A significant reduction of 70% in tungsten (W) radiation intensity has been experimentally observed under resonant magnetic perturbation (RMP) fields on the EAST tokamak. To study the reduction in W radiation during RMP application, dedicated integrated modelling has been conducted using MARS-F code, EMC3-EIRENE code and OMFIT framework. The impacts of divertor target erosion, edge magnetic topology and perpendicular transport on W radiation have been systematically investigated in this work. The simulation results indicate that the changes in both the edge magnetic topology and the divertor sputtering coefficient under RMP fields tend to increase, rather than decrease, the W radiation level. In contrast, only an increase in the perpendicular transport coefficient of W impurities within the RMP-induced three-dimensional (3D) scrape-off layer (SOL) leads to consistency with the experimentally observed radiation mitigation. These findings identify the enhancement of perpendicular transport in the 3D SOL as the dominant contributor to the suppression of W accumulation by RMP, thereby offering valuable insights into the mechanisms of impurity control on EAST.
This paper investigates how resonant magnetic perturbations (RMPs) can reduce tungsten (W) radiation in the EAST tokamak. The study uses advanced simulations to show that increased perpendicular transport of W impurities in the 3D scrape-off layer is the key factor, rather than changes in divertor erosion or edge topology.