Publications associées à Interface Tracking Investigation of the Sliding Bubbles Effects on Heat Transfer in the Laminar Regime

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

Gamma-ray Spectroscopy in Low-Power Nuclear Research Reactors

Andreas Pautz, Oskari Ville Pakari, Vincent Pierre Lamirand

Gamma-ray spectroscopy is an effective technique for radioactive material characterization, routine inventory verification, nuclear safeguards, health physics, and source search scenarios. Gamma-ray spectrometers typically cannot be operated in the immedia ...

MDPI2024

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

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

Demonstration of a sparse sensor placement technique to the limited diagnostic set in a fusion power plant

Lorenzo Martinelli, Artur Perek

DEMO will have a limited diagnostic set for optimization of reactor performance, and limited diagnostic coverage due to challenging reactor conditions. This poses challenges for control, especially for detachment control which is planned to be performed wi ...

Elsevier Science Sa2024

Heterogeneous catalysis via light-heat dual activation: A path to the breakthrough in C1 chemistry

Bingqiao Xie

A hybrid photothermal catalytic system, which combines both the photochemical (light) and thermal (heat) activation pathways over a bifunctional catalyst, has demonstrated remarkable levels of reaction activity and selectivity when compared with individual ...

Cell Press2024

Noise-induced transitions past the onset of a steady symmetry-breaking bifurcation: The case of the sudden expansion

François Gallaire, Edouard Boujo, Yves-Marie François Ducimetière

We consider fluid flows, governed by the Navier-Stokes equations, subject to a steady symmetry-breaking bifurcation and forced by a weak noise acting on a slow timescale. By generalizing the multiple-scale weakly nonlinear expansion technique employed in t ...

2024

Turbulence and Heat exchange in the Near-Surface Boundary Layer over Patchy Snow

Michael Haugeneder

The atmospheric layer adjacent to the earth's surface is of crucial importance for weather models due to the exchange of energy between the surface and the atmosphere. This exchange is dependent on the various surface properties and influences the state of ...

EPFL2024

The Advection Boundary Law in presence of mean-flow and spinning modes

In the attempt to reduce fuel consumption, a new generation of Ultra-High-By-Pass-Ratio (UHBR) turbofans have been introduced in the aeronautic industry which are structurally noisier especially at lower frequencies, because of their larger diameter, lower ...

SPIE2024

Turbulence in the Strongly Heterogeneous Near-Surface Boundary Layer over Patchy Snow

Michael Lehning, Dylan Stewart Reynolds, Michael Haugeneder

The near-surface boundary layer above patchy snow cover in mountainous terrain is characterized by a highly complex interplay of various flows on multiple scales. In this study, we present data from a comprehensive field campaign that cover a period of 21 ...

2024

Computational fluid dynamics simulations of the heat transfer properties of graphene-based nanolubricants and application to hydrodynamic lubrication

Roberto Guarino

In this paper, we consider experimental data available for graphene-based nanolubricants to evaluate their convective heat transfer performance by means of computational fluid dynamics (CFD) simulations. Single-phase models with temperature-dependent prope ...

Aip Publishing2024

Nonlinear simulation of plasma turbulence using a gyrokinetic moment-based approach

Antoine Cyril David Hoffmann

Plasma turbulence plays a fundamental role in determining the performances of magnetic confinement fusion devices, such as tokamaks. Advances in computer science, combined with the development of efficient physical models, have significantly improved our u ...

EPFL2024

The effect of pressure-anisotropy-driven kinetic instabilities on magnetic field amplification in galaxy clusters

Yoan Rappaz, Jennifer Waltraud Schober

Context. The intracluster medium (ICM) is the low-density diffuse gas that fills the space between galaxies within galaxy clusters. It is primarily composed of magnetized plasma, which reaches virial temperatures of up to 10(8) K, probably due to mergers o ...

Edp Sciences S A2024

Extension, validation, and optimization of Serpent/DYN3D/ATHLET code system for SFR applications

Vincenzo Anthony Di Nora

The sequence of codes Serpent/DYN3D has been developed by the Helmholtz-Zentrum Dresden-Rossendorf and successfully applied to core static and transient analyses of sodium-cooled fast reactors (SFRs). The successful application of the sequence to SFRs was ...

EPFL2023

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

Three-dimensional micro-CT images of UV-frozen flow fronts recorded at different flow regimes

Véronique Michaud, Jacobus Gerardus Rudolph Staal

Segmented micro-CT images of flow fronts produced by UV-flow freezing. Front morphologies correspond to capilary-dominated, equilibrated and viscous-dominated flow regimes. ...

Zenodo2023

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

Integrated modelling of neon impact on JET H-mode core plasmas

Yann Camenen, Michele Marin

Nuclear fusion reactor plasmas will need to exhaust a significant proportion of energy flux through radiative processes, to enable acceptable divertor loads. This can be obtained by line radiation from impurities, injected from the plasma edge. There are h ...

IOP Publishing Ltd2023

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

Measurement and modelling of dynamic fluid saturation in carbon reinforcements

Véronique Michaud, Baris Çaglar, Helena Luisa Teixido Pedarros, Guillaume Clément Broggi

We propose a methodology to monitor the progressive saturation of a non-translucent unidirectional carbon fabric stack through its thickness by means of X-ray radiography and extract the dynamic saturation curves using image analysis. Four constant flow ra ...

2023