Speaker
Xiaoju Liu
(Institute of plasma physics chinese academy of sciences)
Description
The Chinese Fusion Engineering Test Reactor (CFETR) is under design. Divertor is the most pivotal PFC to manage power and He ash exhaust. Based on the main goal of CFETR, it has a similar P/R~14 MW/m to ITER. Impurity seeding has been considered a promising means to enhance the radiation from the plasma edge and hence to reduce the target heat load, especially on carbon-free wall conditions. We have simulated the baseline operation scenario parameters by using SOLPS5.0 (B2.5-EIRENE) code package for a vertical lower single null (LSN) divertor configuration. The modeling shows that the peak heat load at divertor targets significantly exceeds the maximum engineering limit (i.e. 10 MW/m22) for the low density steady-state operations without any impurities puffing. The SOLPS simulations also demonstrate that Ar (or Ne, N2) puffing from the top of CFETR device is highly effective in mitigation of the divertor peak heat flux to below 10 MW/m22, and both inner and outer divertor plates achieve detachment near the strike point with puffing rate reach a certain high level for the low density operation. In addition, the radiation loss fraction inside the separatrix will enhances and leads a reduction of the power flux across separatrix as impurities puff rate increase. Further simulations of different divertor geometries and configurations will be performed to optimize CFETR design.
Co-author
Xiaoju Liu
(Institute of plasma physics chinese academy of sciences, Hefei, China)