3D non-linear MHD simulation of the MHD response and density increase as a result of shattered pellet injection

Nuclear Fushion

article

D. Hu¹  E. Nardon²  M. Lehnen¹  G.T.A. Huijsmans²  D.C. van Vugt³  JET Contributors⁴ 

[1] ITER Organization;CEA;Eindhoven University of Technology;EUROfusion Consortium, JET, Culham Science Centre

关键词: tokamak;    MHD instability;    shattered pellet injection;    JOREK;    reduced MHD;    simulation;    disruption mitigation;   

DOI  :  10.1088/1741-4326/aae614

来源: Institute of Physics Publishing Ltd.

【 摘 要 】

The MHD response and the penetration of a deuterium shattered pellet into a JET plasma is investigated via the non-linear reduced MHD code JOREK with the neutral gas shielding (NGS) ablation model. The dominant MHD destabilizing mechanism by the injection is identified as the local helical cooling at each rational surface, as opposed to the global current profile contraction. Thus the injected fragments destabilize each rational surface as they pass through them. The injection penetration is found to be much better compared to MGI, with the convective transport caused by core MHD instabilities (e.g. 1/1 kink) contributing significantly to the core penetration. Moreover, the injection with realistic JET SPI system configurations is simulated in order to provide some insights into future operations, and the impact on the total assimilation and penetration depth of varying injection parameters such as the injection velocity or fineness of shattering is assessed. Further, the effect of changing the target equilibrium temperature orqprofile on the assimilation and penetration is also investigated. Such analysis will form the basis of further investigation into a desirable configuration for the future SPI system in ITER.

【 授权许可】

Unknown