IAEA activities and international collaborations

With a well-defined area of focused research and encouraging information exchange, the International Atomic Energy Agency (IAEA) conducts various coordinated research activities (CRA) and brings together various scientists from developing and developed countries. Within this established programme on CRAs, IAEA has been leading efforts on several Coordinated Research Projects on fast neutron systems. The presentation will briefly discuss and summarize various concluded, ongoing and planned CRPs, outlining their objectives and outcomes and showcase some key results. The CRPs are mainly in the field of modelling and simulations, covering neutronics, thermal hydraulics and multi-physics phenomena in fast reactors. Information on participating and contributing to such international collaboration projects, which aim to support not only wide R&D efforts but also various PhD studies in the universities, will also be provided

MONTE CARLO SIMULATION OF NEUTRONICS START-UP TESTS AT CHINA EXPERIMENTAL FAST REACTOR (CEFR)

China Experimental Fast Reactor (CEFR) is a small size sodium-cooled fast reactor (SFR) with a high neutron leakage core fueled by uranium oxide. The CEFR core with 20 MW(e) power reached its first criticality in July 2010, and several start-up tests were conducted from 2010 to 2011. The China Institute of Atomic Energy (CIAE) proposed to release some of the neutronics start-up test data for the IAEA benchmark within the scope of the IAEA’s coordinated research activities through the coordinated research project (CRP) on “Neutronics Benchmark of CEFR Start-Up Tests”, launched in 2018. This benchmark aims to perform validation and verification of the physical models and the neutronics simulation codes by comparing calculation results against collected experimental data. The six physics start-up tests considered for this CRP include evaluation of the criticality, control rod worth, void reactivity, temperature coefficient, swap reactivity, and foil irradiation. Twenty-nine participating research organizations are performing independent blind calculations during the first phase of the project. As a part of this coordinated research, IAEA performed neutronics calculations using Monte Carlo code SERPENT. Two kinds of 3D core models, homogenous and heterogeneous, were calculated using SERPENT, with ENDF/B-VII.0 continuous energy library. Preliminary results with a reasonably good estimation of criticality, as well as theoretically sound results of other five test cases, are available. The paper will discuss the core modelling assumptions, challenges and key findings of modelling a dense SFR core, preliminary results of the first phase of the CRP, heterogeneity impact analysis between homogenous core models and heterogeneous core models and future work to be performed as a part of this four-year project

CLINICAL SIGNIFICANCE OF ANTENALHEMOGLOBIN TYPES DETERMINATION IN PROGNOSIS OF EARLY ADAPTATION IN PREMATUPE NEWBORNS

(Voprosy sovremennoi pediatrii — Current Pediatrics. 2009;8(2):120-122

Neutronic Analysis of Start-Up Tests at China Experimental Fast Reactor

The China Experimental Fast Reactor (CEFR) is a small, sodium-cooled fast reactor with 20 MW(e) of power. Start-up tests of the CEFR were performed from 2010 to 2011. The China Institute of Atomic Energy made some of the neutronics start-up-test data available to the International Atomic Energy Agency (IAEA) as part of an international neutronics benchmarking exercise by distributing the experimental data to interested organizations from the member states of the IAEA. This benchmarking aims to validate and verify the physical models and neutronics simulation codes with the help of the recorded experimental data. The six start-up tests include evaluating criticality, control-rod worth, reactivity effects, and neutron spectral characteristics. As part of this coordinated research, the IAEA performed neutronics calculations using the Monte Carlo codes Serpent 2 and OpenMC, which can minimize modeling assumptions and produce reference solutions for code verification. Both codes model a three-dimensional heterogeneous core with an ENDF/B-VII.1 cross-section library. This study presents the calculation results with a well-estimated criticality and a reasonably good estimation of reactivities. The description and analysis of the core modeling assumptions, challenges in modeling a dense SFR core, results of the first phase of this project, and comparative analysis with measurements are presented

MONTE CARLO SIMULATION OF NEUTRONICS START-UP TESTS AT CHINA EXPERIMENTAL FAST REACTOR (CEFR)

China Experimental Fast Reactor (CEFR) is a small size sodium-cooled fast reactor (SFR) with a high neutron leakage core fueled by uranium oxide. The CEFR core with 20 MW(e) power reached its first criticality in July 2010, and several start-up tests were conducted from 2010 to 2011. The China Institute of Atomic Energy (CIAE) proposed to release some of the neutronics start-up test data for the IAEA benchmark within the scope of the IAEA’s coordinated research activities through the coordinated research project (CRP) on “Neutronics Benchmark of CEFR Start-Up Tests”, launched in 2018. This benchmark aims to perform validation and verification of the physical models and the neutronics simulation codes by comparing calculation results against collected experimental data. The six physics start-up tests considered for this CRP include evaluation of the criticality, control rod worth, void reactivity, temperature coefficient, swap reactivity, and foil irradiation. Twenty-nine participating research organizations are performing independent blind calculations during the first phase of the project. As a part of this coordinated research, IAEA performed neutronics calculations using Monte Carlo code SERPENT. Two kinds of 3D core models, homogenous and heterogeneous, were calculated using SERPENT, with ENDF/B-VII.0 continuous energy library. Preliminary results with a reasonably good estimation of criticality, as well as theoretically sound results of other five test cases, are available. The paper will discuss the core modelling assumptions, challenges and key findings of modelling a dense SFR core, preliminary results of the first phase of the CRP, heterogeneity impact analysis between homogenous core models and heterogeneous core models and future work to be performed as a part of this four-year project

Stochastic non-uniformity of temperature fields in deformed sub-assemblies of fast reactors

Translated from Russian (FEI--1678, Obninsk, 1985)SIGLEAvailable from British Library Document Supply Centre- DSC:9091.9F(RISLEY-Trans--5217)T / BLDSC - British Library Document Supply CentreGBUnited Kingdo

IAEA INITIATIVE ON OPEN-SOURCE NUCLEAR CODES FOR REACTOR ANALYSIS

The International Atomic Energy Agency (IAEA) aims to support and strengthen its Member States' capabilities in the field of advanced reactors' modelling and simulation. Several years of work have been performed by many institutions on the creation of modern open-source tools for reactor analysis and the trend towards open-source codes and open-access data is evident in the scientific community. In 2021, the IAEA initiated activities to support, coordinate, and create synergies in the development of open-source nuclear codes for reactor analysis. As an outcome of this initiative, the IAEA has already established a platform available to all IAEA Member States: The Open-source Nuclear Codes for Reactor Analysis (ONCORE). This platform is attractive for developers around the world, who are seeking collaboration in the area and for exploring new nuclear codes for research and development as well as education and training activities. This paper highlights the recent activities organized by the IAEA within the framework of the ONCORE initiative