Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 21

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Analysis of maximum voltage transient of JT-60SA toroidal field coils in case of fast discharge

Novello, L.*; Cara, P.*; Coletti, A.*; Gaio, E.*; Maistrello, A.*; Matsukawa, Makoto; Philipps, G.*; Tomarchio, V.*; Yamauchi, Kunihito

IEEE Transactions on Applied Superconductivity, 26(2), p.4700507_1 - 4700507_7, 2016/03

 Times Cited Count:7 Percentile:39.48(Engineering, Electrical & Electronic)

Journal Articles

The Roles of plasma rotation and toroidal field ripple on the H-mode pedestal structure in JT-60U

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

Plasma Physics and Controlled Fusion, 48(5A), p.A193 - A199, 2006/05

 Times Cited Count:10 Percentile:34.1(Physics, Fluids & Plasmas)

The characteristics of the H-mode pedestal structure were investigated by conducting the power scans for a variation of the toroidal momentum sources at different toroidal field ripple in JT-60U. It was found that the pedestal pressure is increased by reduced loss power of fast ions, independently of toroidal rotation. However, the energy confinement is improved with the CO-directed toroidal momentum source at H-mode plasmas with small ripple loss.

Journal Articles

Stabilization mechanism of ballooning modes by toroidal rotation shear in tokamaks

Furukawa, Masaru; Tokuda, Shinji

Nuclear Fusion, 45(5), p.377 - 383, 2005/05

 Times Cited Count:10 Percentile:33.97(Physics, Fluids & Plasmas)

A ballooning perturbation in a toroidally rotating tokamak is expanded by square-integrable eigenfunctions of an eigenvalue problem associated with ballooning modes in a static plasma. Especially a weight function is chosen such that the eigenvalue problem has only the discrete spectrum. The eigenvalues evolve in time owing to toroidal rotation shear, resulting in countably infinite number of crossings among them. The crossings cause energy transfer from an unstable mode to the infinite number of stable modes; such transfer works as the stabilization mechanism of the ballooning mode. A simple analytic formula is derived for estimating the toroidal rotation shear required to stabilize the ballooning mode.

Journal Articles

Mechanism of stabilization of ballooning modes by toroidal rotation shear in tokamaks

Furukawa, Masaru; Tokuda, Shinji

Physical Review Letters, 94(17), p.175001_1 - 175001_4, 2005/05

 Times Cited Count:18 Percentile:66.53(Physics, Multidisciplinary)

A ballooning perturbation in a toroidally rotating tokamaks is expanded by square-integrable eigenfunctions of an eigenvalue problem associated with ballooning modes in a static plasma. Especially a weight function is chosen such that the eigenvalue problem has only the discrete spectrum. The eigenvalues evolve in time owing to toroidal rotation shear, resulting in countably infinite number of crossings among them. The crossings cause energy transfer from an unstable mode to the infinite number of stable modes; such transfer works as the stabilization mechanism of the ballooning mode.

Journal Articles

First principles based simulations of instabilities and turbulence

Villard, L.*; Angelino, P.*; Bottino, A.*; Allfrey, S. J.*; Hatzky, R.*; Idomura, Yasuhiro; Sauter, O.*; Tran, T. M.*

Plasma Physics and Controlled Fusion, 46(12B), p.B51 - B62, 2004/12

 Times Cited Count:29 Percentile:66.92(Physics, Fluids & Plasmas)

This paper reviews the present status of recent first principles based plasma turbulence simulations, and gives quantitative discussions on influences of the v// nonlinearlity and the geometry effects in the gyrokinetic Poisson equaiton, which are ignored in the conventional approximations, on simulations results. Careful treatments of these effects enable turbulence simulations satisfying the conservation of the energy and the particle number. The new simulation disclosed new phenomena, and it is found that (1) turbulence spreading is induced by avalanche like phnemena consisting of bursty heat transport and local flattening of pressure profiles, and (2) nonlinearly driven E$$times$$B flows become global shear flows with scale lengths of about 30 ion gyro radii.

Journal Articles

Stability of ideal MHD ballooning modes and its stabilization by toroidal rotation shear near separatrix

Furukawa, Masaru; Tokuda, Shinji; Wakatani, Masahiro*

Plasma Physics and Controlled Fusion, 46(2), p.409 - 421, 2004/02

 Times Cited Count:7 Percentile:22.88(Physics, Fluids & Plasmas)

In the H-mode (high-confinement mode) pedestal region of a static or a toroidally rotating D-shaped tokamak plasma, the separatrix or the X-point affects the high-n ballooning stability (n: toroidal mode number) only in a thin layer in the pedestal region. Therefore, D-shaping effectively stabilizes the ballooning modes even for a toroidally rotating plasma with a separatrix.

Journal Articles

A Model equation for ballooning modes in toroidally rotating tokamaks

Furukawa, Masaru; Tokuda, Shinji

Journal of Plasma and Fusion Research SERIES, Vol.6, p.210 - 213, 2004/00

A model equation for ballooning modes in toroidally rotating tokamaks is derived. It is confirmed that the model equation is appropriate for analyzing the stabilization mechanism of the ballooning modes by comparing the numerical solutions of the model equation with those of the original ballooning equations.

