Download or read book Conceptual Design of an Annular fueled Superheat Boiling Water Reactor written by Yu-Chih Ko (Ph. D.) and published by . This book was released on 2011 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt: The conceptual design of an annular-fueled superheat boiling water reactor (ASBWR) is outlined. The proposed design, ASBWR, combines the boiler and superheater regions into one fuel assembly. This ensures good neutron moderation throughout the reactor core. A single fuel design is used in the core. Each annular fuel element, or fuel tube, is cooled externally by boiling water and internally by steam. Fuel pellets are made of low enrichment U0 2, somewhat higher than the traditional BWR fuel enrichment. T91 and Inconel 718 are selected as candidates for the cladding material in view of their excellent physical properties and corrosion resistance. The fuel-cladding gap is filled with pressurized helium gas, like the existing lighter water reactor fuels. The ASBWR fuel assembly contains sixty annular fuel elements and one square water rod (occupying a space of four fuel elements) in an 8 by 8 square array. Annular separators and steam dryers are utilized and located above the core in the reactor vessel. Reactor internal pumps are used to adjust the core flow rate. Cruciform control rods are used to control the reactivity of the core, but more of them may be needed than a traditional BWR in view of the harder spectrum. The major design constraints have been identified and evaluated in this work. The ASBWR is found promising to achieve a power density of 50 kW/L and meet all the main safety requirements. This includes a limit on the minimum critical heat flux ratio, maximum fuel and cladding operating temperatures, and appropriate stability margin against density wave oscillations. At the expected superheated steam of 520 °C, the plant efficiency is above 40%, which is substantially greater than the efficiency of 33 to 35% that today's generation of LWRs can achieve. In addition to generating electricity, the ASBWR may also be useful for liquid fuel production or other applications that require high temperature superheated steam. The uncertainties about this design include the performance of cladding materials under irradiation, the attainment of desirable heat transfer ratio between the external and internal coolant channels throughout the fuel cycle, and the response to the traditional transients prescribed as design basis events.

Download or read book Advanced Design Concepts for Pressurized Water Reactor and Boiling Water Reactor High performance Annular Fuel Assemblies written by Tyler Shawn Ellis and published by . This book was released on 2006 with total page 183 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sobering electricity supply and demand projections, coupled with the current volatility of energy prices, have underscored the seriousness of the challenges which lay ahead for the utility industry. This research addresses the impending global need for electricity through the development of advanced annular fuel designs with both internal and external cooling which can achieve higher power densities and hence, higher electricity output from the same basic reactor vessel and containment. Therefore the objectives of this project are to determine the optimal geometrical design parameters of an annular fuel assembly for both PWRs and BWRs for the purpose of achieving maximum power density. It is theorized that utility companies can utilize this design through either retrofitting of their existing reactor facilities or incorporation of the fuel design into new plant concepts. For the case of annular fuel for PWRs, a high performance uranium nitride fuel assembly concept capable of achieving a 50% higher power density was successfully developed. It is shown that a 5% enriched UN annular-fuel assembly can operate at 150% power density for about 50 effective-full-power-days more than that of the nominal 17xl7 solid-fuel-pin assembly operating at 100% power density. Furthermore, neutronic simulation times of this assembly was reduced from approximately 2 days per simulation for a Monte Carlo based analysis to approximately 2 minutes for a deterministic based simulation via the development of an appropriate correction factor for the CASMO-4 neutron transport code. It was shown that a 25% increase in U238 number density for the un-poisoned pins and a 35% increase for the 10 weight percent gadolinium nitride poisoned pins produced the optimal plutonium tracking and infinite multiplication factor simulation.

