts. We recommend future gap analyses and a phenomena identification and ranking to assess the applicability of existing safe acceptable fuel design limits and the standard review plan to specific ATF concepts.

Brown, Nicholas↗
DOE OSTI2014

Neutronics Studies of Uranium-bearing Fully Ceramic Micro-encapsulated Fuel for PWRs

Our study evaluated the neutronics and some of the fuel cycle characteristics of using uranium-based fully ceramic microencapsulated (FCM) fuel in a pressurized water reactor (PWR). Specific PWR lattice designs with FCM fuel have been developed that are expected to achieve higher specific burnup levels in the fuel while also increasing the tolerance to reactor accidents. The SCALE software system was the primary analysis tool used to model the lattice designs. A parametric study was performed by varying tristructural isotropic particle design features (e.g., kernel diameter, coating layer thicknesses, and packing fraction) to understand the impact on reactivity and resulting operating cycle length. Moreover, to match the lifetime of an 18-month PWR cycle, the FCM particle fuel design required roughly 10% additional fissile material at beginning of life compared with that of a standard uranium dioxide (UO 2 ) rod. Uranium mononitride proved to be a favorable fuel for the fuel kernel due to its higher heavy metal loading density compared with UO 2 . The FCM fuel designs evaluated maintain acceptable neutronics design features for fuel lifetime, lattice peaking factors, and nonproliferation figure of merit.

10 SYNTHETIC FUELS↗
DOE OSTI2015

Select Generic Dry-Storage Pilot Plant Design for Safeguards and Security by Design (SSBD) per Used Fuel Campaign

As preparation to the year-end deliverable (Provide SSBD Best Practices for Generic Dry-Storage Pilot Scale Plant) for the Work Package (FT-15LA040501–Safeguards and Security by Design for Extended Dry Storage), the initial step was to select a generic dry-storage pilot plant design for SSBD. To be consistent with other DOE-NE Fuel Cycle Research and Development (FCR&D) activities, the Used Fuel Campaign was engaged for the selection of a design for this deliverable. For the work Package FT-15LA040501–“Safeguards and Security by Design for Extended Dry Storage”, SSBD will be initiated for the Generic Dry-Storage Pilot Scale Plant described by the layout of Reference 2. SSBD will consider aspects of the design that are impacted by domestic material control and accounting (MC&A), domestic security, and international safeguards.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2015

Summary Report of Summer Work: High Purity Single Crystal Growth & Microstructure of Ferritic-Martensitic Steels

Harnessing the power of the nuclear sciences for national security and to benefit others is one of Los Alamos National Laboratory’s missions. MST-8 focuses on manipulating and studying how the structure, processing, properties, and performance of materials interact at the atomic level under nuclear conditions. Within this group, single crystal scintillators contribute to the safety and reliability of weapons, provide global security safeguards, and build on scientific principles that carry over to medical fields for cancer detection. Improved cladding materials made of ferritic-martensitic alloys support the mission of DOE-NE’s Fuel Cycle Research and Development program to close the nuclear fuel cycle, aiming to solve nuclear waste management challenges and thereby increase the performance and safety of current and future reactors.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