Download or read book Accident Tolerant Materials for Light Water Reactor Fuels written by Raul B. Rebak and published by . This book was released on 2020-01-06 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accident Tolerant Materials for Light Water Reactor Fuels provides a description of what an accident tolerant fuel is and the benefits and detriments of each concept. The book begins with an introduction to nuclear power as a renewable energy source and the current materials being utilized in light water reactors. It then moves on to discuss the recent advancements being made in accident tolerant fuels, reviewing the specific materials, their fabrication and implementation, environmental resistance, irradiation behavior, and licensing requirements. The book concludes with a look to the future of new power generation technologies. It is written for scientists and engineers working in the nuclear power industry and is the first comprehensive work on this topic. Introduces the fundamental description of accident tolerant fuel, including fabrication and implementation Describes both the benefits and detriments of the various Accident Tolerant Fuel concepts Includes information on the process of materials selection with a discussion of how and why specific materials were chosen, as well as why others failed

Download or read book Accident Tolerant Fuel Concepts for Light Water Reactors written by and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Neutronic and Economic Evaluation of Accident Tolerant Fuel Concepts for Light Water Reactors written by Ian Younker and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Accident tolerant fuels (ATF) are designed to mitigate the detrimental interaction betweenzirconium-alloy cladding and high temperature steam found during beyond design basis accident conditions. Two ATF concepts under consideration are: (1) Coating the exterior ofzirconium-alloy cladding with thin ceramics to limit the zirconium available for reaction withhigh-temperature steam; (2) Replacing zirconium alloys with alternative materials possessingslower oxidation kinetics and reduced hydrogen production. ATF concepts are expected to workwithin the design framework of current and future light water reactors, and for that reason theymust match or exceed the neutronic and economic performance of conventional fuel. This studyanalyzed the neutronic performance and estimated the economic impact of the two previouslydescribed ATF concepts for use in both pressurized water reactors (PWRs) and boiling waterreactors (BWRs).For PWRs findings show ceramic coatings should remain 10-30 m thick to limit neutronicpenalty and reduce fuel costs. For alternative cladding materials, SiC features reduced absorptionwhile other alloys (FeCrAl, TZM, Alloy 33 , and HT-9) enhance absorption compared to reference.Parametric analyses conclude reference performance metrics can be met by employing 90-160m thick clad when the clad inner diameter remains constant or 210-280 m when clad outerdiameter remains constant. For cladding thicknesses between minimum and reference valuesenrichment must increase 0.39-1.74% depending on alloy and geometry. Alternative claddingmaterials may reduce nuclear power plant prot up to $623 M over the 40-year plant lifetime.When incorporated into BWRs, these ATF concepts double neutronic penalties due to largerquantities of zirconium alloy.

Download or read book Assessment of Reactivity Equivalence for Enhanced Accident Tolerant Fuels in Light Water Reactors written by Nathan Michael George and published by . This book was released on 2015 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Metrics for the Evaluation of Light Water Reactor Accident Tolerant Fuel written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The safe, reliable and economic operation of the nation's nuclear power reactor fleet has always been a top priority for the nuclear industry. Continual improvement of technology, including advanced materials and nuclear fuels, remains central to the industry's success. Enhancing the accident tolerance of LWRs became a topic of serious discussion following the 2011 Great East Japan Earthquake, resulting tsunami, and subsequent damage to the Fukushima Daiichi nuclear power plant complex. The overall goal of accident tolerant fuel (ATF) development is to identify alternative fuel system technologies to further enhance the safety, competitiveness, and economics of commercial nuclear power. The complex multiphysics behavior of LWR nuclear fuel in the integrated reactor system makes defining specific material or design improvements difficult; as such, establishing desirable performance attributes is critical in guiding the design and development of fuels and cladding with enhanced accident tolerance. The U.S. Department of Energy is sponsoring multiple teams to develop ATF concepts within multiple national laboratories, universities, and the nuclear industry. Concepts under investigation offer both evolutionary and revolutionary changes to the current nuclear fuel system. This paper summarizes technical evaluation methodology proposed in the U.S. to aid in the optimization and down-selection of candidate ATF designs. This methodology will continue to be refined via input from the research community and industry, such that it is available to support the planned down-selection of ATF concepts in 2016.