Download or read book Nuclear Power Reactor Designs written by Jun Wang and published by Elsevier. This book was released on 2023-12-15 with total page 465 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nuclear Power Reactor Designs: From History to Advances analyzes nuclear designs throughout history and explains how each of those has helped to shape and inform the nuclear reactor designs of today and the future. Focused on the structure, systems and relevant components of each reactor design, this book provides the readers with answers to key questions to help them understand the benefits of each design. Each reactor design is introduced, their origin defined, and the relevant research presented before an analysis of its successes, what was learned, and how research and technology advanced as a result are presented. Students, researchers and early career engineers will gain a solid understanding of how nuclear designs have evolved, and how they will continue to develop in the future. Presents reactor designs through history to present day, focusing on key structures, systems and components Provides readers with quick answers about various design principles and rationales Includes new approaches such as the micro-reactor and small-modular reactors

Download or read book American National Standard for Light Water Reactors Fuel Assembly Mechanical Design and Evaluation written by American National Standards Institute and published by . This book was released on 1996 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Prototype Boiling Water Reactor written by J. M. Harrer and published by . This book was released on 1959 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: Design of a nuclear power plant of 50-Mw(e) capacity which can be used to demonstrate advanced performance concepts for boiling water reactors is describe. Included are diagrams and data on core design, mechanical design, and heat transfer and fluid flow. Also included are sections containing information on physics, fuel cycle evaluation, and recommendations. Contains 26 references.

Download or read book Advanced Pressurized Water Reactor Study written by U.S. Atomic Energy Commission. Division of Reactor Development and published by . This book was released on 1959 with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fuel Cycle Program a Boiling Water Reactor Research and Development Program written by and published by . This book was released on 1960-08 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High Performance Light Water Reactor Next Generation Nuclear Power written by Kai Fischer and published by Sudwestdeutscher Verlag Fur Hochschulschriften AG. This book was released on 2009-11 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: The High Performance Light Water Reactor (HPLWR) is a light water reactor with supercritical steam conditions which has been investigated within the 5th Framework Program of the European Commission. Due to the supercritical pressure of 25 MPa, water, used as moderator and as coolant, flows as a single phase through the core and can be directly fed to the turbine. Using the technology of coal fired power plants with supercritical steam conditions, the heat-up in the core is done in several steps to achieve the targeted high steam outlet temperature of 500 C without exceeding available cladding material limits. Based on a first design of a fuel assembly cluster for a HPLWR with a single pass core, the surrounding internals and the reactor pressure vessel are dimensioned for the first time, following the safety standards of the nuclear safety standards commission in Germany. Furthermore, this design is extended to the incorporation of core arrangements with two and three passes. The design of the internals and the RPV are verified using combined mechanical and thermal stress analyses and thermal-hydraulic analyses."

Download or read book High Power Density Development Project written by W. D. Fowler and published by . This book was released on 1960 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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.

Download or read book Innovative Fuel Designs for High Power Density Pressurized Water Reactor written by Dandong Feng (Ph. D.) and published by . This book was released on 2006 with total page 259 pages. Available in PDF, EPUB and Kindle. Book excerpt: (contd.) It is found that the main uncertainty for this design is associated with the heat split between the inner and outer channels due to differences in the thermal resistances in the two fuel-clad gaps. Annular fuel is found to be resistant to flow instabilities, such as Ledinegg instability and density wave oscillation due to high system pressure and one-phase flow along most of the hot channel length. Similar power density uprate is found possible for annular fuel in a hexagonal lattice. Large break loss of coolant accident (LBLOCA) for the reference Westinghouse 4-loop PWR utilizing annular fuel at 150% power is analyzed using RELAP, under conservative conditions. The blowdown peak cladding temperature (PCT) is found to be lower because of the low operating fuel temperature, but the flow rate from the safety injection system needs to be increased by 50% to remove the 50% higher decay heat. Loss of flow analysis also showed better performance of the annular fuel because of its low stored energy. The fuel design that best meets the desired thermal and mechanical features is the spiral cross-geometry rods. The dimensions of this type of fuel that can be applied in the reference core were defined. Thermal-hydraulic whole-core evaluations were conducted with cylindrical fuel rod simplification, and critical heat flux modification based on the heat flux lateral non-uniformity in the cross geometry. This geometry was found to have the potential to increase PWR power density by 50%. However, there are major uncertainties in the feasibility and costs of manufacturing this fuel.

