Search

Your search keyword '"Serre, E."' showing total 379 results
Start Over Author "Serre, E."
379 results on '"Serre, E."'

1. Turbulent relaxation patterns in SOL plasma

Author

Varennes, R, Dif-Pradalier, G, Ghendrih, P, Grandgirard, V, Panico, O, Sarazin, Y, Serre, E, and Zarzoso, D

Subjects
Physics - Plasma Physics
Abstract

Relaxations of localized over-density in a plane transverse to the magnetic field are numericallyinvestigated under the effect of drift-wave and interchange drives in SOL conditions. Such a controlleddeparture from thermodynamic equilibrium allows the investigation of fundamental processesat play in cross-field transport. Interchange instabilities generate ballistic outward radial flux withlow amplitude zonal flow patterns, whereas drift-wave instabilities result in symmetric radial fluxwith large amplitude zonal flow patterns. When both instabilities are considered, the combinedeffects tend to favor drift-waves, leading to a weaker outward flux with larger zonal flow patterns.

Published
2024

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

Author

Oliveira, D. S., Body, T., Galassi, D., Theiler, C., Laribi, E., Tamain, P., Stegmeir, A., Giacomin, M., Zholobenko, W., Ricci, P., Bufferand, H., Boedo, J. A., Ciraolo, G., Colandrea, C., Coster, D., de Oliveira, H., Fourestey, G., Gorno, S., Imbeaux, F., Jenko, F., Naulin, V., Offeddu, N., Reimerdes, H., Serre, E., Tsui, C. K., Varini, N., Vianello, N., Wiesenberger, M., Wüthrich, C., and Team, the TCV

Subjects
Physics - Plasma Physics
Abstract

Self-consistent full-size turbulent-transport simulations of the divertor and SOL of existing tokamaks have recently become feasible. This enables the direct comparison of turbulence simulations against experimental measurements. In this work, we perform a series of diverted Ohmic L-mode discharges on the TCV tokamak, building a first-of-a-kind dataset for the validation of edge turbulence models. This dataset, referred to as TCV-X21, contains measurements from 5 diagnostic systems -- giving a total of 45 1- and 2-D comparison observables in two toroidal magnetic field directions. The dataset is used to validate three flux-driven 3D fluid-turbulence models: GBS, GRILLIX and TOKAM3X. With each model, we perform simulations of the TCV-X21 scenario, tuning the particle and power source rates to achieve a reasonable match of the upstream separatrix value of density and electron temperature. We find that the simulations match the experimental profiles for most observables at the OMP -- both in terms of profile shape and absolute magnitude -- while a poorer agreement is found towards the divertor targets. The match between simulation and experiment is seen to be sensitive to the value of the resistivity, the heat conductivities, the power injection rate and the choice of sheath boundary conditions. Additionally, despite targeting a sheath-limited regime, the discrepancy between simulations and experiment also suggests that the neutral dynamics should be included. The results of this validation show that turbulence models are able to perform simulations of existing devices and achieve reasonable agreement with experimental measurements. Where disagreement is found, the validation helps to identify how the models can be improved. By publicly releasing the experimental dataset, this work should help to guide and accelerate the development of predictive turbulence simulations of the edge and SOL.

Published
2021
Full Text
View/download PDF

6. Implementation of a discrete Immersed Boundary Method in OpenFOAM

Author

Constant, E., Li, C., Favier, J., Meldi, M., Meliga, P., and Serre, E.

Subjects
Physics - Fluid Dynamics
Abstract

In this paper, the Immersed Boundary Method (IBM) proposed by Pinelli is implemented for finite volume approximations of incompressible Navier-Stokes equations solutions in the open source toolbox OpenFOAM version 2.2. Solid obstacles are described using a discrete forcing approach for boundary conditions. Unlike traditional approaches encompassing the presence of a solid body using conformal meshes and imposing no-slip boundary conditions on the boundary faces of the mesh, the solid body is here represented on the Eulerian Cartesian mesh through an ad-hoc body force evaluated on a set of Lagrangian markers. The markers can move across the Eulerian mesh, hence allowing for a straightforward analysis of motion or deformation of the body. The IBM method is described and implemented in PisoFOAM, whose Pressure-Implicit Split-Operator (PISO) solver is modified accordingly. The presence of the solid body and the divergence-free of the fluid velocity are imposed simultaneously by sub-iterating between IBM and the pressure correction step. This scheme allows for the use of fast optimized Poisson solvers while granting excellent accuracy with respect to the previously mentioned constraints. Various 2D and 3D well-documented test cases of flows around fixed or moving circular cylinders are simulated and carefully validated against existing data from the literature. The capability of the new solver is discussed in terms of accuracy and numerical performances.

Published
2016

7. Global particle buildup simulations with gas puff scan: application to WEST discharge.

Author

Kudashev, I., d'Abusco, M. Scotto, Glasser, A., Serre, E., Schwander, F., Bufferand, H., Ciraolo, G., Ghendrih, P., Tamain, P., Thrysøe, Alexander Simon, and Salmi, Antti

Subjects
CHARGE exchange, CONFIGURATIONS (Geometry), PHENOMENOLOGICAL theory (Physics), PRESSURE drop (Fluid dynamics), PARTICLE interactions, FUSION reactor divertors, FUSION reactors
Abstract

