In this study, the effects of impurity seeding on the one- and two-dimensional heat flux profiles of the large helical device divertor with a multi-peaks of heat flux were investigated, focusing on the heat-flux-reduction characteristics at the two peaks. The divertor heat flux profile was reconstructed using finite element analysis based on the temperature distribution measured via infrared thermography. The divertor heat flux profiles were calculated using the EMC3-EIRENE code considering the impurity seeding. In general, the calculated results were consistent with the experimental observations, including the heat flux value and reduction via impurity seeding. The reduction in the divertor heat flux due to impurity seeding was almost similar at different heat flux peaks and exhibited little dependence on the heating power variance. The difference between the low- and high-heating-power cases is discussed by tracing the magnetic field lines from the divertor plate and considering the penetration depth of the impurity particles into the scrape-off layer plasma.
This paper investigates the effects of impurity seeding on the heat flux profiles of a large helical device divertor with multiple heat flux peaks. The study focuses on understanding the heat flux reduction characteristics at these peaks. The results show that the heat flux reduction due to impurity seeding is similar across the different peaks and is not strongly affected by changes in heating power.