Download or read book Advanced Fuels Campaign Light Water Reactor Accident Tolerant Fuel Performance Metrics Executive Summary written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Research and development (R & D) activities on advanced, higher performance Light Water Reactor (LWR) fuels have been ongoing for the last few years. Following the unfortunate March 2011 events at the Fukushima Nuclear Power Plant in Japan, the R & D shifted toward enhancing the accident tolerance of LWRs. Qualitative attributes for fuels with enhanced accident tolerance, such as improved reaction kinetics with steam resulting in slower hydrogen generation rate, provide guidance for the design and development of fuels and cladding with enhanced accident tolerance. A common set of technical metrics should be established to aid in the optimization and down selection of candidate designs on a more quantitative basis. "Metrics" describe a set of technical bases by which multiple concepts can be fairly evaluated against a common baseline and against one another. This report describes a proposed technical evaluation methodology that can be applied to evaluate the ability of each concept to meet performance and safety goals relative to the current UO2 - zirconium alloy system and relative to one another. The resultant ranked evaluation can then inform concept down-selection, such that the most promising accident tolerant fuel design option(s) can continue to be developed toward qualification.

Download or read book Analysis and Optimization of a New Accident Tolerant Fuel Called Fuel in fibers written by Briana Diane Hiscox and published by . This book was released on 2018 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 2011 Fukushima Daiichi accident highlighted the weakness of the current nuclear fuel and motivated R&D of accident tolerant fuels. Accident tolerant fuels (ATF) are fuels that can tolerate loss of active cooling in the core of light water reactors (LWRs) for a considerably longer period of time while maintaining or improving the fuel performance during normal operations. Fully Ceramic Microencapsulated (FCM) fuel is an ATF concept aimed at significantly increasing the fission product retention capability of nuclear fuel at high temperatures. The FCM concept is made up of fuel particles surrounded by multilayers of ceramic material similar to the TRISO fuel concept. The fuel particles are embedded in a SiC matrix in cylindrical pellet geometry which gives the fuel its high temperature corrosion resistance. However, when implementing the FCM concept in a conventional PWR fuel geometry, it is not possible to maintain an 18 month fuel cycle length and remain below the proliferation enrichment limit of 20 w/o U235. This is a critical challenge that needs to be overcome in order to benefit from the high temperature fission product retention capability of FCM-type ATF concepts. Therefore, this work aims at investigating the potential benefits of a new accident tolerant fuel, Fuel-in-Fibers (F-in-F) concept. The Fuel-in-Fibers concept was created by Free Form Fibers, a laser chemical vapor deposition direct manufacturing company. It aims to combine the same robust fission product retention and high temperature stability as the FCM fuel concept while drastically decreasing the necessary fuel enrichment. This is done by designing a fuel fiber in cylindrical geometry as opposed to spherical particles to increase the packing fraction within a cylindrical pellet. The direct manufacturing allows for minimization of the volume occupied by the SiC matrix as well as direct deposition of high density fuels like uranium nitride (UN). Assembly level calculations in the Monte Carlo code SERPENT determined that the Fuel-in-Fibers concept could maintain a typical PWR cycle length with less than 20 w/o U235 (LEU) enrichment. The fibers in the fuel pellet were then homogenized for use in lattice physics code CASMO and core simulator code SIMULATE3. The SIMUALTE full core simulation showed that the Fuel-in- Fibers design required enrichments of 8% and 6% for UO2 and UN as fuels, respectively. Overall, the full core analysis of a standard 4-loop Westinghouse PWR showed Fuel-in-Fibers concept has similar behavior as the conventional fuel. Due to the high fissile enrichments, the calculated radial power peaking factors were higher in Fuel-in-Fibers concept. This may result in decrease of the coolant outlet temperature by 5 K in order to maintain safety margins. The shutdown margin analysis showed that using B4C instead AgInCd control rods is needed. A design optimization was also performed to calculate the ideal geometry for Fuel-in-Fibers concept. An in-house MATLAB single channel code, built to evaluate PWR Thermal Hydraulic and Structural performance, was used to vary the fuel pin Pitch and Pitch-to-Diameter ratio (P/D Ratio). The results showed that a smaller pitch and larger diameter of 13.2 mm and 12 mm, respectively will improve the Fuel-in-Fibers concept enrichment requirements. A simplified economic analysis based on highly uncertain fabrication cost estimates was performed. The economics analysis determined that the fuel in fiber design is estimated to cost more than current UO2 fuel by 1.25x – 15x due to the increased enrichment and fabrication costs but may be offset by the additional safety margins provided by the Fuel-in-Fibers concept.

