Results 221 to 230 of about 48,929 (262)

Model for Current-Driven Edge-Localized Modes

Physical Review Letters, 2006
Edge-localized modes (ELMs) are cyclic disturbances in the outer region of tokamak plasmas that are influential in determining present and future tokamak performance. In this Letter, we outline an approach to modeling ELMs in which we envisage toroidal peeling modes initiating a Taylor relaxation [Phys. Rev. Lett.
C G, Gimblett, R J, Hastie, P, Helander
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Edge-localized modes and edge transport in spherical tokamaks

Physics of Plasmas, 2005
Turbulent energy transport in numerical simulations of the edge region of spherical tokamaks with small toroidal aspect ratio A=1.5 is directly compared to that in conventional tokamaks with larger aspect ratio A=3. Depending upon the aspect ratio of the torus, the energy flux can vary greatly.
Robert G. Kleva, Parvez N. Guzdar
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Edge localized modes (ELMs)

Plasma Physics and Controlled Fusion, 1996
The phenomenology of edge localized modes (ELMs), an MHD instability occurring in the edge of H-mode plasmas in toroidal magnetic fusion experiments, is described. ELMs are important to obtain experimental control of the particle inventory of fusion plasmas.
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Studies of edge localized modes on ASDEX

Nuclear Fusion, 1992
The MHD behaviour connected with edge localized modes (ELMs) is studied using fast sample rate fluctuation diagnostics. It is found that ELMs on ASDEX are generally preceded by a coherent MHD mode of medium poloidal mode number (m=10-15). At the onset of the ELM the mode behaviour changes to a turbulent one, leading to an outflux of heat and particles.
Zohm, Hartmut, Wagner, F., Endler, M., Gernhardt, J., Holzhauer, E., Kerner, W., Mertens, V.   +6 more
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Edge Localized Modes in Tokamaks

Fusion Science and Technology, 2012
As one increases the heating power in a tokamak beyond a threshold, the confinement undergoes a bifurcation, with a dramatic increase in the confinement time by a factor ~2.
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Magnetohydrodynamic activity during edge localized modes on ASDEX

Nuclear Fusion, 1990
Magnetohydrodynamic (MHD) activity during edge localized modes (ELMs) has been monitored in the ASDEX tokamak. Besides a fast inward shift of the plasma column, a helical MHD perturbation has been found to accompany ELMs. For the discharges investigated, the helical instability has a poloidal mode number m of 3 or 4 and a toroidal mode number n of 1 ...
Von Goeler, S., Klueber, O., Fussmann, G., Gernhardt, J., Kornherr, M.   +4 more
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Characteristics of the edge localized mode in the JFT-2M H-mode

Nuclear Fusion, 1991
The characteristics of the edge localized model (ELM), also referred to as edge relaxation phenomenon, were investigated in H-mode plasmas of JFT-2M. It was found that the ELM is mainly a density fluctuation phenomenon at the edge and that the electron temperature at the edge, except near the separatrix, is not very strongly perturbed.
H. Matsumoto, R.J. Goldston, A. Funahashi, K. Hoshino, H. Kawashima, T. Kawakami, H. Maeda, T. Matoba, T. Matsuda, Y. Miura, M. Mori, K. Odajima, H. Ogawa, T. Ogawa, K. Ohasa, S. Sengoku, T. Shoji, N. Suzuki, H. Tamai, Y. Uesugi, T. Yamauchi, T. Yamamoto   +21 more
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Edge localized modes control: experiment and theory

Journal of Nuclear Materials, 2005
The paper reviews recent theoretical and experimental results focussing on the identification of the key factors controlling ELM energy and particle losses both in natural ELMs and in the presence of external controlling mechanisms. Present experiment and theory pointed out the benefit of the high plasma shaping, high q(95) and high pedestal density in
Becoulet, M., Huysmans, G., Thomas, P., Joffrin, E., Rimini, F., Monier-Garbet, P., Grosman, A., Ghendrih, P., Parail, V., Lomas, P., Matthews, G., Wilson, H., Gryaznevich, M., Counsell, G., Loarte, A., Saibene, G., Sartori, R., Leonard, A., Snyder, P., Evans, T., Gohil, P., Moyer, R., Kamada, Y., Oyama, N., Hatae, T., Kamiya, K., Degeling, A., Martin, Y., Lister, J., Rapp, J., Perez, C., Lang, P., Chankin, A., Eich, T., Sips, A., Stober, J., Horton, L., Kallenbach, A., Suttrop, W., Saarelma, S., Cowley, S., Lonnroth, J., Shimada, M., Polevoi, A., Federici, G.   +44 more
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The physics of large and small edge localized modes

Plasma Physics and Controlled Fusion, 2000
The operational boundaries for the occurrence of various types of edge localized mode (ELM) instability in high-confinement-mode (H-mode) fusion plasmas are reviewed. The phenomenology of ELMs and the occurrence of different ELM types in parameter space are described.
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Dynamics of edge localized modes in the TCV tokamak

Plasma Physics and Controlled Fusion, 2001
The Dα emission time-series from the TCV tokamak was investigated for a large set of ELMy discharges, to determine whether fluctuations in the time delay between ELMs are the result of noise only, or whether a deterministic process in a chaotic state exists, as suggested by results on JT-60U (Bak \textit{et al} 1999 \textit{Phys. Rev. Lett.} \textbf{83}
Degeling, A. W., Martin, Y. R., Bak, P. E., Lister, J. B., Llobet, V.   +4 more
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