Tungsten core accumulation study in EAST plasma with lower tungsten divertor by kinetic impurity transport model

Wu, Yihan; Zhou, Qingrui; Sang, Chaofeng; Zhang, Yanjie; Wang, Yilin; Wang, Dezhen

doi:10.1016/j.nme.2022.101297

Cited by 5 publications

(3 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The new version of SOLPS-ITER with extended grids [38] will be used in future work to consider the plasma first wall interaction. Moreover, the process of prompt redeposition is not considered in the fluid treatment of W impurities, and it requires the kinetic treatment of the W impurity [39].…”

Section: Discussionmentioning

confidence: 99%

The influence of E× B drift on tungsten target erosion and W impurity transport during neon seeding on EAST

et al. 2023

Self Cite

View full text Add to dashboard Cite

Mitigating tungsten (W) wall erosion and core accumulation is vitally important to the steady-state operation of tokamaks. It is well known that drifts have a great impact on the transport of charged particles in the edge region, which could affect W source and W impurity transport. In this work, SOLPS-ITER modeling is applied to study the W impurity behavior on EAST during neon seeding with the consideration of E×B drift. The objective is to find out the relationship between the eroded W flux, W transport and corresponding accumulation in core in different discharge regimes. The effect of drift on W sputtering at targets and W impurity distribution in the cases of different toroidal magnetic field (Bt) directions is assessed. The simulation results indicate that drift could influence W transport via W impurity retention and redistribution in divertor, and the leakage from divertor. In forward Bt (B×∇B points to the X-point), eroded W flux at outer target is increased remarkably, and most of the W ions transport from outer to inner divertor and escape to upstream region in high field side. While W ions mainly transport from inner to outer divertor and escape from divertor in low field side in reversed Bt due to the opposite drift flux. Ne puffing rate is scanned in forward Bt and without drift cases to further investigate the W erosion and W impurity transport in different divertor regimes. It is found that W source from targets is generally enhanced by drift compared to the without drift cases. The core accumulation as well as poloidal asymmetry is also influenced significantly by the drift. In attached regime, intense W source and strong drift flux lead to enhanced W accumulation in the core, and obvious poloidal asymmetry of W density distribution appears. The drift flux is reduced, and W erosion is suppressed after detachment. W concentration in the core and poloidal asymmetry declines consequently. Therefore, adequate Ne impurity seeding can be applied to control the W accumulation in the core.

show abstract

Section: Discussionmentioning

confidence: 99%

The influence of E× B drift on tungsten target erosion and W impurity transport during neon seeding on EAST

et al. 2023

Self Cite

View full text Add to dashboard Cite

show abstract

“…Thus, the effect of E × B drift on W transport can be understood by studying its influence on Γ W in detail. It should be noted that if D ⊥,W is much lower than the typical value of 1 m 2 s −1 used in this work, the flow pattern discussed below will be modified [33,79].…”

Section: Statistics Of the Effects Of E × B Drift On The Three Stages...mentioning

confidence: 92%

Simulation study of the influence of E× B drift on tungsten impurity transport in the scrape-off layer

Guo,

Xu,

Mao

et al. 2023

Nucl. Fusion

View full text Add to dashboard Cite

Future fusion reactors such as ITER have adopted tungsten (W) as the plasma-facing materials (PFMs) in the divertor region. It is crucial to keep the W concentration in the core plasma at an extremely low level. Great efforts have been put forward on understanding the W transport in the scrape-off layer (SOL), which is related to the source of the core W contamination. In this work, the influence of E×B drift on the W impurity transport in the SOL is studied by numerical simulations for a model case based on EAST upper single-null configuration with high recycling divertor plasma. The W transport is simulated using DIVIMP on the background plasma obtained from SOLPS-ITER simulation including drifts. The E×B drift of the W ions is introduced according to the background electric field. Therefore, both the direct E×B drift effect of W ion itself and the indirect effect via background plasma on the W transport process in the SOL can be studied. We focus on the influence on the flux of W impurities entering confined plasma across the last closed flux surface Γenter, which is expected to be proportional to the core W concentration. It is found that Γenter is mainly from the outer (inner) target under favorable (unfavorable) toroidal field BT, and can be increased by more than one order of magnitude compared with the case without drifts. It reflects the significant influence of E×B drift effects. The detailed effects due to the background plasma and the poloidal and radial E×B drift of W ion, as well as the related mechanisms, are analyzed for the three stages of W transport in the SOL, including the effective sputtering from the target, the leakage from the divertor and the entry into the confined plasma.

show abstract

“…The code is verified by benchmarking against the DIVIMP code and is coupled to edge plasma code SOLPS to study W core accumulation in EAST. It is found the competition between friction force and ion temperature gradient force significantly affects the penetration of W impurity to the core region and the enhancement of anomalous diffusion suppresses W core accumulation [49].…”

Section: Edge Physicsmentioning

confidence: 99%

Summary of the 10th Conference on Magnetically Confined Fusion Theory and Simulation (CMCFTS)

Wang

Qiu

Wang

et al. 2023

Plasma Sci. Technol.

View full text Add to dashboard Cite

This paper gives a summary of the organization and the presentations delivered at the 10th Conference on Magnetically Confined Fusion Theory and Simulation (CMCFTS) held in Zhuhai, China, from 28th to 31st October 2022. The conference focused on the latest progress in the research of the magnetic confined fusion plasma theory and simulations, as well as the large-scale numerical simulation techniques developed in recent years. This conference is held both online and offline, with about 110 domestic participants from 18 institutes participating in the live conference, and the statistical data from the live broadcast platform indicated that the online conference attracted over 20000 views per day. A summary of the conference is given, and the history of the CMCFTS is presented. A brief introduction to the poster section is also included in this paper.

show abstract

Tungsten core accumulation study in EAST plasma with lower tungsten divertor by kinetic impurity transport model

Cited by 5 publications

References 24 publications

The influence of E× B drift on tungsten target erosion and W impurity transport during neon seeding on EAST

The influence of E× B drift on tungsten target erosion and W impurity transport during neon seeding on EAST

Simulation study of the influence of E× B drift on tungsten impurity transport in the scrape-off layer

Summary of the 10th Conference on Magnetically Confined Fusion Theory and Simulation (CMCFTS)

Contact Info

Product

Resources

About