Impact of drifts in edge plasma of small size divertor tokamak

Abstract

The effect of poloidal E × B and diamagnetic drifts in edge plasma of Small Size Divertor (SSD) Tokamak is studied with two-dimensional B2SO- LPS-0.5.2D fluid transport code. The simulation results show the following: 1) For normal toroidal magnetic field, the increasing of core plasma density leads to large divertor asymmetries due to poloidal E × B and diamagnetic drifts. 2) Switching on the E × B and diamagnetic drifts leads to large change in poloidal distribution of radial electric field and induced counter-clockwise circulation (flow) around the x-point. 3) Switching on the E × B and diamagnetic drifts leads to the structure of poloidal distribution of radial electric field is nonmonotonic which responsible for negative spikes. 4) Switching on the E × B and diamagnetic drifts in vicinity of separatrix leads to the structure of poloidal distribution of radial electric field that has viscous layer. 5) Switching on the E × B and diamagnetic drifts results in torque generation. This torque spins up the toroidal rotation. 6) The E × B drift velocity depends on the plasma temperature heating and doesn't depend on plasma density.

Share and Cite:

Bekheit, A. (2012) Impact of drifts in edge plasma of small size divertor tokamak. Natural Science, 4, 131-135. doi: 10.4236/ns.2012.42019.

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1] Hutchinson, I.H, LaBombard, B., Goetz, J.A., Lipschultz, B., McCracken, G.M., Snipes, J.A. and Terry, J.L. (1995) The effects of field reversal on the Alcator C-Mod divertor. Plasma Physics and Controlled Fusion, 37, 1389- 1406. doi:10.1088/0741-3335/37/12/004
[2] Tsois, N., Dorn, C., Kyriadakis, G., Markoulaki, M., Pfug, M., Schramm, G. and ASDEX-Upgread team (1999) A fast scaning langmuir probe system for ASDEX-Upgread Divertor. Journal of Nuclear Materials, 266-269, 1230- 1233. doi:10.1016/S0022-3115(98)00569-8
[3] Pitts, R.A, Andrew, P., Bonnin, X., Chankin, A.V, Corre, Y., Corrigan, G., Coster, D., Duran, I., Eich, T. and contributors to the EFDA-JET workprogramme (2005) Edge and divertor physics with reversed toroidal field in JET. Journal of Nuclear Materials, 337-339, 146-153. doi:10.1016/j.jnucmat.2004.10.111
[4] Ou, J., Zhu, S. (2007) Numerical predictions of the poloidal E × B drift in EAST. Journal of Nuclear Materials, 363, 633-637.
[5] Bekheit, A. H. and Gaber, W.H. (2010) B2SOLPS0.5.2D code simulations of sol flows and drifts effects in the edge plasma of small size divertor tokamak. Journal of Fusion Energy, 29, 261-266. doi:10.1007/s10894-009-9270-6
[6] Rognlien, T.D., Porter, G.D. and Ryutov, D.D. (1999) Influence of E × B and ?B drift terms in 2-D edge/SOL transport simulations. Journal of Nuclear Materials, 266- 269, 654-659. doi:10.1016/S0022-3115(98)00835-6
[7] Braginskii, S.I. (1965) Transport Processes in Plasma. Reviews of Plasma Physics, 1, 205.
[8] Rognlien, T.D. and Ryutov, D.D. (1998) Analysis of classical transport equations for the tokamak edge plasma. Contributions to Plasma Physics, 38, 152-157. doi:10.1002/ctpp.2150380123
[9] Rognlien, T.D., Ryutov, D.D., Mattor, N. and Porter, G.D. (1999) Two-dimensional electric fields and drifts near the magnetic separatrix in divertor tokamaks. Physics of Plasmas, 6, 1851. doi:10.1063/1.873488
[10] Radford, G.J., Chankin, A.V, Corrigan, G., Simonini, R., Spence, J. and Taroni, A. (1996) The particle and heat drift fluxes and their implementation into the EDGE2D transport code. Contributions to Plasma Physics, 36, 187-191. doi:10.1002/ctpp.2150360217
[11] Gerhauser, R., Zagórski, R., Gerhauser, H. and Claa?en, H.A. (1998) Numerical simulation of the TEXTOR edge plasma including drifts and impurities. Contributions to Plasma Physics, 38, 61-67. doi:10.1002/ctpp.2150380110
[12] Schneider, R., Rozhansky, V., Voskoboynikov, V. (2001) Simulation of tokamak edge plasma including self-consistent electric fields. Nuclear Fusion, 41, 387. doi:10.1088/0029-5515/41/4/305
[13] Bekheit, A.H. (2008) Simulation of small size divertor tokamak plasma edge including self-consistent electric fields. Journal of Fusion Energy, 27, 338-345. doi:10.1007/s10894-008-9148-z
[14] Rozhansky, V., Kaveeva, E., Voskoboynikov, S., Counsell, G., Kirk, A., Meyer, H., Coster, D., Conway, G., Schirmer, J., Schneider, R. and the ASDEX Upgrade Team (2006) Modelling of radial electric field profile for different divertor configurations. Plasma Physics and Controlled Fusion, 48, 1425-1435. doi:10.1088/0741-3335/48/9/011
[15] Rozhansky, V., Kaveeva, E., Voskoboynikov, S., Bonnin, X. and Schneider, R. (2004) Understanding transport barriers through modeling. Nuclear Fusion, 42, 1110. doi:10.1088/0029-5515/42/9/309
[16] Rozhansky, V. (2004) Understanding transport barriers through modeling. Plasma Physics and Controlled Fusion, 46, A1. doi:10.1088/0741-3335/46/5A/001
[17] Rozhansky, V., Rozhansky, V., Kaveeva, E., Voskoboynikov, S., Bonnin, X. and Schneider, R., et al. (2003) Modelling of electric fields in tokamak edge plasma and L-H transition. Nuclear Fusion, 43, 1.

Copyright © 2024 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.