Knowledge of basic nuclear physics data is essential for the modelling and safe operation of all types of nuclear facilities. The de facto international standard format, Evaluated Nuclear Data File 6...

The Task Force on Dose Rate Calculations for Irradiated Fuel Assembly was launched in 2015 to assess code predictions of dose rates from bare spent fuel assemblies and to benchmark multiple codes and...

The goal of the Nuclear Energy Agency (NEA) Working Party on Nuclear Criticality Safety (WPNCS) Subgroup on Experimental Needs for Criticality Safety Purposes (SG-5) was to highlight the needs of int...

The NEA launched the Nuclear Education, Skills and Technology (NEST) Framework in partnership with its member countries to help address important gaps in nuclear skills capacity building, knowledge t...

Burn-up credit is a safety approach that accounts for the reduction in the reactivity of configurations with spent nuclear fuel due to the change in their composition after irradiation.

Image: Microscopic examination of U-bearing particles collected at Fukushima-Daiichi, JAEA

Please note that this report was initially published in November 2022 (NEA/NSC/R(2022)3) under erroneous benchmark number IIB; in this updated version (NEA/NSC/R(2022)3/CORR) this has been corrected ...

The NEA organised the first International School on Simulation of Nuclear Reactor Systems (SINUS) on the topic of Reactor single- and multi-physics simulations based on Light Water Reactor (LWR) Unce...

Image: Microscopic examination of U-bearing particles collected at Fukushima-Daiichi, JAEA

TCOFF Phases

First Phase (2017-2020)

The Thermodynamic Characterisation of Fuel Debris and Fission Products ...

The NEA is organising the 16^th Information Exchange Meeting on Actinide and Fission Product Partitioning and Transmutation (16IEMPT) on 24-27 October 2023. The meeting will be held at the NEA offices...

The NEA workshop gathered experts to discuss the challenges and opportunities related to the demise of zero power reactors.

The NEA Working Party on Nuclear Criticality Safety (WPNCS) held its bi-annual meetings in June 2023

Co-organised with the UK Atomic Energy Authority, the course took place on 20-22 June 2023.

High-temperature gas-cooled nuclear reactors are one of the next generation reactor designs. This benchmark consists of a multi-staged code-to-code-to-data thermal hydraulics code validation benchmar...

Under the guidance of the Nuclear Science Committee (NSC), the Working Party on Scientific Issues and Uncertainty Analysis of Reactor Systems (WPRS) studies the reactor physics, fuel performance, an...

TCOFF-2 members discuss future activities.

In the early decades of nuclear reactor development, many countries built and operated zero-power facilities in which many different critical arrangements of materials were studied. These flexible ex...

The annual WPRS Benchmarks Workshops took place on 22-26 May 2023 in Bologna, Italy.

10-year FIDES-II strategic plan will define key research needs in a variety of technical disciplines.

Kick-off workshop of the thermal hydraulic code validation benchmark for high temperature gas-cooled reactors using High Temperature Test Facility (HTTF) data.

The first International School on Simulation of Nuclear Reactor Systems (SINUS) took place on 22-23 May 2023.

WPFM held meetings on 23-25 May 2023.

The FIDES-II framework is designed to do more than just produce data on transient fuel behavior and safety related issues. 

The NEA Second Framework for Irradiation Experiments (FIDES-II) supports the fuel and material experimental needs of nuclear safety regulators, technical support organisations, research institutions ...

Lead-cooled Fast Reactors (LFR) are rather new concepts which have gathered increasing international attention after the Generation-IV International Forum (GIF) selected them as promising candidates ...

Sustained performance of nuclear technology depends on access to a talented and well-qualified workforce, thus it is important to ensure that adequate infrastructures exist for education and training...

The Global Forum on Nuclear Education, Science, Technology and Policy acts as an inclusive network of experts in the nuclear energy sector, primarily from academia, focused on enabling the generation...

The annual Benchmark Workshops of the Working Party on Scientific Issues and Uncertainty Analysis of Reactor Systems will be hosted by the Italian National Agency for New Technologies, Energy and Sus...

Image: QUENCH facility at KIT. Court. KIT. 