Download or read book REPP written by R. M. Hiatt and published by . This book was released on 1969 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: REPP, a digital computer method for designing pressure water and boiling water reactor cores within specified heat transfer and fuel centerline temperature limits is presented. The method incorporates the Westinghouse W-2 and W-3 empirical correlations and a theoretical hot channel model to predict burnout conditions in a rod bundle. Two geometries are considered; rods in a triangular array and rods in a square lattice. The heat transfer problem solved is a one-dimensional analysis. Pressure drop is considered for four types of fuel-pin spacers. Variable heat generation rate through the fuel-pin and sintering in low density fuels are also included.

Download or read book Advanced Indirect Cycle Water Reactor Studies for Maritime Applications Spike core concept written by and published by . This book was released on 1962 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High Performance Fuel Desing for Next Generation Pressurized Water Reactors written by Mujid S. Kazimi and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of internally and externally cooled annular fule rods for high power density Pressurized Water Reactors is assessed. The assessment included steady state and transient thermal conditions, neutronic and fuel management requirements, mechanical vibration issues, fuel performance issues, fuel fabrication methods and econmic assessment. The investigation was donducted by a team from MIT, Westinghouse, Gamma Engineering, Framatome ANP, and AECL. The analyses led to the conclusion that raising the power density by 50% may be possible with this advanced fuel. Even at the 150% power level, the fuel temperature would be a few hundred degrees lower than the current fuel temperatre. Significant economic and safety advantages can be obtained by using this fuel in new reactors. Switching to this type of fuel for existing reactors would yield safety advantages, but the economic return is dependent on the duration of plant shutdown to accommodate higher power production. The main feasiblity issue for the high power performance appears to be the potential for uneven splitting of heat flux between the inner and outer fuel surfaces due to premature closure of the outer fuel-cladding gap. This could be overcome by using a very narrow gap for the inner fuel surface and/or the spraying of a crushable zirconium oxide film at the fuel pellet outer surface. An alternative fuel manufacturing approach using vobropacking was also investigated but appears to yield lower than desirable fuel density.

Download or read book Nuclear Power written by National Research Council and published by National Academies Press. This book was released on 1992-02-01 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: The construction of nuclear power plants in the United States is stopping, as regulators, reactor manufacturers, and operators sort out a host of technical and institutional problems. This volume summarizes the status of nuclear power, analyzes the obstacles to resumption of construction of nuclear plants, and describes and evaluates the technological alternatives for safer, more economical reactors. Topics covered include: Institutional issues-including regulatory practices at the federal and state levels, the growing trends toward greater competition in the generation of electricity, and nuclear and nonnuclear generation options. Critical evaluation of advanced reactors-covering attributes such as cost, construction time, safety, development status, and fuel cycles. Finally, three alternative federal research and development programs are presented.

Download or read book Analysis of a Power Failure Incident for the Preliminary Conceptual Design of the Small Pressurized Water Reactor written by Charles Francis Bonilla and published by . This book was released on 1959 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analysis of Advanced Fuel Assemblies and Core Designs for the Current and Next Generations of LWRs written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of the project is to design and analyze advanced fuel assemblies for use in current and future light water reactors and to assess their ability to reduce the inventory of transuranic elements, while preserving operational safety. The reprocessing of spent nuclear fuel can delay or avoid the need for a second geological repository in the US. Current light water reactor fuel assembly designs under investigation could reduce the plutonium inventory of reprocessed fuel. Nevertheless, these designs are not effective in stabilizing or reducing the inventory of minor actinides. In the course of this project, we developed and analyzed advanced fuel assembly designs with improved thermal transmutation capability regarding transuranic elements and especially minor actinides. These designs will be intended for use in thermal spectrum (e.g., current and future fleet of light water reactors in the US). We investigated various fuel types, namely high burn-up advanced mixed oxides and inert matrix fuels, in various geometrical designs that are compliant with the core internals of current and future light water reactors. Neutronic/thermal hydraulic effects were included. Transmutation efficiency and safety parameters were used to rank and down-select the various designs.