English
Related papers

Related papers: Validity of models for Dreicer generation of runaw…

200 papers

Integrated modelling of electron runaway requires computationally expensive kinetic models that are self-consistently coupled to the evolution of the background plasma parameters. The computational expense can be reduced by using…

Plasma Physics · Physics 2020-01-27 L Hesslow , L Unnerfelt , O Vallhagen , O Embreus , M Hoppe , G Papp , T Fülöp

When simulating runaway electron dynamics in tokamak disruptions, fluid models with lower numerical cost are often preferred to more accurate kinetic models. The aim of this work is to compare fluid and kinetic simulations of a large…

Relativistic runaway electrons are a major concern in tokamaks. The European framework for Integrated Modelling (EU-IM), facilitates the integration of different plasma simulation tools by providing a standard data structure for…

For the simulation of disruptions in tokamak fusion plasmas, a fluid model describing the evolution of relativistic runaway electrons and their interaction with the background plasma is presented. The overall aim of the model is to…

Plasma Physics · Physics 2019-07-01 V. Bandaru , M. Hoelzl , F. J. Artola , G. Papp , G. T. A. Huijsmans

Tokamak start-up is characterized by low electron densities and strong electric fields, in order to quickly raise the plasma current and temperature, allowing the plasma to fully ionize and magnetic flux surfaces to form. Such conditions…

Plasma Physics · Physics 2022-06-30 M. Hoppe , I. Ekmark , E. Berger , T. Fülöp

Accurate modeling of runaway electron generation and losses during tokamak disruptions is crucial for the development of reactor-scale tokamak devices. In this paper we present a reduced model for runaway electron losses due to flux surface…

Plasma Physics · Physics 2024-10-07 Oskar Vallhagen , Lise Hanebring , Tünde Fülöp , Mathias Hoppe , Istvan Pusztai

Improved understanding of runaway-electron formation and decay processes are of prime interest for the safe operation of large tokamaks, and the dynamics of the runaway electrons during dynamical scenarios such as disruptions are of…

Plasma Physics · Physics 2016-09-15 A. Stahl , O. Embréus , G. Papp , M. Landreman , T. Fülöp

Avoidance of the harmful effects of runaway electrons (REs) in plasma-terminating disruptions is pivotal in the design of safety systems for magnetic fusion devices. Here, we describe a computationally efficient numerical tool, that allows…

Plasma Physics · Physics 2021-08-11 M. Hoppe , O. Embreus , T. Fülöp

$\textit{Tokamak disruptions}$ can give rise to the $\textit{runaway phenomenon}$, which is typical in plasma physics and describes the almost unbound acceleration of electrons to relativistic velocities and can lead to the formation of a…

Plasma Physics · Physics 2023-09-21 Benjamin Buchholz

Dreicer generation is one of the main mechanisms of runaway electrons generation, in particular during tokamak startup. In fully ionized plasma it is described as a diffusive flow from the Maxwellian core into high energies under the effect…

Plasma Physics · Physics 2024-04-25 Y. Lee , P. Aleynikov , P. C. de Vries , H. -T. Kim , J. Lee , M. Hoppe , J. -K. Park , G. J. Choi , J. Gwak , Y. -S. Na

Mitigation of runaway electrons is one of the outstanding issues for the reliable operation of ITER and other large tokamaks, and accurate estimates for the expected runaway-electron energies and current are needed. Previously, linearized…

Plasma Physics · Physics 2016-12-21 A. Stahl , O. Embréus , M. Landreman , G. Papp , T. Fülöp

A disrupting plasma in a high-performance tokamak such as ITER or SPARC may generate large runaway electron currents that, upon impact with the tokamak wall, can cause serious damage to the device. To quickly identify regions of safe…

Plasma Physics · Physics 2026-03-24 Björn Zaar , István Pusztai , Ida Ekmark , Tünde Fülöp

The disruption and runaway electron analysis model code was extended to include tungsten impurities in disruption simulations with the aim of studying the runaway electron (RE) generation. This study investigates RE current sensitivity on…

A new fluid model for runaway electron simulation based on fluid description is introduced and implemented in the magnetohydrodynamics code M3D-C1, which includes self-consistent interactions between plasma and runaway electrons. The model…

In cold weakly-ionized plasmas, Dreicer generation mechanism can be non-diffusive as demonstrated in [Y. Lee et. al. Phys. Rev. Lett. 133 17 175102 (2024)]. By expanding the previous letter, we present the detailed description of a proper…

Plasma Physics · Physics 2025-09-04 Yeongsun Lee , Pavel Aleynikov , Peter de Vries , Jong-Kyu Park , Yong-Su Na

Runaway electrons (REs) can be generated in tokamak plasmas if the accelerating force from the toroidal electric field exceeds the collisional drag force due to Coulomb collisions with the background plasma. In ITER, disruptions are…

Plasma Physics · Physics 2015-03-23 E. Nilsson , J. Decker , Y. Peysson , R. S. Granetz , F. Saint-Laurent , M. Vlainic

The safe operation of tokamak reactors requires a reliable modeling capability of disruptions, and in particular the spatio-temporal dynamics of associated runaway electron currents. In a disruption, instabilities can break up magnetic…

Plasma Physics · Physics 2022-09-14 István Pusztai , Mathias Hoppe , Oskar Vallhagen

Understanding generation and mitigation of runaway electrons in disruptions is important for the safe operation of future tokamaks. In this paper we investigate runaway dynamics in reactor-scale spherical tokamaks. We study both the…

Plasma Physics · Physics 2023-01-04 E. Berger , I. Pusztai , S. L. Newton , M. Hoppe , O. Vallhagen , A. Fil , T. Fülöp

Plasma current instabilities can destabilize the plasma discharge and cool the plasma rapidly. In such $\textit{disruptions}$ or in the start-up phase of the reactor, inductive electric fields are generated which accelerate electrons to…

Plasma Physics · Physics 2024-10-30 Benjamin Buchholz

Runaway electron loads onto material structures are a major concern for future large tokamaks due to the efficient avalanching at high plasma currents. Here, we perform predictive studies using the JOREK code for a plausible plasma…

‹ Prev 1 2 3 10 Next ›