This paper deals with the distribution of sources, transport, and exhaust of particles in a tokamak. Knowledge and understanding of all the physical phenomena involved in the global particle buildup are necessary to study and predict density regimes and subsequently to develop optimized scenarios for tokamak operation in order to control heat and particle exhaust. Neutral particles and their interactions with plasma are central in this perspective. This paper discusses the impact of varying the intensity of particle fueling in 2D transport simulations of a WEST discharge. Simulations are performed with an updated version of SOLEDGE-HDG that allows a more realistic transport of neutrals using a self-consistent diffusive model based on charge exchange and ionization processes. New code capabilities allow the entire WEST poloidal cross section to be simulated in a realistic configuration for both geometry and the range of control parameters. A gas puff scan illustrates the main features of the sheath-limited, high-recycling, and detached regimes, such as the buildup of the temperature gradient and the pressure drop in the scrape-off layer (SOL), the target temperature falling to 1 eV, and the ionization source moving away from the targets, as well as the particle flux rollover. A crude estimate of wall erosion is also provided, showing the respective role of each plasma wall component in each of these regimes. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

19. Model validation of tungsten erosion and redeposition properties using biased tungsten samples on DiMES

Author

Cappelli, L., primary, Guterl, J., additional, Fedorczak, N., additional, Rudakov, D.L., additional, Sinclair, G., additional, Abrams, T., additional, Di Genova, S., additional, Losada, U., additional, Bykov, I., additional, Popović, Ž., additional, Truong, D., additional, Watkins, J., additional, Wilcox, R.S., additional, Wampler, W.R., additional, and Serre, E., additional

Published
2023
Full Text
View/download PDF

42. Asymptotic behaviour, non-local dynamics and data assimilation tailoring of the reduced κ − ε model to address turbulent transport of fusion plasmas

Author

Auroux, D, Ghendrih, P, Lamerand, L, Rapetti, F, Serre, E, Laboratoire Jean Alexandre Dieudonné (LJAD), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Control, Analysis and Simulations for TOkamak Research (CASTOR), Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire Jean Alexandre Dieudonné (LJAD), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), Institut de Recherche sur la Fusion par confinement Magnétique (IRFM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire de Mécanique, Modélisation et Procédés Propres (M2P2), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), ANR-19-CE46-0005,SISTEM,Simulations par schémas d'ordre élevé du transport et de la turbulence dans un tokamak(2019), European Project: 101052200,Implementation of activities described in the Roadmap to Fusion during Horizon Europe through a joint programme of the members of the EUROfusion consortium,EUROfusion, Serre, Eric, Simulations par schémas d'ordre élevé du transport et de la turbulence dans un tokamak - - SISTEM2019 - ANR-19-CE46-0005 - AAPG2019 - VALID, and EUROfusion - EUROfusion - - Implementation of activities described in the Roadmap to Fusion during Horizon Europe through a joint programme of the members of the EUROfusion consortium0000-00-00 - 0000-00-00 - 101052200 - VALID

Subjects
[PHYS]Physics [physics], [SPI]Engineering Sciences [physics], [SPI] Engineering Sciences [physics], [SPI.FLUID]Engineering Sciences [physics]/Reactive fluid environment, [SPI.PLASMA]Engineering Sciences [physics]/Plasmas, [SPI.PLASMA] Engineering Sciences [physics]/Plasmas, [INFO.INFO-MO] Computer Science [cs]/Modeling and Simulation, [SPI.FLUID] Engineering Sciences [physics]/Reactive fluid environment, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, [PHYS] Physics [physics]
Abstract

International audience; The high-dimensional and multiscale nature of fusion plasma flows require the development of reduced models to be implemented in numerical codes capable of capturing the main features of turbulent transport in a sufficiently short time to be useful during tokamak operation. This paper goes further in the analysis of the dynamics of the κ − ε model based on the turbulent kinetic energy κ and its dissipation rate ε [Baschetti et al., Nuc. Fus 61, 106020 (2021)] to improve the predictability of the transverse turbulent transport in simulation codes. Present 1D results show further capabilities with respect to current models (based on constant effective perpendicular diffusion) and on the standard quasi-linear approach. The nonlinear dependence of D in κ and ε estimated from two additional transport equations allow to introduce some non-locality in the transport model. This is illustrated by the existence of parameter ranges with turbulence spreading. The paper also addresses another issue related to the uncertainties on the inherent free parameters of such reduced model. The study proposes a new approach in the fusion community based on a variational data assimilation involving the minimisation of a cost function defined as the distance between the reference data and the calculated values. The results are good, and show the ability of the data assimilation to reduce uncertainties on the free parameters, which remains a critical point to ensure the total reliability of such an approach.

Published
2022

48. High Performance Computer Codes and their Application to Optimize Crystal Growth Processes, III

Author

Czarny, O., Droll, P., El Ganaoui, M., Fischer, B., Hainke, M., Kadinski, L., Kaufmann, P., Krastev, K., Mešgić, E., Metzger, M., Raspo, I., Serre, E., Bontoux, P., Durst, E., Müller, G., Schäfer, M., Hirschel, E. H., editor, Fujii, K., editor, Haase, W., editor, van Leer, B., editor, Leschziner, M. A., editor, Pandolfi, M., editor, Periaux, J., editor, Rizzi, A., editor, Roux, B., editor, and Hirschel, Ernst Heinrich, editor

Published
2003
Full Text
View/download PDF

50. High Performance Computer Codes and their Application to Optimize Crystal Growth Processes, II

Author

Degenhardt, A., Droll, P., El Ganaoui, M., Kadinski, L., Kurz, M., Lamazouade, A., Morvan, D., Raspo, I., Serre, E., Bontoux, P., Durst, F., Müller, G., Schäfer, M., Hirschel, Ernst Heinrich, editor, Fujii, Kozo, editor, Haase, Werner, editor, van Leer, Bram, editor, Leschziner, Michael A., editor, Pandolfi, Maurizio, editor, Periaux, Jaques, editor, Rizzi, Arthur, editor, and Roux, Bernard, editor

Published
2001
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results