Preliminary thermal hydraulic analyses on electrostatic residual ion dump for CRAFT NNBI

Neutral beam injection is an important auxiliary heating and current driving method for magnetic confinement fusion research. In order to better build the Neutral Beam Injector with Negative Ion Source (NNBI), the pre-research on key technologies has been carried out for the Comprehensive Research Facility for Fusion Tech-nology (CRAFT). Combined with the theoretical design, the maximum heat deposition distribution on the surface of the polar plate in the case of normal operation is analyzed. Then, according to the actual heating load on the surface of the polar plate, the heat removal simulation under the optimized beam power distribution is carried out. The improvement of the heat transfer performance of the water-cooled structure by the spoiler structure is simulated. The results show that the water-cooled structure of the electrostatic residual ion dump can meet the heat removal requirements of the system.