Publications associées à Nuclear reactor safety system

Neutron-Gamma Noise Measurements in a Zero-Power Reactor Using Organic Scintillators

Andreas Pautz, Vincent Pierre Lamirand, Oskari Ville Pakari

Noise measurements in light water reactor systems aid in generating validation data for integral point kinetic parameter predictions and generating monitoring parameters for reactor safety and safeguards. The CROCUS zero-power reactor has been used to supp ...

Ieee-Inst Electrical Electronics Engineers Inc2024

Gamma noise to non-invasively monitor nuclear research reactors

Andreas Pautz, Vincent Pierre Lamirand, Oskari Ville Pakari, Pavel Frajtag, Tom Mager

Autonomous nuclear reactor monitoring is a key aspect of the International Atomic Energy Agency’s strategy to ensure nonproliferation treaty compliance. From the rise of small modular reactor technology, decentralized nuclear reactor fleets may strain the ...

Nature Research2024

Overview on the Applicability of the ITER/NPP-Like Technologies to the DEMO Plant Electrical System and Promising Alternatives

Damien Fasel, Zhe Chen, Hanwen Zhang, Elena Gaio, Alberto Ferro, Francesco Santoro

The Plant Electrical System (PES) of the European DEMOnstration fusion power plant (DEMO), presently under conceptual design, shall supply power to the loads and deliver net power to the Power Transmission Grid (PTG). Starting from the available requiremen ...

Ieee-Inst Electrical Electronics Engineers Inc2024

Advanced methodologies for modeling and assessment of SFR safety functions

Janos Bodi

The present doctoral work was performed to contribute to the conceptual design development and safety assessment of a Generation IV Sodium Fast Reactor (SFR) in the frame of the European Sodium Fast Reactor Safety Measures Assessment and Research Tools (ES ...

EPFL2022

Compact Thermosyphon Cooling System For High Heat Flux Servers: Validation Of Thermosyphon Simulation Code Considering New Test Data

John Richard Thome, Jackson Braz Marcinichen, Filippo Cataldo, Raffaele Luca Amalfi

Passive, gravity-driven thermosyphons represent a stepchange in technology towards the goal of greatly reducing PUE (Power Usage Effectiveness) of datacenters by replacing energy hungry fans of air-cooling approach with a highly-reliable solution able to d ...

AMER SOC MECHANICAL ENGINEERS2021

Radiation detection and energy conversion in nuclear reactor environments by hybrid photovoltaic perovskites

László Forró, Endre Horvath, Andrzej Sienkiewicz, Bálint Náfrádi, Márton Kollár, Pavao Roko Andricevic

Detection and direct power conversion of high energy and high intensity ionizing radiation could be a key element in next generation nuclear reactor safety systems and space-born devices. For example, the Fukushima catastrophe in 2011 could have been large ...

Elsevier2020

Development of Advanced Methodologies for Monitoring and Modelling of Neutron Noise in Modern LWR Cores

Dionysios Chionis

Nuclear reactors are inherently stochastic systems, in which neutronic and thermal-hydraulic parameters fluctuate continuously even during steady-state conditions. In addition, structural components vibrate due to the coolant hydraulic forces. This stochas ...

EPFL2020

Design Concept and Thermal & x2013;Mechanical Analysis of the Optical Mirror (M3) for the ITER ECH Upper Launcher

Timothy Goodman, René Chavan, Avelino Mas Sanchez

The mirror M3 is a part of the in-vessel quasi-optical beam propagation system for the ITER electron cyclotron heating upper launcher (ECHUL). The millimeter waves are guided through fixed mirror sets (M1, M2, and M3) and the front steering mirror set (M4) ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2020

Systematic Sensitivity and Uncertainty Analysis of Sodium-Cooled Fast Reactor Systems

Friederike Bostelmann

Sodium-cooled fast reactor (SFR) technologies have the potential to guarantee energy supply and to reduce the burden of nuclear waste for future generations. For an adequate simulation of these reactor systems, well-established tools that have so far been ...

EPFL2020

Numerical Simulation and Validation of Aerosol Particle Removal by Water Spray Droplets With OpenFOAM During the Fukushima Daiichi Fuel Debris Retrieval

Hui Liang

In the decommissioning of damaged Fukushima Daiichi reactors, the melted and re-solidified fuel debris in the bottom of the reactor pressure vessel and primary containment vessel need to be cut into small pieces before removing them from reactor buildings. ...

