The reporter learned from the Hefei Institute of Physical Science of the Chinese Academy of Sciences that the research group of Sun Youwen, a member of the EAST team of the Institute of Plasma Physics of the Chinese Academy of Sciences, has made new progress in the study of the thermal load of the divertor target using the three-dimensional rotating magnetic disturbance field on the EAST. Recently, it was published in the fusion field journal "Nuclear Fusion". Through cooperation with the U.S. General Atomic Energy research team, the research group further extended this result to DRI-D devices in the US to study the magnetic perturbation field in the rotating and mixed perturbation mode. Recently, relevant results were published in "Plasma Physics" and were invited by the 59th American Physics Society Plasma Conference as an invitation.
Divertor target heat load control is a huge challenge for future magnetic confinement fusion reactors such as ITER (International Thermonuclear Reactor Project). The applied magnetic disturbance field has been proved to be able to weaken or suppress the boundary local mode, and thus effective Relieving the impact of transient strong local thermal moduli on the divertor target due to the local boundary mode of the boundary. At the same time, how to reduce the cumulative effect of circumferential asymmetric local target heat flow caused by the three-dimensional field is still the research field. The unsolved puzzle.
The research group carried out the boundary local model control experiment on the EAST by using the magnetic field with the external rotation of the ring rotation. It was found that the particle flow distribution on the target plate during the magnetic perturbation shows a circular asymmetrical split structure. This structure rotates with rotation. The magnetic perturbation field rotates synchronously along the hoop direction of the target plate, confirming the effectiveness of this control method. Through the magnetic perturbation spectrum scan, it was found that the local particle flow distribution of the split structure can also be distributed along with the suppression effect. The target plate moves in a wider range. These experimental results show that the time-varying disturbance field is beneficial to the homogenization of the particle flow and the heat flow over the entire target plate, avoiding local overheating of the target plate.
Based on this result, the research team collaborated with the DIII-D research team of the United States to further develop a control experiment for the low-impact-rate down-mixed-circular-modulus n-rotation magnetic perturbation field on the DIII-D device. While the static disturbance component is used to maintain the local mode suppression at the boundary, the heat component and the particle flow on the target plate are successfully controlled using the rotation component. These results will be used to control the target in a magnetic confinement fusion device using three-dimensional magnetic disturbances in the future. The related technical development and physics understanding of the board transient heat load have important impetus.
Source: Science and Technology Daily
