Integrated divertor modelling of impurity transport in detached plasma

Shimizu, Katsuhiro; Takizuka, Tomonori; Oya, Kaoru*; Inai, Kensuke*; Nakano, Tomohide; Takayama, Arimichi*; Kawashima, Hisato; Hoshino, Kazuo

An integrated divertor simulation code SONIC has been developed. The self-consistent coupling of a Monte Carlo (MC) impurity code IMPMC to a divertor code SOLDOR/NEUT2D is succeeded by overcoming the intrinsic problems of MC modelling for impurity transport. MC modelling for impurity transport is required in order to take into account the kinetic effect and the complex dissociation processes of hydrocarbons. The dynamic evolution of X-point MARFE observed in JT-60U is investigated. The simulation results indicate that the hydrocarbons sputtered from the dome contribute to the enhanced radiation near the X-point. Without the recycling, the kinetic effect of the thermal force improves the helium compression, compared with the conventional (fluid) evaluation. This effect is, however, masked by the recycling at the divertor targets.