The purpose of the QUENCH-ATF project is to investigate the chemical, mechanical and thermal-hydraulics behaviour of ATF claddings in Design Basis Accident...

The NEA nuclear science programme is developed and executed by the Nuclear Science Committee (NSC), comprising high-level scientific experts from all NEA member countries.

This report presents the results of a benchmark study on innovative fuels for fast reactors using fuel performance codes. Irradiation results were shared among participants of the expert group and co...

Monte Carlo criticality calculations involve a two-step procedure based on a stochastic implementation of the power iteration method: first, achieve convergence of the fission source distribution dur...

Since the early 2000s there is an increasing demand from nuclear research, industry, safety and regulation for best-estimate predictions to be provided with their confidence bounds. Consequently, an ...

The NEA thermal hydraulic code validation benchmark for high temperature gas-cooled reactors using HTTF data (HTGR T/H), supervised by the Expert Group on Reactor Core Thermal-Hydraulics and Mechanic...

The Technical Review Groups for both projects met at the NEA headquarters on 3-7 April 2023.

Members of FIDES-II from 12 countries assembled in Prague, Czech Republic, on 17-21 April 2023 for meetings of its Technical Advisory Group and Governing Board.

The WPRS met from 20-24 February 2023.

Expert groups on structural and fuel materials meet to advance materials science activities

Thermodynamic databases and accident prevention

International experts gathered at the NEA for the commencement of the third phase TAF-ID on 16-17 February 2023.

International Fuel Performance Experiments (IFPE) is a data collection of nuclear fuel performance experiments for the purpose of code development and validation.

Development started on DATIF, the DATabase for IFpe, in 2018 in order to enhance accessibility to the IFPE legacy collection of integral fuel performance experiments data, jointly put together by the...

The Shielding Integral Benchmark Archive and Database (SINBAD) database contains compilations for 46 reactor shielding, 31 fusion neutronics and 23 accelerator shielding experiments.

ICSBEP, SINBAD AND IRPhEP Technical Review Group meetings

NEA Working Party on Scientific Issues of Reactor Systems (WPRS) annual meeting, 19-21 February 2020.

ICSBEP, SINBAD AND IRPhEP Technical Review Group meetings, October 2021.

NEA Working Party on Scientific Issues of Reactor Systems (WPRS) annual meeting, 15-19 February 2021.

EGPRS Task Force members met on 3 April 2023.

The continued evolution of fuel and materials technology, fuel performance, optimisation of operational limits, material ageing, failure limits, etc. requires experimental evidence obtained from test...

The Working Party on Scientific Issues and Uncertainty Analysis of Reactor Systems (WPRS) and its expert groups co-ordinate benchmark activities on Reactor Single- and Multi-Physics. The benchmark ac...

This benchmark is organised to examine the models for fission gas release during anticipated operational occurrences (AOOs).

Understanding fuel performance is a key condition for successful reactor operation. Scientific knowledge in this domain was conceived by experimental tests encoded into software routines to ensure ac...

Questions relating to the space, time end energy distribution of neutrons and radiation in different media are the domain of reactor physics.

The modelling and simulation of nuclear systems allow scientists and engineers to probe aspects of the operation of these systems beyond what has been precisely measured. This has numerous applicatio...

Nuclear science is the study of the atomic nuclei and their application, including in nuclear power plants, atomic theory and radiation.

The Working Party on Multi-scale Modelling of Fuels and Structural Material for Nuclear Systems (WPMM) was established to deal with the scientific and engineering aspects of fuels and structural mate...

Under the guidance of the Nuclear Science Committee (NSC) and under the mandate of the Working Party on Multi-scale Modelling of Materials (WPMM), the scope of the Expert Group on Multi-scale Modelli...

View of Dragon Reactor. Photo: AEA Technology.

In 1959, twelve OECD countries began the Dragon Reactor Experiment (DRE) to build a reactor at Winfrith in Dorset, United Kingdom. The Dragon was the fi...

Thermal hydraulics and mechanics deals with the physics and mechanics of the flow and energetic transfer of liquids, and its interactions with the structures around them in large complex systems, suc...

Sodium fast reactors offer the most promising type of reactors to achieve such Generation IV goals at a reasonable time scale given the experience accumulated over the years. However, it is recognise...

