3D analysis of impurity transport and radiation for ITER limiter start-up configurations

Abstract

Previous three-dimensional modelling of the ITER SOL plasma transport during the current ramp-up limiter phase with the EMC3-EIRENE code [1] has been extended to include the limiter-released Beryllium (Be) production, transport and radiation. The 3D density distributions of the single Be charge states and related line radiation have been simulated for two plasma densities and three plasma configurations during the ramp-up phase [2]. The transport coefficients were also varied to check the sensitivity of the radiation to the transport. As expected, for all three configurations the radiated fraction of the SOL input power, P rad /P SOL , increases with the density at the last closed flux surface (LCFS). Preliminary results indicate largest P rad /P SOL for the 4.5 MA configuration, high density, high diffusivity case, P rad /P SOL ≈19%, Be concentration ≈ 16 % and Z eff ≈ 2.5 at the LCFS. These absolute numbers scale linearly with the assumed sputtering coefficients, but are rather insensitive to the initial energy of the sputtered Be atoms.

Comparison between stellarator and tokamak divertor transport

“…EIRENE is a 3D kinetic Monte Carlo Code for neutral particles, radiation transfer and kinetic trace ion impurity transport [23]. EMC3-EIRENE was initially developed and applied for W7-AS [22,[25][26][27][28][29] and has recently found applications in 3D edge transport problems encountered not only in stellarators [30,31] but also in tokamaks [32][33][34][35][36][37]. This paper compares the essential divertor transport features of axisymmetric and helical devices.…”

Monte-Carlo fluid approaches to detached plasmas in non-axisymmetric divertor configurations

“…Thanks to its high geometric flexibility as well as its 3D capability, the EMC3-Eirene has been applied to a wide variety of magnetic confinement fusion devices including stellarators [25][26][27][28][29][30], tokamaks [31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47] and linear devices [48,49], bridging different divertor concepts.…”

Implicit coupling of impurity transport at the SOL–core interface

“…In fact, the work presented is this paper was initially triggered by an ITER application of the EMC3-Eirene code for studying beryllium radiation during the plasma start-up phase with two local limiters [3], and further motivated by a tungsten transport study for ASDEX Upgrade [4]. Independently of the SOL thickness, the SOL temperatures are usually too low to fully ionize the impurities.…”