Download or read book Development of Advanced Accident Tolerant Fuels for Commercial Light Water Reactors written by and published by . This book was released on 2014 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: The safe, reliable and economic operation of the nation's nuclear power reactor fleet has always been a top priority for the United States' nuclear industry. Continual improvement of technology, including advanced materials and nuclear fuels remains central to industry's success. Decades of research combined with continual operation have produced steady advancements in technology and yielded an extensive base of data, experience, and knowledge on light water reactor (LWR) fuel performance under both normal and accident conditions. Thanks to efforts by both the U.S. government and private companies, nuclear technologies have advanced over time to optimize economic operations in nuclear utilities while ensuring safety. One of the missions of the U.S. Department of Energy Office of Nuclear Energy (DOE-NE) is to develop nuclear fuels and claddings with enhanced accident tolerance. In 2011, following the Great East Japan Earthquake, resulting tsunami, and subsequent damage to the Fukushima Daiichi nuclear power plant complex, enhancing the accident tolerance of LWRs became a topic of serious discussion. As a result of direction from the U.S. Congress, DOE-NE initiated Accident Tolerant Fuel (ATF) development as a primary component of the Fuel Cycle Research & Development (FCRD) Advanced Fuels Campaign (AFC). Prior to the unfortunate events at Fukushima, the emphasis for advanced LWR fuel development was on improving nuclear fuel performance in terms of increased burnup for waste minimization, increased power density for power upgrades, and increased fuel reliability. Fukushima highlighted some undesirable performance characteristics of the standard fuel system during severe accidents, including accelerated hydrogen production under certain circumstances. Thus, fuel system behavior under design basis accident and severe accident conditions became the primary focus for advanced fuels while still striving for improved performance under normal operating conditions to ensure that proposed new fuels will be economically viable. The goal of the ATF development effort is to demonstrate performance with a lead test assembly or lead test rod (LTR) or lead test assembly (LTA) irradiation in a commercial power reactor by 2022. Research and development activities are being conducted at multiple DOE national laboratories, universities and within industry with support from the DOE program. A brief program overview and status are provided.

Download or read book Enhanced Accident Tolerant LWR Fuels written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Department of Energy (DOE) Fuel Cycle Research and Development (FCRD) Advanced Fuels Campaign (AFC) is conducting research and development on enhanced Accident Tolerant Fuels (ATF) for light water reactors (LWRs). This mission emphasizes the development of novel fuel and cladding concepts to replace the current zirconium alloy-uranium dioxide (UO2) fuel system. The overall mission of the ATF research is to develop advanced fuels/cladding with improved performance, reliability and safety characteristics during normal operations and accident conditions, while minimizing waste generation. The initial effort will focus on implementation in operating reactors or reactors with design certifications. To initiate the development of quantitative metrics for ATR, a LWR Enhanced Accident Tolerant Fuels Metrics Development Workshop was held in October 2012 in Germantown, MD. This paper summarizes the outcome of that workshop and the current status of metrics development for LWR ATF.

Download or read book Cold Spray Coatings written by Pasquale Cavaliere and published by Springer. This book was released on 2017-11-08 with total page 566 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book combines the contributions of experts in the field to describe the behavior of various materials, micromechanisms involved during processing, and the optimization of cold-spray technology. It spans production, characterization, and applications including wear resistance, fatigue, life improvement, thermal barriers, crack repair, and biological applications. Cold spray is an innovative coating technology based on the kinetic energy gained by particles sprayed at very high pressures. While the technique was developed in the 1990s, industrial and scientific interest in this technology has grown vastly in the last ten years. Recently, many interesting applications have been associated with cold-sprayed coatings, including wear resistance, fatigue life improvement, thermal barriers, biological applications, and crack repair. However, many fundamental aspects require clarification and description.

