Turbulent transport reduction induced by transition on radial electric field shear and curvature through amplitude and cross-phase in torus plasma

T. Kobayashi, K. Itoh, T. Ido, K. Kamiya, Sanae Itoh, Y. Miura, Yoshihiko Nagashima, akihide fujisawa, Inagaki Shigeru, K. Ida

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

Spatiotemporal evolutions of radial electric field and turbulence are measured simultaneously in the H-mode transition, which is a prototypical example of turbulence structure formation in higherature plasmas. In the dynamical phase where transport barrier is established abruptly, the time-space-frequency-resolved turbulent particle flux is obtained. Here we report the validation of the mechanism of transport barrier formation quantitatively. It is found that the particle flux is suppressed predominantly by reducing density fluctuation amplitude and cross phase between density fluctuation and potential fluctuation. Both radial electric field shear and curvature are responsible for the amplitude suppression as was predicted by theory. Turbulence amplitude reduction immediately responds to the growth of the radial electric field non-uniformity and saturates, while cross phase continuously approaches zero.

Original languageEnglish
Article number14971
JournalScientific reports
Volume7
Issue number1
DOIs
Publication statusPublished - Dec 1 2017

Fingerprint

turbulence
curvature
shear
flux (rate)
electric fields
nonuniformity
retarding

All Science Journal Classification (ASJC) codes

  • General

Cite this

Turbulent transport reduction induced by transition on radial electric field shear and curvature through amplitude and cross-phase in torus plasma. / Kobayashi, T.; Itoh, K.; Ido, T.; Kamiya, K.; Itoh, Sanae; Miura, Y.; Nagashima, Yoshihiko; fujisawa, akihide; Shigeru, Inagaki; Ida, K.

In: Scientific reports, Vol. 7, No. 1, 14971, 01.12.2017.

Research output: Contribution to journalArticle

@article{a38301206fd24c4a9df02e1de764984c,
title = "Turbulent transport reduction induced by transition on radial electric field shear and curvature through amplitude and cross-phase in torus plasma",
abstract = "Spatiotemporal evolutions of radial electric field and turbulence are measured simultaneously in the H-mode transition, which is a prototypical example of turbulence structure formation in higherature plasmas. In the dynamical phase where transport barrier is established abruptly, the time-space-frequency-resolved turbulent particle flux is obtained. Here we report the validation of the mechanism of transport barrier formation quantitatively. It is found that the particle flux is suppressed predominantly by reducing density fluctuation amplitude and cross phase between density fluctuation and potential fluctuation. Both radial electric field shear and curvature are responsible for the amplitude suppression as was predicted by theory. Turbulence amplitude reduction immediately responds to the growth of the radial electric field non-uniformity and saturates, while cross phase continuously approaches zero.",
author = "T. Kobayashi and K. Itoh and T. Ido and K. Kamiya and Sanae Itoh and Y. Miura and Yoshihiko Nagashima and akihide fujisawa and Inagaki Shigeru and K. Ida",
year = "2017",
month = "12",
day = "1",
doi = "10.1038/s41598-017-14821-y",
language = "English",
volume = "7",
journal = "Scientific Reports",
issn = "2045-2322",
publisher = "Nature Publishing Group",
number = "1",

}

TY - JOUR

T1 - Turbulent transport reduction induced by transition on radial electric field shear and curvature through amplitude and cross-phase in torus plasma

AU - Kobayashi, T.

AU - Itoh, K.

AU - Ido, T.

AU - Kamiya, K.

AU - Itoh, Sanae

AU - Miura, Y.

AU - Nagashima, Yoshihiko

AU - fujisawa, akihide

AU - Shigeru, Inagaki

AU - Ida, K.

PY - 2017/12/1

Y1 - 2017/12/1

N2 - Spatiotemporal evolutions of radial electric field and turbulence are measured simultaneously in the H-mode transition, which is a prototypical example of turbulence structure formation in higherature plasmas. In the dynamical phase where transport barrier is established abruptly, the time-space-frequency-resolved turbulent particle flux is obtained. Here we report the validation of the mechanism of transport barrier formation quantitatively. It is found that the particle flux is suppressed predominantly by reducing density fluctuation amplitude and cross phase between density fluctuation and potential fluctuation. Both radial electric field shear and curvature are responsible for the amplitude suppression as was predicted by theory. Turbulence amplitude reduction immediately responds to the growth of the radial electric field non-uniformity and saturates, while cross phase continuously approaches zero.

AB - Spatiotemporal evolutions of radial electric field and turbulence are measured simultaneously in the H-mode transition, which is a prototypical example of turbulence structure formation in higherature plasmas. In the dynamical phase where transport barrier is established abruptly, the time-space-frequency-resolved turbulent particle flux is obtained. Here we report the validation of the mechanism of transport barrier formation quantitatively. It is found that the particle flux is suppressed predominantly by reducing density fluctuation amplitude and cross phase between density fluctuation and potential fluctuation. Both radial electric field shear and curvature are responsible for the amplitude suppression as was predicted by theory. Turbulence amplitude reduction immediately responds to the growth of the radial electric field non-uniformity and saturates, while cross phase continuously approaches zero.

UR - http://www.scopus.com/inward/record.url?scp=85032821551&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85032821551&partnerID=8YFLogxK

U2 - 10.1038/s41598-017-14821-y

DO - 10.1038/s41598-017-14821-y

M3 - Article

VL - 7

JO - Scientific Reports

JF - Scientific Reports

SN - 2045-2322

IS - 1

M1 - 14971

ER -