The objective of the benchmark was twofold. First, the benchmark aimed to evaluate currently available computational approaches in an effort to understand the strengths and weaknesses of current ther...

The need to refine models for best-estimate calculations based on good-quality experimental data has arisen for various nuclear applications. One of the most extensive and valuable databases availabl...

In 2013, the Expert Group on Reactor Physics and Advanced Nuclear Systems (EGRPANS) published a report that investigated fuel depletion effects in a pressurised water reactor (PWR). This was entitled...

The high-temperature gas-cooled reactor (HTGR) is a Generation IV reactor concept that uses a graphitemoderated gas-cooled nuclear reactor with a once-through uranium fuel cycle. This design permits ...

The purpose of this prismatic High Temperature Reactor (HTR) benchmark is to provide a solution set that can be used in future code benchmarking and to better understand the effects induced by the pr...

This benchmark focuses on FHR reactors with plates and triso fuel. Several phases are planned, starting with neutronics on a simple fuel element simulation without burn-up, and gradually extending to...

In the past decade, a large amount of effort has been made towards the direct simulation of the boiling transition (BT) for Boiling Water Reactor (BWR) fuel bundles. This international benchmark, bas...

In the past decade, a large amount of effort has been made towards the direct simulation of the boiling transition (BT) for boiling water reactor (BWR) fuel bundles. This international benchmark, bas...

In the field of coupled neutronics/thermal-hydraulics computation there is a need to enhance scientific knowledge in order to develop advanced modelling techniques for new nuclear technologies and co...

Recently developed best-estimate computer code systems for modelling 3-D coupled neutronics/thermal-hydraulics transients in nuclear reactors need to be validated against results from experiments and...

This report defines the “OECD/NEA/NSC PBMR Coupled Neutronics/Thermal-hydraulics Transient Benchmark of the PBMR-400 Core Design”. This chapter gives more information on the day-to-day management of ...

Based on the success of the OECD/NRC BFBT Benchmark, Japan released data based on the NUPEC PWR Sub-channel and Bundle Tests (PSBT) Benchmark and asked Pennsylvania State University (PSU) in the Unit...

This report provides the specification for the uncertainty exercises of the international OECD/NEA, NRC and NUPEC BFBT benchmark problem including the elemental task. The specification was prepared j...

Proceedings of the Fourteenth Workshop, 30 October-2 November 2018, Gyeongju, Korea.

Twelfth Workshop Proceedings, Batavia, Illinois, United States, 28-30 April 2014

The brochure provides background information about the NEA.

The understanding of nuclear physics and the associated uncertainties is essential to the modelling of all nuclear systems. Nuclear reaction probabilities, emitted particle energies and angles, fissi...

This benchmark report has been compiled under the guidance of the NEA Working Party on Nuclear Criticality Safety (WPNCS) in the Subgroup on the Role of Integral Experiment Uncertainties and Covarian...

Under the auspices of the NEA Nuclear Science Committee (NSC), the Working Party on Scientific Issues of Advanced Fuel Cycles (WPFC) was established to co-ordinate scientific activities related to ad...

The OECD Nuclear Energy Agency (NEA) Strategic Plan serves as a guiding instrument that reflects the priorities of its member countries as the Agency addresses evolving needs in the exploration and a...

This Strategic Plan is intended to guide the NEA as it seeks to meet the evolving needs of member countries in the application and exploration of nuclear science and technology. The plan includes an ...

Particle accelerators have evolved over the last 50 years from simple devices to powerful machines, and will continued to have an important impact on research, technology and lifestyle. Today, they c...

Particle accelerators have evolved over the last decades from simple devices to powerful machines, and are having an increasingly important impact on research, technology and daily life. Today they c...

Particle accelerators have evolved over the last decades from simple devices to powerful machines, and are having an increasingly important impact on research, technology and daily life. Today they h...

Advanced nuclear fuel cycles to improve the safety, sustainability and economics of nuclear energy are being investigated worldwide. Partitioning and transmutation (P&T) is one of the candidate techn...

Hydrogen has the potential to play an important role as a sustainable and environmentally acceptable source of energy in the 21st century. Present methods for producing hydrogen are mainly based on t...

