Modeling study of divertor particle and heat flux asymmetries for EAST H-mode discharges

The BOUT + + edge plasma transport code is run to study the effects of plasma drifts on the divertor out-in asymmetries (DOIAs) of particle and heat fluxes and their decay widths for EAST lower single null H-mode discharges. The diamagnetic drift seems to have no effects on the DOIAs of total particle and heat fluxes due to its divergence-free nature. However, it could significantly increase the DOIAs of peak particle and heat fluxes and the flux decay widths. The E×B drift is found to induce a large plasma flow to the divertor region, enhancing the DOIAs of both total and peak particle and heat fluxes and the flux decay widths. Both the radial and poloidal components of the E×B drift are necessary in increasing the DOIAs, however, the radial E×B drift seems to play a more important role. The effects on the DOIAs caused by both diamagnetic and E×B drifts are reversed with the reverse of toroidal magnetic field. The outer target heat flux decay width \({\lambda _q}\) could well match with the multi-machine scaling proposed by Eich and the DOIA of \({\lambda _q}\) is in reasonable agreement with the scaling proposed by Goldston.