Download or read book Enhanced Accident Tolerant LWR Fuels National Metrics Workshop Report written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Thermal Hydraulics of Accident Tolerant Fuel Concepts and a Preliminary Demonstration of CASL s Coupled Tools for BWRs written by Jacob Preston Gorton and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the 2011 accident at the Daiichi nuclear power plant in Fukushima, Japan, there has been a worldwide effort to develop so-called accident tolerant fuel (ATF) technologies to enhance safety during design basis and beyond design basis accidents. Part of the ATF development effort involves replacing much of the zirconium-based materials in light water reactors (LWRs). This is due to the accelerated oxidation rate of zirconium at high temperatures potentially experienced during severe accidents, which led to the build-up of hydrogen gas and eventual explosions that occurred at the Daiichi nuclear power plant. To be considered as a possible alternative to zirconium, an ATF candidate material must not only have greater oxidation resistance but must also have equal or better performance than zirconium in reactor operations and safety. Two candidate materials that may meet these requirements are iron-chromium-aluminum (FeCrAl) alloys and silicon carbide fiber-reinforced, silicon carbide matrix composites (SiC/SiC). Two studies on ATF concepts are presented in this thesis, which focus on using computer simulations to evaluate the use of FeCrAl as the fuel rod cladding material in a pressurized water reactor (PWR) and the use of SiC/SiC as the fuel assembly channel box material in a boiling water reactor (BWR). Both of these studies are performed using computer modeling, which is one of the first steps for evaluating new design concepts and eventually integrating them into existing reactors. Developing tools that can accurately predict the performance of nuclear reactors with high fidelity is the goal of the Consortium for Advanced Simulation of Light Water Reactors (CASL). Also included in this thesis is a preliminary demonstration of neutronic-to-thermal-hydraulic coupled BWR simulations performed using the CASL tools MPACT and CTF. In the first study, a model of a PWR fuel assembly was created to predict the critical heat flux (CHF) of FeCrAl fuel rod cladding during an imposed 50% overpower condition, which may be representative of an accident condition. CHF is a critical parameter to evaluate for ATF candidate materials because reaching CHF in a fuel rod can cause a rapid increase in temperature in the reactor that may lead to bursting of the cladding and a loss of ability to cool the core. Current correlations used for predicting flow boiling CHF in reactors are not dependent on material or surface characteristics, but this study showed that preliminary pool boiling results could be used to modify existing CHF correlations to make them more applicable to a given material, such as FeCrAl. Preliminary transient flow boiling experiments are also analyzed in this thesis for Inconel 600 and Stainless Steel 316, which pave the way for future flow boiling experiments using FeCrAl. In the second study, BWR fuel assembly models were created with a SiC/SiC channel box to predict a spatial temperature and fast neutron flux distribution in the channel box. The temperature and fast flux distributions were then used as boundary conditions for a finite element model of the channel box created by Oak Ridge National Laboratory to determine the deflection of the channel box due to temperature and neutron flux gradients. It was found in this study that the deflection of the channel box, which was mainly a product of the nonuniform fast flux distribution causing a swelling gradient within the channel box, may lead to interference with control blades in BWR cores. The work presented in this thesis provides new information on two ATF concepts and helps lay the groundwork for future evaluations. Detailed computational evaluations are an important step in the progression and application of these concepts that have the potential to increase the safety of nuclear reactors. The development of high-fidelity computational tools like MPACT/CTF is important for providing accurate simulated results that can be used in advancing the development of ATF concepts.

Download or read book Accident Tolerant Materials for Light Water Reactor Fuels written by Raul B. Rebak and published by Elsevier. This book was released on 2020-01-10 with total page 237 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accident Tolerant Materials for Light Water Reactor Fuels provides a description of what an accident tolerant fuel is and the benefits and detriments of each concept. The book begins with an introduction to nuclear power as a renewable energy source and the current materials being utilized in light water reactors. It then moves on to discuss the recent advancements being made in accident tolerant fuels, reviewing the specific materials, their fabrication and implementation, environmental resistance, irradiation behavior, and licensing requirements. The book concludes with a look to the future of new power generation technologies. It is written for scientists and engineers working in the nuclear power industry and is the first comprehensive work on this topic. Introduces the fundamental description of accident tolerant fuel, including fabrication and implementation Describes both the benefits and detriments of the various Accident Tolerant Fuel concepts Includes information on the process of materials selection with a discussion of how and why specific materials were chosen, as well as why others failed

Download or read book Nuclear Fuel Safety Criteria written by OECD Nuclear Energy Agency and published by OECD Publishing. This book was released on 2001 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presents brief descriptions of 20 fuel-related safety criteria along with both the rationale for having such criteria and possible new design and operational issues which could have an effect on them.

Download or read book Enhanced Accident Tolerant Fuels for LWRS A Preliminary Systems Analysis written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The severe accident at Fukushima Daiichi nuclear plants illustrates the need for continuous improvements through developing and implementing technologies that contribute to safe, reliable and cost-effective operation of the nuclear fleet. Development of enhanced accident tolerant fuel contributes to this effort. These fuels, in comparison with the standard zircaloy - UO2 system currently used by the LWR industry, should be designed such that they tolerate loss of active cooling in the core for a longer time period (depending on the LWR system and accident scenario) while maintaining or improving the fuel performance during normal operations, operational transients, and design-basis events. This report presents a preliminary systems analysis related to most of these concepts. The potential impacts of these innovative LWR fuels on the front-end of the fuel cycle, on the reactor operation and on the back-end of the fuel cycle are succinctly described without having the pretension of being exhaustive. Since the design of these various concepts is still a work in progress, this analysis can only be preliminary and could be updated as the designs converge on their respective final version.

