Publications associées à Determination of within-rod caesium and europium isotopic distributions in high burnup fuel rods through computerised gamma-ray emission tomography

Atomic level insight into irradiation effects in nuclear fuel materials

Microstructural evolution during in-pile irradiation, radiation damage effects and fission products behavior in UO2 nuclear fuel are key issues in understanding and for the modeling of the performance as well as safety characteristics of nuclear fuels in t ...

EPFL2024

Experimental study and interpretative modelling of the Power Exhaust in Configurations with Multiple X-Points in TCV

Sophie Danielle Angelica Gorno

Nuclear fusion presents a promising clean energy source to mitigate future energy crises, with magnetic confinement fusion well-positioned to provide a baseload scenario to power future reactors. The unmitigated power exhaust of such reactors threatens its ...

EPFL2024

Intra-pin Reaction Rate Measurements in the CROCUS Experimental Reactor

Andreas Pautz, Oskari Ville Pakari, Vincent Pierre Lamirand, Mathieu Hursin, Thomas Jean-François Ligonnet, Tom Mager

In response to the need for validating high-fidelity deterministic neutronics solvers capable of providing pin-resolved neutron flux distributions, intra-pin reaction rates measurements were performed in the CROCUS experimental reactor. A specially designe ...

2024

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

Andreas Pautz, Oskari Ville Pakari, Vincent Pierre Lamirand

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

Innovative thermophysical characterization of an ATF composite cladding: the case of silicon carbide

Andrea Cavaliere

Nuclear power is a powerful technology that plays an important role in the fight against climate change, and research is continuously engaged in studies that could further improve its safety. After the Fukushima accident, Accident Tolerant Fuels research h ...

EPFL2024

Gamma noise to non-invasively monitor nuclear research reactors

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

Monte Carlo analysis of BWR geometries using a cycle check-up methodology

Abdelhamid Dokhane, Hakim Ferroukhi, Alexander Vasiliev, Mathieu Hursin, Dimitri Rochman

Recent fuel anomalies at a Swiss power plant have motivated the development at PSI of the "Cycle Check-Up" (CHUP) methodology which consists in performing Monte Carlo transport calculations using nuclide compositions and thermal-hydraulic boundary conditio ...

Pergamon-Elsevier Science Ltd2023

Design and operational guidelines of solar-driven catalytic conversion of CO2 and H2 to fuels

Sophia Haussener, Sha Li

Sunlight-powered catalytic conversion of CO2 and (green) H2 into fuels and chemicals via Sabatier and reverse water gas shift (RWGS) processes offers a promising solution to reduce greenhouse gas emissions and increase renewable energy utilization. The suc ...

ELSEVIER SCI LTD2023

Extension of the OFFBEAT fuel performance code to finite strains and validation against LOCA experiments

Andreas Pautz, Alessandro Scolaro, Carlo Fiorina, Edoardo Luciano Brunetto

The mechanical analysis of nuclear fuel behavior under base-irradiation conditions has traditionally been performed adopting the small-strain approximation. However, many cases of interest for fuel behavior involve the occurrence of large rod deformations ...

ELSEVIER SCIENCE SA2023

Extension of GeN-Foam to departure from nucleate boiling prediction and validation against the OECD/NRC PSBT benchmark

Alessandro Scolaro, Carlo Fiorina, Hao Qin, Yuhang Niu

The prediction of departure from nucleate boiling (DNB) has always been a crucial aspect of thermal-hydraulic codes for the analysis of Light Water Reactors. In this paper, GeN-Foam, a multi-physics code developed based on OpenFOAM, has been enhanced to in ...

Elsevier Science Sa2023

Design of an Instrumented Fuel Rod for Intra-pin Neutron Flux Measurements in the CROCUS Experimental Reactor

Andreas Pautz, Vincent Pierre Lamirand, Mathieu Hursin, Thomas Jean-François Ligonnet, Won Dong Shin, Tom Mager

In response to the need for validating high-fidelity deterministic neutronics solvers capable of pin-resolved neutron flux distributions, an instrumented fuel rod was designed for the experimental reactor CROCUS, operated by EPFL’s Laboratory for Reactor P ...

2023

Gamma-Blind Fast Neutron Detection for Spent Nuclear Fuel Characterization

Alexander Wolfertz

In this thesis, the development and testing of a system for measuring the axial distribution of fast neutron emission of spent nuclear fuel rods is presented. Emphasis is placed on the novel fast neutron detector used which can reliably work in extremely h ...

EPFL2023

A holistic investigation of photocatalytic hydrogen generation

Sangram Ashok Savant

Photocatalytic (PC) solar hydrogen production is a promising way to provide green hydrogen using only sunlight and abundant reactants such as water. PC approaches use catalytically active semiconductor particles suspended in liquid electrolytes. The partic ...

EPFL2023

Metal Catalysts for the Electrochemical Reduction of CO2

Cedric David Koolen

The world by and large has adopted the The Paris Agreement, which commits any signing party to cut greenhouse emissions drastically and prevent global heating above 2 °C beyond pre-industrial levels. For this ambitious goal to be met, ratifying states need ...

EPFL2023

Shear strength and shear stiffness analysis of compacted Wyoming-type bentonite

Alessio Ferrari

Wyoming-type bentonite is one of the materials to be used as part of the Engineered Barrier System (EBS) in deep geological disposal facilities for the safe disposal of spent nuclear fuel.In the KBS-3 type repository, the canisters containing the spent fue ...

ELSEVIER2023

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

Delayed Hydride Cracking in Irradiated and Unirradiated Zircaloy-2 Cladding

Aaron William Colldeweih

Zirconium alloys used in the nuclear industry are exposed to extreme conditions undergoing high levels of irradiation damage and corrosion. Zircaloy-2 is used as nuclear fuel cladding in boiling water reactors and for the encapsulation of the spallation ta ...

EPFL2022

Multi-physics modeling of VVERs with high fidelity high-resolution codes

Marianna Papadionysiou

The calculations performed for the design and operation of a Nuclear Power Plant (NPP) are a key factor for their safety analyses. The standard for the computational analysis of NPPs is the so called conventional approach, which relies on coarse mesh diffu ...

EPFL2022

Data-Driven Predictive Models: Calculational Bias in Characterization of Spent Nuclear Fuel

Characteristics of the spent nuclear fuel (SNF) are typically calculated, requiring validation a priori. The validation process relies on the difference between calculations and measurements, namely the bias. Usually, predicting the bias based on benchmark ...

EPFL2022

Validation of spent nuclear fuel decay heat calculations using Polaris, ORIGEN and CASMO5

Stefano Caruso, Andreas Pautz, Dimitri Rochman

Decay heat calculations of spent nuclear fuel (SNF) using Polaris and ORIGEN codes in the SCALE code sys-tem, and CASMO5 code, are validated using measurements from the Clab and GE-Morris facilities. Multiple hypothesis testing, relying on permutations and ...

PERGAMON-ELSEVIER SCIENCE LTD2022