Injected mass deposition thresholds for lithium granule instigated triggering of edge localized modes on EAST

Lunsford, R; Sun, Z; Maingi, R; Hu, J S; Mansfield, D; Xu, W; Zuo, G Z; Diallo, A; Osborne, T; Tritz, K; Canik, J; Huang, M; Meng, X C; Gong, X Z; Wan, B N; Li, J G

doi:10.11578/1562089

Title: Injected mass deposition thresholds for lithium granule instigated triggering of edge localized modes on EAST

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Abstract

The ability of an injected lithium granule to promptly trigger an edge localized mode (ELM) has been established in multiple experiments. By horizontally injecting granules ranging in diameter from 200 microns to 1mm in diameter into the low field side of EAST H-mode discharges we have determined that granules with diameter > 600 microns are successful in triggering ELMs more than 95% of the time. It was also demonstrated that below 600 microns the triggering efficiency decreased roughly with granule size. Granules were radially injected from the outer midplane with velocities ~ 80 m/s into EAST upper single null discharges with an ITER like tungsten monoblock divertor. These granules were individually tracked throughout their injection cycle in order to determine their efficacy at triggering an ELM. For those granules of sufficient size, ELM triggering was a prompt response to granule injection. By simulating the granule injection with an experimentally benchmarked neutral gas shielding (NGS) model, the ablatant mass deposition required to promptly trigger an ELM is calculated and the fractional mass deposition is determined.

Authors:

Lunsford, R; Sun, Z; Maingi, R; Hu, J S; Mansfield, D; Xu, W; Zuo, G Z; Diallo, A; Osborne, T; Tritz, K; Canik, J; Huang, M; Meng, X C; Gong, X Z; Wan, B N; Li, J G

OSTI

Publication Date:: Fri Dec 01 04:00:00 UTC 2017

DOE Contract Number:: AC02-09CH11466

Research Org.:: Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)

Sponsoring Org.:: U. S. Department of Energy

Subject:: H-mode

OSTI Identifier:: 1562089

DOI:: https://doi.org/10.11578/1562089

Citation Formats


                    Lunsford, R, Sun, Z, Maingi, R, Hu, J S, Mansfield, D, Xu, W, Zuo, G Z, Diallo, A, Osborne, T, Tritz, K, Canik, J, Huang, M, Meng, X C, Gong, X Z, Wan, B N, and Li, J G. Injected mass deposition thresholds for lithium granule instigated triggering of edge localized modes on EAST.  United States: N. p., 2017. 
        Web.  doi:10.11578/1562089.

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                    Lunsford, R, Sun, Z, Maingi, R, Hu, J S, Mansfield, D, Xu, W, Zuo, G Z, Diallo, A, Osborne, T, Tritz, K, Canik, J, Huang, M, Meng, X C, Gong, X Z, Wan, B N, & Li, J G. Injected mass deposition thresholds for lithium granule instigated triggering of edge localized modes on EAST.  United States.  doi:https://doi.org/10.11578/1562089

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                    Lunsford, R, Sun, Z, Maingi, R, Hu, J S, Mansfield, D, Xu, W, Zuo, G Z, Diallo, A, Osborne, T, Tritz, K, Canik, J, Huang, M, Meng, X C, Gong, X Z, Wan, B N, and Li, J G. 2017.  
"Injected mass deposition thresholds for lithium granule instigated triggering of edge localized modes on EAST".  United States.  doi:https://doi.org/10.11578/1562089.  https://www.osti.gov/servlets/purl/1562089. Pub date:Fri Dec 01 04:00:00 UTC 2017

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@article{osti_1562089,

  title        = {Injected mass deposition thresholds for lithium granule instigated triggering of edge localized modes on EAST},

  author       = {Lunsford, R and Sun, Z and Maingi, R and Hu, J S and Mansfield, D and Xu, W and Zuo, G Z and Diallo, A and Osborne, T and Tritz, K and Canik, J and Huang, M and Meng, X C and Gong, X Z and Wan, B N and Li, J G},

  abstractNote = {The ability of an injected lithium granule to promptly trigger an edge localized mode (ELM) has been established in multiple experiments. By horizontally injecting granules ranging in diameter from 200 microns to 1mm in diameter into the low field side of EAST H-mode discharges we have determined that granules with diameter > 600 microns are successful in triggering ELMs more than 95% of the time. It was also demonstrated that below 600 microns the triggering efficiency decreased roughly with granule size. Granules were radially injected from the outer midplane with velocities ~ 80 m/s into EAST upper single null discharges with an ITER like tungsten monoblock divertor. These granules were individually tracked throughout their injection cycle in order to determine their efficacy at triggering an ELM. For those granules of sufficient size, ELM triggering was a prompt response to granule injection. By simulating the granule injection with an experimentally benchmarked neutral gas shielding (NGS) model, the ablatant mass deposition required to promptly trigger an ELM is calculated and the fractional mass deposition is determined.},

  doi          = {10.11578/1562089},

  journal      = {},

  number       = ,

  volume       = ,

  place        = {United States},

  year         = {Fri Dec 01 04:00:00 UTC 2017},

  month        = {Fri Dec 01 04:00:00 UTC 2017}

}

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DOI: https://doi.org/10.11578/1562089

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