2020

Experimental evaluation and modeling of fatigue of a 316L austenitic stainless steel in high-temperature water and air environments

Wen Chen

Austenitic stainless steels is used in many components of nuclear power plants, particularly in the pipes of cooling systems. Owing to power transients and to start-ups and shutdowns, these components are subjected to thermo-mechanical loadings (low-cycle ...

EPFL2020

Application of causality analysis on nuclear reactor systems

Andreas Pautz, Hakim Ferroukhi, Dionysios Chionis, Abdelhamid Dokhane

Causality analysis is a substantial tool for identifying cause-and-effect links between different components of a system and has been extensively used in various areas of science such as neuroscience, climatology, and econometrics. This analysis is carried ...

American Institute of Physics2019

Effect of dynamic strain ageing on environmental degradation of fracture resistance of low-alloy RPV steels in high-temperature water environments

Philippe Spätig, Hans-Peter Seifert, Zaiqing Que

Elastic plastic fracture mechanics tests on different low-alloy reactor pressure vessel (RPV) steels in air and various simulated light water reactor environments revealed a clear, but moderate reduction of the fracture initiation resistance of RPV steels ...

2019

Design concept and thermal-structural analysis of a high power reflective mm-wave optical mirror (M2) for the ITER ECH-UL

Timothy Goodman, René Chavan, Matteo Vagnoni

Each of the 4 ITER Electron Cyclotron Heating Upper Launcher (ECHUL) features 8 transmission lines used to inject microwave power of up to 1.31 MW per line (at the FCS diamond window), into the plasma at a frequency of 170 GHz. The millimetre waves are gui ...

ELSEVIER SCIENCE SA2019

Extension of the nodal code DYN3D to SFR applications

Evgeny Nikitin

DYN3D is a well-established Light Water Reactor (LWR) simulation tool and is being extended for safety analyses of Sodium cooled Fast Reactors (SFRs) at the Helmholtz-Zentrum Dresden-Rossendorf. This thesis focuses on the first stage of the development pro ...

EPFL2019

High-Temperature Water Effects on the Fracture Behaviour of Low-Alloy Reactor Pressure Vessel Steels

Zaiqing Que

The structural integrity of the reactor pressure vessel (RPV) of light water reactors (LWR) is of utmost importance regarding operation safety and lifetime. High-temperature water (HTW) and hydrogen absorbed from environment, in synergy with irradiation em ...

EPFL2019

Evidence of Be-9 + p nuclear reactions during 2 omega(CH) and hydrogen minority ICRH in JET-ILW hydrogen and deuterium plasmas

Olivier Sauter, Ambrogio Fasoli, Basil Duval, Stefano Coda, Martinus Gijs, Jonathan Graves, Yves Martin, Duccio Testa, Patrick Blanchard, Pierre-Thomas Paul Brun, Alessandro Pau, Henri Weisen, Cristian Sommariva, Richard Pitts, Sun Hee Kim, Jan Horacek, Yann Camenen, Marco Wischmeier, Mikhail Maslov, Javier García Hernández, Miguel Fernández Ruiz, Nicola Vianello, Antonio José Pereira de Figueiredo, Liang Yao, Dalziel Joseph Wilson, Federico Nespoli, José Pedro Rebelo Ferreira Marques, Yao Zhou, David Pfefferlé, Ana Francisca Leal Silva Soares, Daniel Scott Alessi, Davide Galassi, Julio Rodriguez, Jonnathan Cesar Hidalgo Acosta, Jonathan Marc Philippe Faustin, Li Shuai, Pedro Camilo de Oliveira e Silva, Alberto Hernando de Castro, Hamish William Patten, , , , , ,

Pin-by-Pin Treatment of LWR Cores with Cross Section Equivalence Procedures and Higher-Order Transport Methods

Petra Mala

This thesis presents a systematic study on the merits and limitations on using pin-by-pin resolution and transport theory based approaches for nuclear core design calculations. Starting from the lattice codes and an optimal cross section generation scheme, ...

EPFL2018

Modelling of fuel fragmentation, relocation and dispersal during Loss-of-Coolant Accident in Light Water Reactor

Vladimir Vladimirov Brankov

Recent LOCA tests with high burnup fuel at the OECD Halden Reactor Project and at Studsvik demonstrated the susceptibility of the fuel to fragment to small pieces, to relocate and possibly cause a hot-spot effect and to be dispersed in the event of claddin ...

EPFL2017

Status of the ITER Electron Cyclotron Heating and Current Drive System

Timothy Goodman

The electron cyclotron (EC) heating and current drive (H&CD) system developed for the ITER is made of 12 sets of high-voltage power supplies feeding 24 gyrotrons connected through 24 transmission lines (TL), to five launchers, four located in upper ports a ...

Springer2016