Hydrogen has the potential to play an important role as a sustainable and environmentally acceptable energy carrier in the 21st century. This report describes the scientific and technical challenges ...

Hydrogen has the potential to play an important role as a sustainable and environmentally acceptable energy carrier in the 21st century. Since natural sources of pure hydrogen are extremely limited, ...

Hydrogen has the potential to play an important role as a sustainable and environmentally acceptable energy source in the 21st century. However, hydrogen does not exist as a gas on earth and thus has...

One of the important issues regarding deterministic transport methods for whole core calculations is that homogenised techniques can introduce errors into results. On the other hand, with modern comp...

The following report is issued by the WPEC Subgroup 27, which builds upon the work of the previous Subgroups 21 and 23, critically reviewing the gamma emission data and providing recommendations to i...

The NEA Annual Report 2019 provides an overview of the status of nuclear power in NEA member countries and illustrative descriptions of the Agency's activities and international joint projects. 2019 ...

Refined models for best-estimate calculations based on good-quality experimental data can improve the understanding of phenomena and the quantification of margins for operating nuclear power reactors...

Saratoga Springs, New York, 6 May 2009 - Meeting summary

Particle transport calculations in three-dimensional configurations are becoming prevalent in nuclear applications. This places a premium on determining the accuracy of numerical solutions to practic...

Since the beginning of benchmark activities, two benchmark workshops took place. The first was held in Madrid, Spain (June 1998), and the second in Garching near Munich, Germany (March 1999). It was ...

The United States and the Russian Federation have each agreed to dispose of 34 tonnes of weapons-grade plutonium that are beyond their defence needs. One effective way to dispose of this plutonium is...

Several NEA Nuclear Science Committee (NSC) activities are concerned with the validation of computation methods and codes as applied to nuclear technology. One of the challenges has been and continue...

Average fuel burn-up in light water reactors (LWRs) has steadily increased with time as technological advances have been made. The practical limit is currently in the region of 50 GWd/t. The main dri...

A summary of the Sixth Symposium on Reactor Noise (SMORN VI), Gatlinburg, United States, 19-24 May 1991

In this benchmark exercise the goal is to test the current state-of-the-art two-dimensional methods of calculating neutron flux to reactor components against the measured data of the VENUS-1 critical...

The OECD/NEA Nuclear Science Committee Task Force on Computing Radiation Dose and Modelling of Radiation-induced Degradation of Reactor Components was set up in November 1995 in response to a request...

The OECD/NEA Task Force on Computing Radiation Dose and Modelling of Radiation-Induced Degradation of Reactor Components (TFRDD) launched two international blind intercomparison exercises to examine ...

Attitudes towards plutonium management vary from country to country and from utility to utility: some regard plutonium as a liability and others as a valuable source of energy.

The purpose of this st...

Rossendorf (Dresden), Germany, 28-30 May 2002

6 October 2002, Seoul, Korea

21-22 January 2003, Barcelona, Spain

Paul Scherrer Institute, Villigen, Switzerland, 15-16 October 2001

In the field of coupled neutronics/thermal-hydraulics computation there is a need to enhance scientific knowledge in order to develop advanced modelling techniques for new nuclear technologies and co...

Workshop Proceedings, 10-12 December 2012

Spent Nuclear Fuel Assay Data for Isotopic Validation - State-of-the-art Report

NEA News is the professional journal of the Nuclear Energy Agency (NEA). It features articles on the latest nuclear energy issues concerning the economic and technical aspects of nuclear energy, nucl...

The following report is issued by WPEC Subgroup 28, which builds upon the work of the previous Subgroup 20 for developing new methods for cross-section covariance evaluation. Subgroup 28 was tasked w...

The present report provides a summary of the experiments analysed and consensuses reached by NEA WPEC Subgroup 41, including final recommendations based on all experimental data available at the time...

As part of a broader spectrum of collaborative activities underpinning nuclear materials research, the Nuclear Energy Agency is supporting worldwide efforts towards the development of advanced materi...

