Publications associées à A comparison between a refined two-point model for the limited tokamak SOL and self-consistent plasma turbulence simulations

Mean-field transport equations and energy theorem for plasma edge turbulent transport

This paper establishes a mean-field equation set and an energy theorem to provide a theoretical basis in view of the development of self-consistent, physics-based turbulent transport models for mean-field transport codes. A rigorous averaging procedure ide ...

Cambridge University Press2024

Validation of GBS plasma turbulence simulation of the TJ-K stellarator

Joaquim Loizu Cisquella, Paolo Ricci

We present a validation of a three-dimensional, two-fluid simulation of plasma turbulence in the TJ-K stellarator, a low temperature plasma experiment ideally suited for turbulence measurements. The simulation is carried out by the GBS code, recently adapt ...

IOP Publishing Ltd2023

Many-body physics with strongly interacting fermions coupled to light

Victor Youri Helson

This thesis reports on the realization of the first experiments conducted with superfluid, strongly interacting Fermi gases of 6Li coupled to the light field of an optical cavity. In the scope of existing ultracold atomic platforms, this is the first time ...

EPFL2023

Laterally unconfined neutral or negative buoyancy inflow into a quiescent ambient over sloping bottom

Haoran Shi

This work studies the nearshore hydrodynamics of a shallow turbulent flow entering a laterally unconfined quiescent ambient with a sloping bottom boundary. Examples of such flow are neutrally buoyant ebb tidal jets and hyperpycnal river plumes entering ope ...

EPFL2023

Cavity Quantum Electrodynamics with strongly correlated fermions

Kevin Etienne Robert Roux

This thesis presents the first cavity quantum electrodynamics experiments performed with a degenerate gas of

^6

Li with strong atom-atom interactions. The first part of this manuscript describes the design and the building of the apparatus that has been e ...

EPFL2022

Numerical simulations of gas puff imaging using a multi-component model of the neutral-plasma interaction in the tokamak boundary

Paolo Ricci

A three-dimensional simulation of gas puff imaging (GPI) diagnostics is carried out by using a self-consistent multi-component model of the neutral-plasma interaction. The simulation, based on the drift-reduced Braginskii model for the plasma and a kinetic ...

AIP Publishing2022

A self-consistent multi-component model of plasma turbulence and kinetic neutral dynamics for the simulation of the tokamak boundary

Paolo Ricci

A self-consistent model is presented for the simulation of a multi-component plasma in the tokamak boundary. A deuterium plasma is considered, with the plasma species that include electrons, deuterium atomic ions and deuterium molecular ions, while the deu ...

IOP Publishing Ltd2022

Validation of edge turbulence codes against the TCV-X21 diverted L-mode reference case

Holger Reimerdes, Paolo Ricci, Christian Gabriel Theiler, Hugo De Oliveira, Eric Serre, Cedric Kar-Wai Tsui, Nicola Vianello, Nicola Offeddu, Maurizio Giacomin, Davide Galassi, Sophie Danielle Angelica Gorno, Claudia Colandrea

Self-consistent full-size turbulent-transport simulations of the divertor and scrape-off-layer (SOL) of existing tokamaks have recently become feasible. This enables the direct comparison of turbulence simulations against experimental measurements. In this ...

IOP Publishing Ltd2022

The Forward Physics Facility at the High-Luminosity LHC

Martin Bauer, Alexey Boyarsky, Enrico Bertuzzo, Lesya Shchutska, Wenjing Wu, Karan Kumar, Francesco Cerutti, Wei Liu, Patrick Foldenauer, Yi Zhang, Saurabh Nangia, Raffaele Tito D'Agnolo, Emanuele Copello, Ji Hyun Kim, Yiming Li, Zheng Wang, Jing Li

High energy collisions at the High-Luminosity Large Hadron Collider (LHC) produce a large number of particles along the beam collision axis, outside of the acceptance of existing LHC experiments. The proposed Forward Physics Facility (FPF), to be located s ...

2023

A physics-based model for wind turbine wake expansion in the atmospheric boundary layer

Fernando Porté Agel, Dara Vahidi

Analytical wind turbine wake models are widely used to predict the wake velocity deficit. In these models, the wake growth rate is a key parameter specified mainly with empirical formulations. In this study, a new physics-based model is proposed and valida ...

