Simulation study of the influence of the cross-field anomalous diffusion on the tungsten impurity transport in the scrape-off layer with activated drifts

Tungsten (W) impurity eroded from the divertor target can degrade the confinement performance of future fusion reactors. The mechanism of the effect of E x B drift on the W transport in the scrape-off layer (SOL) was investigated with a fixed cross-field anomalous particle diffusion coefficient for W ions (D perpendicular to,W) of 1 m2s-1 in our previous simulation work, which indicates that the W flux entering the confined region (Gamma enter) and mean W concentration in the confined region (CWavg$$ {C}_{\mathrm{W}}<^>{\mathrm{avg}} $$) can be increased by more than one order of magnitude by drifts. In this work, the influence of the cross-field anomalous diffusion on the W transport in the SOL is further investigated. The basic flow pattern of the W ion flux (Gamma W) keeps when D perpendicular to,W varying from 0.5 to 3 m2s-1, and Gamma enter mainly comes from the hotter divertor region. Results show that D perpendicular to,W value affects the W leakage from divertor region and entry into confined region. Therefore, Gamma enter and CWavg$$ {C}_{\mathrm{W}}<^>{\mathrm{avg}} $$ both decrease with increasing D perpendicular to,W. Mechanisms for cases w/wo drifts are compared.