Recent results on heliotron E

Uo, K.; Iiyoshi, A.; Obiki, T.; Motojima, O.; Morimoto, S.; Sasaki, Akihiko; Kondo, K.; Sato, Motoyasu; Mutoh, T.; Zushi, H.; Kaneko, Hiroshi; Besshou, S.; Sano, F.; Mizuuchi, T.; Sudo, S.; Hanatani, K.; Nakasuga, M.; Ohtake, I.; Iima, M.; Nakashima, Y.; Nishino, Norikazu

doi:10.1016/0167-5087(83)90232-6

Cited by 30 publications

(37 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…During the last few years, substantial progress has been made in experiments with helical systems. Special effort has been concentrated on currentless plasma production [1][2][3][4][5][6][7] and subsequent heating of such a plasma. The energy confinement times essentially follow a drift parameter scaling for Joule-heated discharges.…”

Section: Introductionmentioning

confidence: 99%

“…The final objective of the Heliotron E experiment is to produce a high-energy currentless plasma, which will lead to the demonstration that steady-state operation of a helical system is feasible. In the last three years, studies on Joule, ECRH [1,[3][4][5][6] and NBI plasmas were performed. The Joule plasma was studied as a target plasma for heating by RF and NBI.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Neutral-beam injection heating experiment on currentless plasma in the heliotron E device

Iiyoshi

Obiki

et al. 1984

Nucl. Fusion

Self Cite

View full text Add to dashboard Cite

Recent results of the neutral-beam heating experiments (NBI) on the Heliotron E plasma are reported. The target plasma for NBI is produced by electron cyclotron resonance heating (ECRH), using two gyrotrons (53.2 GHz, 200 kW X 2). The neutral beams of 2.9 MW max are injected 20 to 40 ms afterwards in order to produce a high-energy currentless plasma. At a magnetic field of 1.9 T, a maximum ion temperature of 1.0 keV is obtained at a density of 1.9 X 10 13 cm" 3 . The maximum N V E is 2.4 X 10 12 cm~3 i s. By reducing the magnetic field to 0.94 T and using the second-harmonic resonance of microwaves to produce a target plasma, a high-beta plasma is produced by NBI. The maximum central-beta and volume-average beta values are 3.6% and 2%, respectively. The paper describes the results of NBI heating experiments and the confinement and MHD activity properties of the plasmas in question.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Neutral-beam injection heating experiment on currentless plasma in the heliotron E device

Iiyoshi

Obiki

et al. 1984

Nucl. Fusion

Self Cite

View full text Add to dashboard Cite

show abstract

“…The heliotron device is characterized as the relatively week magnetic shear and hill (sometimes magnetic well) in the core and the relatively strong shear and hill in the periphery. The Heliotron-E, 3,4 the Heliotron-DR, 5 the ATF, 6 the CHS; 7 in addition to the LHD are categorized in the heliotron device. In those devices, the interchange type MHD instabilities are considered to play an important role in the confinement properties due to the magnetic hill.…”

Section: Introductionmentioning

confidence: 99%

Effect of pressure-driven MHD instabilities on confinement in reactor-relevant high-beta helical plasmas

et al. 2011

View full text Add to dashboard Cite

Through the experiment data analysis in the large helical device (LHD), the influence of the global MHD instability and the relatively short wave length MHD instabilities driven turbulence on the confinement performance in reactor-relevant high-beta helical plasmas is studied. The comparison of the energy confinement time between just before global MHD instability disappears and after that, and the estimation of the saturated mode structure by the multi-channel soft x-ray measurement enable us to quantitatively estimate the influence of the global interchange type MHD instability with different saturated mode structures on the confinement performance. According to the comparison between thermal conductivities in experiments and those predicted by theoretical transport models, the transport properties in the peripheral region of high beta LHD plasmas are quite similar with anomalous transport model based on an interchange type MHD instability driven turbulence, and that result is supported by the dependence of the density fluctuation with relatively short wave length on beta value.

show abstract

“…The calculated efficiency of the compression depends strongly on the assumed confinement scaling laws. At present, the validity of theoretical scaling laws in helical systems is unproven, and several empirical scalings have been suggested [5,6], e.g. ALCATOR-like scaling, or drift-parameter scaling.…”

mentioning

confidence: 99%

“…where <CJV>D-T> E a , C, and P ra d are the cross-section of the D-T reaction, the a-particle energy, the profile coefficient, and the radiation power density, respectively. Equations ( 4) and ( 5) yield (6) T 2 Wl/4)<aV> D . T 3 E a -P r a d 3 /n 2 3 / n 2 r 2…”

mentioning

confidence: 99%