Journal Articles

Current point formation and magnetic reconnection process in nonlinearly destabilized double tearing modes

Ishii, Yasutomo; Azumi, Masafumi; Kishimoto, Yasuaki

Physics of Plasmas, 10(9), p.3512 - 3520, 2003/09

 Times Cited Count:12 Percentile:36.95(Physics, Fluids & Plasmas)

no abstracts in English

Journal Articles

Geometrical improvements of rotational stabilization of high-$$n$$ ballooning modes in tokamaks

Furukawa, Masaru; Tokuda, Shinji; Wakatani, Masahiro*

Nuclear Fusion, 43(6), p.425 - 429, 2003/06

We have found numerically that damping phases appear in the time evolution of the perturbation energy of high-$$n$$ ballooning modes in the presence of toroidal shear flows. The damping dominates exponential growth which occurs in the bad curvature region, resulting in stabilization of ballooning modes. D-shaping of plasma cross-section, reduction of aspect ratio, and arrangement of X-point at inner side of the torus enhance the stabilization effect of the toroidal flow through this mechanism.

Journal Articles

Geometrical improvements of rotational stabilization of high-$$n$$ ballooning modes in tokamaks

Furukawa, Masaru; Tokuda, Shinji; Wakatani, Masahiro*

Nuclear Fusion, 43(6), p.425 - 429, 2003/06

 Times Cited Count:10 Percentile:31.59(Physics, Fluids & Plasmas)

We have found numerically that damping phases appear in the time evolution of the perturbation energy of high-$$n$$ ballooning modes in the presence of toriodal flow shear, where n is a toroidal mode number. The damping dominates exponential growth which occurs in the bad curvature region, resulting in stabilization of ballooning modes. D-shaping of plasma cross-section, reduction of aspect ratio, and arrangement of an X-point at inner side of the torus enhance the stabilization effect of the toroidal flow shear through this mechanism.

Journal Articles

Coherent magnetic fluctuations ergodized ELMy H-mode in the JFT-2M tokamak

W.Liu*; Miura, Yukitoshi; JFT-2M Group

Purazuma, Kaku Yugo Gakkai-Shi, 74(7), p.753 - 757, 1998/07

no abstracts in English

Journal Articles

Poloidal shear flow effect on toroidal ion temperature gradient mode; A Theory and simulation

J.Y.Kim*; Kishimoto, Yasuaki; Wakatani, Masahiro*; Tajima, Toshiki*

Physics of Plasmas, 3(10), p.3689 - 3695, 1996/10

 Times Cited Count:52 Percentile:82.07(Physics, Fluids & Plasmas)

no abstracts in English

Journal Articles

Characteristic peaked profiles of ion temperature and toroidal rotation velocity in JT-60 hot ion modes

Koide, Yoshihiko; Ishida, Shinichi; Sakasai, Akira; Shirai, Hiroshi; Hirayama, Toshio; Kubo, Hirotaka; Sugie, Tatsuo;

Nuclear Fusion, 33(2), p.251 - 261, 1993/00

 Times Cited Count:13 Percentile:45.65(Physics, Fluids & Plasmas)

no abstracts in English

JAEA Reports

Characteristics of Pellet and Neutral-Beam Injected Single Null Divertor Discharges of the JFT-2M Tokamak

; ; Sengoku, Seio; ; ; *; ; ; ; ; et al.

JAERI-M 86-148, 18 Pages, 1986/09

JAERI-M-86-148.pdf:0.57MB

no abstracts in English

Journal Articles

Kinetic theory of global n=1 instabilities in toroidal plasmas

; *; ;

Journal of the Physical Society of Japan, 53(5), p.1759 - 1774, 1984/00

 Times Cited Count:2 Percentile:34.43(Physics, Multidisciplinary)

no abstracts in English

JAEA Reports

MHD Stability Analyses of a Tokamak Plasma by Time-Dependent Codes

JAERI-M 82-093, 56 Pages, 1982/07

JAERI-M-82-093.pdf:2.28MB

no abstracts in English

JAEA Reports

Matrix method for kinetic ballooning mode

; ; ; *

JAERI-M 82-080, 18 Pages, 1982/07

JAERI-M-82-080.pdf:0.52MB

no abstracts in English

Journal Articles

Kinetic theory of electromagnetic high-n ballooning instabilities

; *; ;

Nuclear Fusion, 22(8), p.1031 - 1047, 1982/00

 Times Cited Count:10 Percentile:41(Physics, Fluids & Plasmas)

no abstracts in English

JAEA Reports

Internal Disruption in High $$beta$$$$_{p}$$ Tokamak

; ; ; Tsunematsu, Toshihide; ; ; ; *; Takeda, Tatsuoki

JAERI-M 9787, 25 Pages, 1981/11

JAERI-M-9787.pdf:0.79MB

no abstracts in English

Journal Articles

Kinetic theory of nonlocal high-n ballooning mode

; *;

Journal of the Physical Society of Japan, 50(2), p.655 - 658, 1981/00

 Times Cited Count:6 Percentile:53.82(Physics, Multidisciplinary)

no abstracts in English

Journal Articles

Toroidal effects on nonlocal collisionless drift instability

; ; *

Journal of the Physical Society of Japan, 48(1), p.258 - 263, 1980/00

 Times Cited Count:7 Percentile:55.55(Physics, Multidisciplinary)

no abstracts in English

21 (Records 1-20 displayed on this page)