Spent Nuclear Fuel Reprocessing Flowsheet

LACANES – Phase I: Isothermal forced convection case

Primary Radiation Damage in Materials – Review of Current Understanding and Proposed New Standard Displacement Damage Model to Incorporate in Cascade Defect Production Efficiency and Mixing Effects

State-of-the-Art Report on Multi-scale Modelling of Nuclear Fuels

LACANES – Phase II: Natural Convection

The implementation of advanced nuclear systems requires that new technologies associated with the back end of the fuel cycle are developed. The separation of minor actinides from other fuel component...

Document content and format guide for the International Criticality Safety Benchmark Evaluation Project (ICSBEP) – NEA/NSC/DOC(95)03

Criticality Calculations of BWR Spent Fuel in Storage and Transportation, Yoshitaka Naito, Hiroshi Okuno and Yoshihara Ando (JAERI)

Reactivity Prediction Calculations for Infinite Arrays of PWR Mox Fuel Pincells

Results and Analysis of MOX Fuels Depletion Calculations

Numerical benchmark for the analysis of small-sample reactivity experiments

JAERI-M-94-003 Makoto TAKANO (JAERI), January 1994

Burn-up Calculations of BWR Fuel Assemblies for Storage and Transport

Criticality Calculations of BWR Spent Fuel in Storage and Transport, Hiroshi OKUNO, Yoshitaka NAITO, Yoshihira ANDO

Hiroshi OKUNO, Yoshitaka NAITO and Yoshihira ANDO (JAERI)

Simple PWR Spent Fuel Cell (Problem Specification), Makoto TAKANO (JAERI), Michaele BRADY (ORNL), 1991

Effect of Axial Burnup Profile (Infinite fuel pin array) Makoto Takano (JAERI), Michaele Brady (SNL), Alain Santamarina (CEA), June 1993. See NEA/NSC/DOC(96)1

Isotopic Prediction (Problem Specification). Revised, January 1993 Michaele C. Brady<br>See <a href="/html/science/docs/1996/nsc-doc96-06.pdf">NEA/NSC/DOC(96)6</a>.

Nuclide Composition and Neutron Multiplication Factor of a Boiling Water Reactor Spent Fuel Assembly for Burn-up Credit and Criticality Control of Damaged Nuclear Fuel

Impact of Isotopic Inventory Changes due to Control Rod Insertions on Reactivity and the End Effect in PWR UO₂ Fuel Assemblies

Results - Conceptual PWR Spent Fuel Transportation Cask, A. Nouri

JAERI-Research 96-003, M. Takano, H. Okuno, (JAERI), publication date: February 1996

Isotopic Prediction: Final Report, M.D. DeHart (ORNL), M.C. Brady (SNL), C.V. Parks (ORNL). Publication date June 1996. ORNL-6901

The NEA Working Party on Nuclear Criticality Safety (WPNCS) established an Expert Group on Source Convergence in Criticality Safety Analysis (EGSCCSA) to explore the problems of slow convergence and ...

Intermediate Energy Data

Present Status of Minor Actinide Data

As part of the development of advanced nuclear systems, including accelerator-driven systems (ADS) proposed for high-level radioactive waste transmutation and generation IV reactors, heavy liquid met...

Heavy liquid metals such as lead or lead-bismuth have been proposed and investigated as coolants for fast reactors since the 1950s. More recently, there has been renewed interest worldwide in the use...

Many countries have been performing a wide range of research on the partitioning and transmutation (P&T) of minor actinides and fission products. The aim is to provide greater flexibility in terms of...

Future nuclear fuel cycles could effectively address radioactive waste issues with the implementation of partitioning and transmutation (P&T). Previous studies have defined the infrastructure require...

Regional strategies can provide a useful framework for implementing innovative nuclear fuel cycles. The appropriate sharing of efforts and facilities among different countries is necessary in today’s...

Future fuel cycle characteristics, feasibility and acceptability will be crucial for the continued development of nuclear energy, especially in the post-Fukushima context. Fuel cycle choices have bot...

Development of innovative fuels such as homogeneous and heterogeneous fuels, ADS fuels, and oxide, metal, nitride and carbide fuels is an important stage in the implementation process of advanced nuc...

Materials performance is critical to the safe and economic operation of any nuclear system. As the international community pursues the development of Generation IV reactor concepts and accelerator-dr...