Combination of micro-macro and spatially hybrid fluid-kinetic approach for hydrogenic plasma edge neutrals

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Journal Title
Journal ISSN
Volume Title
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
Date
2022-06
Major/Subject
Mcode
Degree programme
Language
en
Pages
13
Series
Contributions to Plasma Physics, articlenumber 202100188
Abstract
A new hybrid fluid-kinetic approach for the hydrogenic neutrals (atoms and molecules) in the plasma edge is presented. The hybrid approach combines a fully kinetic model for the atoms in the low-collisional regions near the vessel wall, and for the molecules in the whole plasma edge domain, with a micro-macro approach for atoms originating from recycling at the divertor targets, volumetric recombination, and dissociation of molecules. With the micro-macro approach, the originally scattering-dominated collision term due to charge-exchange collisions in the kinetic equation is transformed to an absorption-dominated term, while a large part of the neutral population is treated through a fluid approach. For JET L-mode plasmas, the premature termination of Monte Carlo particle trajectories in the hybrid approach leads to a reduction of the CPU time by approximately a factor 3 for a high-recycling case and by approximately a factor 11 for a partially detached case compared with a simulation with fully kinetic neutrals and the same amount of particles. For coupled fluid plasma - hybrid neutral simulations - the hybrid approach predicts the plasma divertor target profiles with a maximum hybrid-kinetic discrepancy of approximately 30%.
Description
| openaire: EC/H2020/633053/EU//EUROfusion
Keywords
fluid approximation, kinetic model, neutrals, plasma edge modelling, SOLPS-ITER, MODEL, IMPLEMENTATION, SIMULATIONS, TRANSPORT
Other note
Citation
Horsten , N , Groth , M , Dekeyser , W , Van Uytven , W , Carli , S & JET Contributors 2022 , ' Combination of micro-macro and spatially hybrid fluid-kinetic approach for hydrogenic plasma edge neutrals ' , Contributions to Plasma Physics , vol. 62 , no. 5-6 , 202100188 . https://doi.org/10.1002/ctpp.202100188