EMC3-EIRENE modeling of toroidally-localized divertor gas injection experiments on Alcator C-Mod

TY - JOUR

T1 - EMC3-EIRENE modeling of toroidally-localized divertor gas injection experiments on Alcator C-Mod

AU - Lore, J. D.

AU - Reinke, M. L.

AU - LaBombard, B.

AU - Lipschultz, B.

AU - Churchill, R. M.

AU - Pitts, R. A.

AU - Feng, Y.

PY - 2015/8

Y1 - 2015/8

N2 - Abstract Experiments on Alcator C-Mod with toroidally and poloidally localized divertor nitrogen injection have been modeled using the three-dimensional edge transport code EMC3-EIRENE to elucidate the mechanisms driving measured toroidal asymmetries. In these experiments five toroidally distributed gas injectors in the private flux region were sequentially activated in separate discharges resulting in clear evidence of toroidal asymmetries in radiated power and nitrogen line emission as well as a ∼50% toroidal modulation in electron pressure at the divertor target. The pressure modulation is qualitatively reproduced by the modeling, with the simulation yielding a toroidal asymmetry in the heat flow to the outer strike point. Toroidal variation in impurity line emission is qualitatively matched in the scrape-off layer above the strike point, however kinetic corrections and cross-field drifts are likely required to quantitatively reproduce impurity behavior in the private flux region and electron temperatures and densities directly in front of the target

AB - Abstract Experiments on Alcator C-Mod with toroidally and poloidally localized divertor nitrogen injection have been modeled using the three-dimensional edge transport code EMC3-EIRENE to elucidate the mechanisms driving measured toroidal asymmetries. In these experiments five toroidally distributed gas injectors in the private flux region were sequentially activated in separate discharges resulting in clear evidence of toroidal asymmetries in radiated power and nitrogen line emission as well as a ∼50% toroidal modulation in electron pressure at the divertor target. The pressure modulation is qualitatively reproduced by the modeling, with the simulation yielding a toroidal asymmetry in the heat flow to the outer strike point. Toroidal variation in impurity line emission is qualitatively matched in the scrape-off layer above the strike point, however kinetic corrections and cross-field drifts are likely required to quantitatively reproduce impurity behavior in the private flux region and electron temperatures and densities directly in front of the target

UR - http://www.scopus.com/inward/record.url?scp=84937734366&partnerID=8YFLogxK

U2 - 10.1016/j.jnucmat.2014.09.053

DO - 10.1016/j.jnucmat.2014.09.053

M3 - Article

AN - SCOPUS:84937734366

SN - 0022-3115

VL - 463

SP - 515

EP - 518

JO - Journal of Nuclear Materials

JF - Journal of Nuclear Materials

T2 - Proceedings of the 21st International Conference on Plasma-Surface Interactions in Controlled Fusion Devices

Y2 - 26 May 2014 through 30 May 2014

ER -