Integration of kinetic ions in a three‐dimensional Monte‐Carlo neutral transport code

Abstract

Charged particles of species different from the major constituents of a plasma might not reach local thermodynamic equilibrium during their lifespan. Such low collisional ions render the often‐used fluid description, assuming Maxwellian velocity distribution, as insufficient. Hence, kinetic treatment of such minorities becomes inevitable. The three‐dimensional kinetic neutral particle Monte‐Carlo code EIRENE [D. Reiter et al., Fusion Science and Technology, 47 (2), 172 (2005)] possesses a model for ion transport reduced in physics, consisting of field‐line tracing and energy relaxation of particles. The trajectory integration is now extended to account for first‐order particle drifts, anomalous cross‐field diffusion denoting for turbulence effects, and the consideration of the magnetic mirror force. The technical implementation, as well as the verification of the enhanced kinetic ion transport is being reported.

Effects of toroidal plasma current on divertor power depositions on Wendelstein 7-X

“…The simulation presented here uses only an isotropic diffusion coefficient D ⊥ , while in reality particle drifts add convection patterns to the edge transport, such that the second leg of the island can get more loads. An upgraded version of the comprehensive edge simulation code EMC3-EIRENE [33,34] is foreseen to incorporate drifts to quantitatively understand this effect in the future [35].…”

Fluid, kinetic and hybrid approaches for neutral and trace ion edge transport modelling in fusion devices

“…The alternative perspective APMC approach is also considered [23], including development and first tests of the newly proposed KDMC formulation with a multilevel option (ML) [35] aimed to overcome the bias. In addition, the option to track ions kinetically is improved [36]. The advantages of hybridisation methods are compared based on experience from the first applications to test cases relevant for fusion devices.…”

“…In fact, treating ions on the kinetic side of CFD-EIRENE packages in addition to a fluid/hybrid approximation for neutrals provides more flexible and seamless coupling between the codes as well as an internal benchmarking mechanism. In the last two years fundamental physical enhancements of the kinetic ion transport part of EIRENE were performed [36], by adding first-order drift effects, cross-field diffusion, and magnetic mirror force. These additions, which are relevant for thoroughly investigating the full three-dimensional influence of impurities on actual fusion devices, have been cross-checked on simple model cases against analytical properties of passing and trapped (banana) particle orbits, as well as checking on the introduction of numerical diffusion by our integration scheme.…”