### Abstract

The probability distribution function (PDF) tails of the zonal flow structure formation and the PDF tails of momentum flux are computed by incorporating the effect of a shear flow in ion-temperature-gradient (ITG) turbulence. The bipolar vortex soliton (modon) is assumed to be the coherent structure responsible for bursty and intermittent events driving the PDF tails. It is found that stronger zonal flows are generated in ITG turbulence than Hasegawa-Mima turbulence, as well as further from marginal stability. This suggests that although ITG turbulence has a higher level of heat flux, it also more likely generates stronger zonal flows, leading to a self-regulating system. It is also shown that shear flows can significantly reduce the PDF tails of Reynolds stress and structure formation.

Original language | English |
---|---|

Article number | 082312 |

Journal | Physics of Plasmas |

Volume | 15 |

Issue number | 8 |

DOIs | |

Publication status | Published - 8 Sep 2008 |

Externally published | Yes |

### Fingerprint

### ASJC Scopus subject areas

- Physics and Astronomy(all)
- Condensed Matter Physics

### Cite this

*Physics of Plasmas*,

*15*(8), [082312]. https://doi.org/10.1063/1.2973177

**Analytical theory of the probability distribution function of structure formation.** / Anderson, Johan; Kim, Eun Jin.

Research output: Contribution to journal › Article

*Physics of Plasmas*, vol. 15, no. 8, 082312. https://doi.org/10.1063/1.2973177

}

TY - JOUR

T1 - Analytical theory of the probability distribution function of structure formation

AU - Anderson, Johan

AU - Kim, Eun Jin

PY - 2008/9/8

Y1 - 2008/9/8

N2 - The probability distribution function (PDF) tails of the zonal flow structure formation and the PDF tails of momentum flux are computed by incorporating the effect of a shear flow in ion-temperature-gradient (ITG) turbulence. The bipolar vortex soliton (modon) is assumed to be the coherent structure responsible for bursty and intermittent events driving the PDF tails. It is found that stronger zonal flows are generated in ITG turbulence than Hasegawa-Mima turbulence, as well as further from marginal stability. This suggests that although ITG turbulence has a higher level of heat flux, it also more likely generates stronger zonal flows, leading to a self-regulating system. It is also shown that shear flows can significantly reduce the PDF tails of Reynolds stress and structure formation.

AB - The probability distribution function (PDF) tails of the zonal flow structure formation and the PDF tails of momentum flux are computed by incorporating the effect of a shear flow in ion-temperature-gradient (ITG) turbulence. The bipolar vortex soliton (modon) is assumed to be the coherent structure responsible for bursty and intermittent events driving the PDF tails. It is found that stronger zonal flows are generated in ITG turbulence than Hasegawa-Mima turbulence, as well as further from marginal stability. This suggests that although ITG turbulence has a higher level of heat flux, it also more likely generates stronger zonal flows, leading to a self-regulating system. It is also shown that shear flows can significantly reduce the PDF tails of Reynolds stress and structure formation.

UR - http://www.scopus.com/inward/record.url?scp=50849124434&partnerID=8YFLogxK

U2 - 10.1063/1.2973177

DO - 10.1063/1.2973177

M3 - Article

VL - 15

JO - Physics of Plasmas

JF - Physics of Plasmas

SN - 1070-664X

IS - 8

M1 - 082312

ER -