Download or read book Analysis of the FeCrAl Accident Tolerant Fuel Concept Benefits During BWR Station Blackout Accidents written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Iron-chromium-aluminum (FeCrAl) alloys are being considered for fuel concepts with enhanced accident tolerance. FeCrAl alloys have very slow oxidation kinetics and good strength at high temperatures. FeCrAl could be used for fuel cladding in light water reactors and/or as channel box material in boiling water reactors (BWRs). To estimate the potential safety gains afforded by the FeCrAl concept, the MELCOR code was used to analyze a range of postulated station blackout severe accident scenarios in a BWR/4 reactor employing FeCrAl. The simulations utilize the most recently known thermophysical properties and oxidation kinetics for FeCrAl. Overall, when compared to the traditional Zircaloy-based cladding and channel box, the FeCrAl concept provides a few extra hours of time for operators to take mitigating actions and/or for evacuations to take place. A coolable core geometry is retained longer, enhancing the ability to stabilize an accident. Finally, due to the slower oxidation kinetics, substantially less hydrogen is generated, and the generation is delayed in time. This decreases the amount of non-condensable gases in containment and the potential for deflagrations to inhibit the accident response.

Download or read book Application of Advanced Fuel Concepts for Use in Innovative Pressurized Water Reactors written by Nathan Christopher Andrews and published by . This book was released on 2015 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work addresses several specific knowledge gaps that exist in the use of alternative fuel and cladding combinations in a pressurized water reactor (PWR) environment. In the switch from a UO2 with zirconium-based cladding to any other combination, there is a multitude of questions that need to be answered. This work examines three of these knowledge gaps: (1) the disposition of weapons-grade plutonium in thorium and silicon carbide cladding, (2) economics of accident tolerant fuel (ATF) claddings and (3) breeding of plutonium in uranium nitride fuel. Burning weapons-grade plutonium in a standard pressurized water reactor (PWR) using thoria as a fuel matrix has been compared to using urania. Two cladding options were considered: a 0.76 mm thick silicon carbide ceramic matrix composite (SiC CMC) and 0.57 mm thick standard Zircaloy cladding. A large benefit was found in using thoria compared to urania in terms of plutonium percentage and mass burned. A slightly smaller mass of plutonium is required in a core with SiC CMC cladding, due to its lower neutron absorption compared to Zircaloy. The thorium system was also better from a non-proliferation viewpoint, resulting in less fissile mass at discharge and more fissile mass burned over an assembly's lifetime. A limited safety comparison was made for two reactivity insertion accidents: (1) highest worth rod ejection accident (REA) and (2) main steam line break (MSLB). The MSLB accident demonstrated a safe value for the minimum departure from nucleate boiling ratio. The maximum enthalpy added to the fuel during the REA was also below current regulatory limits for PWRs. This indicates that the more negative moderator temperature coefficients of thoria-plutonia and urania-plutonia fuel, compared to a typical PWR design, were not limiting. For an ATF cladding to replace zirconium alloys, it must be economically viable by having similar fuel cycle costs to today's materials. Four proposed materials are examined: stainless steel (SS), FeCrAl alloy, molybdenum (Mo) and SiC CMC, each having its own development time and costs. The chosen cladding thicknesses were dependent on strength and manufacturing constraints. It was found that all options may end up requiring higher enrichment than zirconium-based claddings for the same fuel cycle length. If the present value of avoiding a reactor accident with a large radioactivity release is estimated using past experience for LWR large accidents and if it is assumed that ATF cladding is able to prevent such release, there is a definite net economic benefit relative to typical Zircaloy cladding only in using SiC, since it only results in a small fuel cycle cost increase. There is only a marginal benefit in using SiC to prevent a core-only loss without radioactivity release (TMI-type) accident and a large loss using metallic ATF concepts. The thermal hydraulic and neutronic feasibility of a nitride fueled pressurized water reactor (PWR) breeder design were examined. Because of its higher fuel density, nitride fuel would be preferable to traditional oxide fuel in attempting to achieve breeding in a PWR. The design chosen uses large hexagonal assemblies with 14 inner seed pin rows and 4 outer blanket pin rows. In this design, reactor grade plutonium of 12.75 wtHM was used as fuel. Nitride was also simulated as being 100% N-15, to limit neutronic penalties and C-14 production. The as specified assembly model only achieved a fissile inventory ratio (FIR) value above 1.0 when the thimble regions were assumed to be voided, which lowers the H/HM ratio in the assembly. This led to FIR values above 1.0 for the oxide, 85% theoretical density nitride (N85) and 95% theoretical density nitride (N95). All were at an FIR of 1.03 at 35 MWd/kgHM. However, the single batch discharge burnup of the voided assembly in MWd/kgHM was 32.2 for N95, 24.5 for N85, while only 15.6 for the oxide.