Results 131 to 140 of about 52,799 (163)

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., Moyer, R., 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., Lönnroth, J., Shimada, M., Polevoi, A., Federici, G.   +45 more
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Edge-localized modes - physics and theory

Plasma Physics and Controlled Fusion, 1998
The phenomenology of ELMs is reviewed, emphasizing the conditions for their occurrence, their repetition frequencies, their impact on confinement and the properties of associated fluctuations, in order to understand the physics involved. Theories of ELMs are then briefly described and the extent to which they can successfully model ELMs is discussed.
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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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Intrinsic localized anharmonic modes at surfaces and edges

Physica B: Condensed Matter, 1996
Abstract On the basis of realistic lattice-dynamical models, anharmonic modes have been found at surfaces and edges of crystal lattices. Their associated displacements are not only localized in the direction(s) perpendicular, but also parallel to the surface or the tip of the edge. The stability of such modes is tested by molecular dynamics.
U. Schröder, D. Bonart, A.P. Mayer
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Shear flows at the tokamak edge and their interaction with edge-localized modes

Physics of Plasmas, 2007
Shear flows in the scrape-off layer (SOL) and the edge pedestal region of tokamaks are shown to arise naturally out of transport processes in a magnetohydrodynamic model. In quasi-steady-state conditions, collisional resistivity coupled with a simple bootstrap current model necessarily leads to poloidal and toroidal flows, mainly localized to the edge ...
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Edge localized vibration modes on a rectangular ridge

Journal of Applied Physics, 1977
We present a theory of elastic waves which propagate along a semi-infinite rectangular ridge made up of a nonpiezoelectric elastic medium, and which are localized at the top and sides of the ridge. Stress-free boundary conditions are incorporated into the calculation by the assumption of position-dependent elastic moduli. The equations of motion of the
A. A. Maradudin, K. R. Subbaswamy
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Effect of resistivity on small edge localized mode

Physics of Plasmas, 2018
The effect of resistivity on small edge localized mode (ELM) is investigated based on the peeling-ballooning three-field module of BOUT++. The ELM size increases with increasing resistivity, which is attributed to both linear growth rate and turbulence intensity.
N. Wu, S. Y. Chen, M. L. Mou, C. J. Tang
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Nonlinear magnetohydrodynamics of edge localized mode precursors

Physics of Plasmas, 2015
A possible origin of edge-localized-mode (ELM) precursors based on nonlinear ideal peeling-ballooning mode is reported. Via nonlinear variational principle, a nonlinear evolution equation of the radial displacement is derived and solved, analytically.
Z. B. Guo, Lu Wang, X. G. Wang
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Effect on confinement of edge-localized modes in TCV

Plasma Physics and Controlled Fusion, 1996
The effect of ELMs on confinement in ohmic H-modes has been investigated by analysing the rates of change of global parameters such as the electron content and the stored energy as a function of ELM frequency. In double-null H-modes, ELMs are found to expel on average 2% of the electron content and 2.5% of the stored energy.
Weisen, H., Dutch, M. J., Hofmann, F., Martin, Y., Moret, J. M., Nieswand, C., Pietrzyk, Z. A., Pitts, R. A., Pochelon, A.   +8 more
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Density edge localized modes in rotating plasmas

Nuclear Fusion, 1996
A linear analysis is presented for the density edge localized mode with realistic tokamak edge plasma and electric field profiles. The mode is driven unstable by the electron temperature gradient and is localized by the density pedestal, with a radial mode width proportional to the square root of the density scale length (in H mode).
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