Modelling of Fuel Behaviour in Design Basis Accidents and Design Extension Conditions


Book Description

This publication is the result of an IAEA technical meeting and reports on Member States' capabilities in modelling, predicting and improving their understanding of the behaviour of nuclear fuel under accident conditions. The main results and outcomes of a coordinated research project (CRP) on this topic are also presented.




Fuel Modelling in Accident Conditions


Book Description

This publication summarizes the findings and conclusions of an IAEA coordinated research project (CRP) on fuel modelling in accident conditions, which was initiated under the IAEA Action Plan on Nuclear Safety following the Fukushima accident. The overall aim of the project was to analyse and better understand fuel behavior in accident conditions, with a focus on loss of coolant accidents. In the course of the project the participants used a mixture of data derived from accident simulation experiments, in particular data designed to investigate the fuel behaviour during design basis accident and design extension conditions. They carried out calculations on priority cases selected from a matrix of cases identified at the first research coordination meeting and designed to support their individual priorities. These priority cases were chosen as the best available to help determine which of the many models used in the codes best reflect reality. The CRP provided an ideal platform to compare their code results with others and especially with experimental data, to which they otherwise would not have had access. The achievements made within this CRP fostered new collaborations and enhanced the development and improvement of common models and highlighted differences in the interpretation of some experiments and therefore in the use of the codes ? the so-called user effects.




Design for Reactor Core Safety in Nuclear Power Plants


Book Description

Covers the mechanical, chemical, thermal, hydraulic, neutronic and irradiation considerations important to the safe design of a nuclear reactor core. The core features of commonly used reactor types including light and heavy water reactors, as well as gas cooled reactors, are addressed.




Safety of Nuclear Power Plants


Book Description

On the basis of the principles included in the Fundamental Safety Principles, IAEA Safety Standards Series No. SF-1, this Safety Requirements publication establishes requirements applicable to the design of nuclear power plants. It covers the design phase and provides input for the safe operation of the power plant. It elaborates on the safety objective, safety principles and concepts that provide the basis for deriving the safety requirements that must be met for the design of a nuclear power plant. Contents: 1. Introduction; 2. Applying the safety principles and concepts; 3. Management of safety in design; 4. Principal technical requirements; 5. General plant design; 6. Design of specific plant systems.




Analysis of Options and Experimental Examination of Fuels for Water Cooled Reactors with Increased Accident Tolerance (Actof)


Book Description

There is high interest in new fuel types with increased accident tolerance. These range from using an oxidation resistant coating on zirconium based cladding to alternate fuel and cladding materials. These new fuels/claddings under development must be licensed before being deployed industrially and therefore research is being undertaken to assess their behaviour in various conditions. This publication arises from an IAEA coordinated research project (CRP) dealing with the acquisition of data through experiments on new fuel types and cladding materials and the development of modelling capacity to predict the behaviour of the components and the integral performance of accident tolerant fuel designs under normal and transient conditions. Demonstrations of improvements under severe accident conditions were documented. Several coated cladding materials were produced, tested, characterized and analysed in round robin tests carried out within the CRP. For improvement and validation of fuel performance codes, several benchmarks were organized to compare and analyse predictions of the extended codes. The findings and conclusions of the CRP are summarized in this publication.




Comprehensive Nuclear Materials


Book Description

Materials in a nuclear environment are exposed to extreme conditions of radiation, temperature and/or corrosion, and in many cases the combination of these makes the material behavior very different from conventional materials. This is evident for the four major technological challenges the nuclear technology domain is facing currently: (i) long-term operation of existing Generation II nuclear power plants, (ii) the design of the next generation reactors (Generation IV), (iii) the construction of the ITER fusion reactor in Cadarache (France), (iv) and the intermediate and final disposal of nuclear waste. In order to address these challenges, engineers and designers need to know the properties of a wide variety of materials under these conditions and to understand the underlying processes affecting changes in their behavior, in order to assess their performance and to determine the limits of operation. Comprehensive Nuclear Materials, Second Edition, Seven Volume Set provides broad ranging, validated summaries of all the major topics in the field of nuclear material research for fission as well as fusion reactor systems. Attention is given to the fundamental scientific aspects of nuclear materials: fuel and structural materials for fission reactors, waste materials, and materials for fusion reactors. The articles are written at a level that allows undergraduate students to understand the material, while providing active researchers with a ready reference resource of information. Most of the chapters from the first Edition have been revised and updated and a significant number of new topics are covered in completely new material. During the ten years between the two editions, the challenge for applications of nuclear materials has been significantly impacted by world events, public awareness, and technological innovation. Materials play a key role as enablers of new technologies, and we trust that this new edition of Comprehensive Nuclear Materials has captured the key recent developments. Critically reviews the major classes and functions of materials, supporting the selection, assessment, validation and engineering of materials in extreme nuclear environments Comprehensive resource for up-to-date and authoritative information which is not always available elsewhere, even in journals Provides an in-depth treatment of materials modeling and simulation, with a specific focus on nuclear issues Serves as an excellent entry point for students and researchers new to the field




Light Water Reactor Fuel Enrichment Beyond the Five Per Cent Limit: Perspectives and Challenges


Book Description

The limitation of 235U enrichment is a current concern among IAEA Member States. In response, work has been undertaken to provide a platform to facilitate a comprehensive review of the current status, prospects and challenges associated with the use of fuels having enrichments higher than 5 % 235U in light water reactors. This publication is the outcome of two technical meetings and compiles the results and conclusions in terms of benefits to be obtained from the use of high assay low enriched uranium (HALEU) fuel, with due consideration of safety issues that arise from its use. It details technological options and corresponding issues regarding fuel and core design, safety analysis and assessments relevant to manufacturing, handling, transportation, storage, irradiation, and performance in normal and accident conditions.










IAEA Safety Glossary


Book Description

The IAEA Safety Glossary defines and explains technical terms used in the IAEA Safety Standards and other safety related IAEA publications, and provides information on their usage. The 2018 Edition of the IAEA Safety Glossary is a new edition of the IAEA Safety Glossary, originally issued in 2007. It has been revised and updated to take into account new terminology and usage in safety standards issued between 2007 and 2018. The revisions and updates reflect developments in the technical areas of application of the safety standards and changes in regulatory approaches in Member States.