Staged cooling of a fusion-grade plasma in a tokamak thermal quench

Nuclear Fushion

article

Jun Li¹  Yanzeng Zhang¹  Xian-Zhu Tang¹ 

[1] Theoretical Division, Los Alamos National Laboratory;School of Nuclear Science and Technology, University of Science and Technology of China

关键词: staged cooling;    thermal quench;    convection;    conduction;    tokamak disruption;   

DOI  :  10.1088/1741-4326/acce4c

来源: Institute of Physics Publishing Ltd.

【 摘 要 】

In tokamak disruptions where the magnetic connection length becomes comparable to or even shorter than the plasma mean-free-path, parallel transport can dominate the energy loss and the thermal quench of the core plasma goes through four phases (stages) that have distinct temperature ranges and durations. The main temperature drop occurs while the core plasma remains nearly collisionless, with the parallel electron temperature T_{eparallel}dropping in timetas T_{eparallel}propto t^{-2}and a cooling time that scales with the ion sound wave transit time over the length of the open magnetic field line. These surprising physics scalings are the result of effective suppression of parallel electron thermal conduction in an otherwise bounded, quasineutral, and collisionless plasma, which is different from what are known to date on electron thermal conduction along the magnetic field in a nearly collisionless and quasineural plasma.

【 授权许可】

Unknown