Cambridge University Press2022

Efficient Semiclassical Evaluation of Electronic Coherences in Polyatomic Molecules

Jiri Vanicek, Nikolay Golubev

Exposing a molecule to an intense light pulse can create a nonstationary quantum state, thus launching correlated dynamics of electrons and nuclei. Although much had been achieved in the understanding of fundamental physics behind the electron-nuclear inte ...

SWISS CHEMICAL SOC2022

Catalyzing Bond-Dissociation in Graphene via Alkali-Iodide Molecules

Klaus Kern, Stephan Rauschenbach, Sabine Abb, Sven Alexander Szilagyi, Hannah Julia Ochner

Atomic design of a 2D-material such as graphene can be substantially influenced by etching, deliberately induced in a transmission electron microscope. It is achieved primarily by overcoming the threshold energy for defect formation by controlling the kine ...

WILEY-V C H VERLAG GMBH2021

Eliminating turbulent self-interaction through the parallel boundary condition in local gyrokinetic simulations

Stephan Brunner, Ajay Chandrarajan Jayalekshmi, Justin Richard Ball

In this work, we highlight an issue that may reduce the accuracy of many local nonlinear gyrokinetic simulations – turbulent self-interaction through the parallel boundary condition. Given a sufficiently long parallel correlation length, individual turbule ...

Cambridge University Press2020

Generation of chiral asymmetry via helical magnetic fields

Ruth Durrer, Jennifer Waltraud Schober

It is well known that helical magnetic fields undergo a so-called inverse cascade by which their correlation length grows due to the conservation of magnetic helicity in classical ideal magnetohydro-dynamics (MHD). At high energies above approximately 10 M ...

American Physical Society2020

Invariant solutions underlying small- and large-scale structures in turbulent boundary layers

Sajjad Azimi

Flows of gases and liquids interacting with solid objects are often turbulent within a thin boundary layer. As energy dissipation and momentum transfer are dominated by the boundary layer dynamics, many engineering applications can benefit from an improved ...

EPFL2020

Large eddy simulation of the tip-leakage cavitating flow with an insight on how cavitation influences vorticity and turbulence

Mohamed Farhat, Huaiyu Cheng

Cavitation within a tip leakage flow remains a challenging issue in a variety of axial hydraulic machines. It is still not possible nowadays to predict cavitation occurrence in such a flow with acceptable accuracy. In the present study, we have carried out ...

ELSEVIER SCIENCE INC2020

Dynamics of nanoscale systems probed by time-resolved STM-induced luminescence

Anna Maria Roslawska

The efficiency and peculiarities of processes such as surface adsorption or electron-to-photon energy conversion in organic and inorganic structures are determined by the dynamics at the scale of individual molecules, atoms and charges. The timescales of s ...

EPFL2019

Impact of neutral density fluctuations on gas puff imaging diagnostics

Paolo Ricci, Christoph Wersal

A three-dimensional turbulence simulation of the SOL and edge regions of a toroidally limited tokamak is carried out. The simulation couples self-consistently the drift-reduced two-fluid Braginskii equations to a kinetic equation for neutral atoms. A diagn ...

International Atomic Energy Agency2017

Neutral atom dynamics and plasma turbulence in the tokamak periphery

Christoph Wersal

Understanding the physical mechanisms at play in the interaction between turbulent plasma and neutral particles is a crucial issue that we approach in this Thesis by using a first-principles self-consistent model of the tokamak periphery implemented in the ...

EPFL2017

The GBS code for tokamak scrape-off layer simulations

Trach-Minh Tran, Sébastien Jolliet, Joaquim Loizu Cisquella, Paolo Ricci, Fabio Riva, Annamaria Mosetto, Federico David Halpern, Christoph Wersal

We describe a new version of GBS, a 3D global, flux-driven plasma turbulence code to simulate the turbulent dynamics in the tokamak scrape-off layer (SOL), superseding the code presented by Ricci et al. (2012) [14]. The present work is driven by the object ...

Elsevier2016