Refine your search:     
Report No.
Search Results: Records 1-7 displayed on this page of 7
  • 1

Presentation/Publication Type

Initialising ...


Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...


Initialising ...


Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Pedestal conditions for small ELM regimes in tokamaks

Oyama, Naoyuki; Gohil, P.*; Horton, L. D.*; Hubbard, A. E.*; Hughes, J. W.*; Kamada, Yutaka; Kamiya, Kensaku; Leonard, A. W.*; Loarte, A.*; Maingi, R.*; et al.

Plasma Physics and Controlled Fusion, 48(5A), p.A171 - A181, 2006/05

 Times Cited Count:72 Percentile:91.55(Physics, Fluids & Plasmas)

no abstracts in English

Journal Articles

Characterization of Type-I ELMs in tangential co-, balanced- and counter-plus perpendicular NBI heated plasmas on JT-60U

Kamiya, Kensaku; Urano, Hajime; Koide, Yoshihiko; Takizuka, Tomonori; Oyama, Naoyuki; Kamada, Yutaka; JT-60 Team

Plasma Physics and Controlled Fusion, 48(5A), p.A131 - A139, 2006/05

 Times Cited Count:21 Percentile:59.26(Physics, Fluids & Plasmas)

Effects of plasma rotation and ripple loss on the Type-I ELMs have systematically studied in the JT-60U tokamak, scanning combinations of NBI at the three kinds of plasma volumes. New findings on the Type-I ELMs confirm to be smaller ELM energy loss per pedestal stored energy, DWELM/Wped, and faster ELM frequency, fELM, in the counter-NBI than co-NBI, keeping the power of ELM, PELM, per heating power crossing the separatrix, PSEP, constant. Balanced-NBI case is also intermediate between co- and counter-NBI. In addition, the product of PELM/PSEP decreases according to increase in the plasma volume, suggesting an increase in the inter-ELM transport due mainly to an enhancement in the ripple loss of fast ion.

Journal Articles

Comparisons of small ELM H-mode regimes on the Alcator C-Mod and JFT-2M tokamaks

Hubbard, A. E.*; Kamiya, Kensaku; Oyama, Naoyuki; Basse, N.*; Biewer, T.*; Edlund, E.*; Hughes, J. W.*; Lin, L.*; Porkolab, M.*; Rowan, W.*; et al.

Plasma Physics and Controlled Fusion, 48(5A), p.A121 - A129, 2006/05

 Times Cited Count:15 Percentile:47.9(Physics, Fluids & Plasmas)

Dedicated experiments were carried out to compare the properties, fluctuation behaviour and access conditions of these regimes. A common shape was developed which scaled the plasma boundary except for aspect ratio. Scans of density and input power were carried out at several values of q95, so as to achieve ranges of dimensionless parameters. A striking similarity of access conditions was seen. These results suggest common physical mechanisms for the H-mode regimes, which do not depend critically on aspect ratio over this range. On the other hand, several differences in the details of the edge fluctuations were found, and will be reported. The effect of wall conditioning via boronization on the H-mode regimes will also be discussed.

Journal Articles

Reduced divertor heat loads, plasma shape effects, and radial electric field structures in JFT-2M HRS H-mode plasmas

Kamiya, Kensaku; Kawashima, Hisato; Ido, Takeshi*; Oyama, Naoyuki; Bakhtiari, M.*; Kasai, Satoshi; Kusama, Yoshinori; Miura, Yukitoshi; Ogawa, Hiroaki; Tsuzuki, Kazuhiro; et al.

Nuclear Fusion, 46(2), p.272 - 276, 2006/02

 Times Cited Count:3 Percentile:11.34(Physics, Fluids & Plasmas)

An attractive operational regime without any large ELMs, namely High Recycling Steady (HRS) H-mode, was found on JFT-2M during Y2000 campaign after boronization. Recent experiments have concentrated on the studies of the access conditions for the HRS regime, in terms of the pedestal parameters. The HRS regime was more likely at higher edge density and lower edge temperature, which corresponds to the normalized electron collisionality of 1 in the plasma edge region.

Journal Articles

Scaling of the energy confinement time with $$beta$$ and collisionality approaching ITER conditions

Cordey, J. G.*; Thomsen, K.*; Chudnovskiy, A.*; Kardaun, O. J. W. F.*; Takizuka, Tomonori; Snipes, J. A.*; Greenwald, M.*; Sugiyama, L.*; Ryter, F.*; Kus, A.*; et al.

Nuclear Fusion, 45(9), p.1078 - 1084, 2005/09

 Times Cited Count:51 Percentile:83.86(Physics, Fluids & Plasmas)

The condition of the latest version of the ELMy H-mode database has been re-examined. It is shown that there is bias in the ordinary least squares regression for some of the variables. To address these shortcomings three different techniques are employed: (a)principal component regression, (b)an error in variables technique and (c)the selection of a better conditioned dataset with fewer variables. Scalings in terms of the dimensionless physics valiables, as well as the standard set of engineering variables, are derived. The new scalings give a very similar performance for existing scalings for ITER at the standard beta, but a much improvement performance at higher beta.

Journal Articles

Reduced heat transport between edge-localized-mode bursts at low collisionality and small poloidal larmor radius

Urano, Hajime; Takizuka, Tomonori; Kamada, Yutaka; Oyama, Naoyuki; Takenaga, Hidenobu; Miura, Yukitoshi

Physical Review Letters, 95(3), p.035003_1 - 035003_4, 2005/07

 Times Cited Count:15 Percentile:63.58(Physics, Multidisciplinary)

Non-dimensional parameter dependence of heat transport between ELMs is examined for H mode plasmas. At lower edge collisionality, the heat flux assigned to the heat transport between ELMs is reduced and the ELM loss power is enhanced. During the inter-ELM phase, the energy confinement time becomes larger with decreasing the edge collisionality and poloidal Larmar radius. The electron heat diffusivity between ELMs is reduced to the level of ion neoclassical transport in the plasma edge region which is affected by ELM burst.

Journal Articles

Rapid change of ion energy distribution and floating potential at L/H transition in the JFT-2M tokamak

Miura, Yukitoshi; Nagashima, Keisuke; Ito, Kimitaka; Ito, Sanae*; Okano, Fuminori; Suzuki, Norio; Mori, Masahiro; Hoshino, Katsumichi; Maeda, Hikosuke; Takizuka, Tomonori; et al.

Plasma Physics and Controlled Fusion, 36(7A), p.A81 - A86, 1994/07

 Times Cited Count:5 Percentile:24.54(Physics, Fluids & Plasmas)

no abstracts in English

7 (Records 1-7 displayed on this page)
  • 1