Scale variability in convection-driven MHD dynamos at low Ekman number

Futoshi Takahashi, Masaki Matsushima, Yoshimori Honkura

研究成果: ジャーナルへの寄稿記事

50 引用 (Scopus)

抄録

We have undertaken a numerical study of convection-driven MHD dynamos in a rapidly rotating spherical shell with the Ekman number, E, down to 2 × 1 0- 6 and the magnetic Prandtl number, Pm, down to 0.2. We focus on the characteristic scales of the flow and the magnetic field. Smaller-scale convection vortices responsible for generating the magnetic field appear at lower Ekman numbers, while the scale of the magnetic field shows less variation compared with the flow. As a result, scale separation between the flow and the magnetic field occurs as the Ekman number is decreased. Scale separation helps dynamos to maintain the magnetic field at P m < 1 through increase in the effective value of the magnetic Reynolds number.

元の言語英語
ページ(範囲)168-178
ページ数11
ジャーナルPhysics of the Earth and Planetary Interiors
167
発行部数3-4
DOI
出版物ステータス出版済み - 4 1 2008

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rotating generators
convection
magnetic field
magnetic fields
spherical shells
Prandtl number
Reynolds number
vortex
vortices
shell

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Geophysics
  • Physics and Astronomy (miscellaneous)
  • Space and Planetary Science

これを引用

Scale variability in convection-driven MHD dynamos at low Ekman number. / Takahashi, Futoshi; Matsushima, Masaki; Honkura, Yoshimori.

:: Physics of the Earth and Planetary Interiors, 巻 167, 番号 3-4, 01.04.2008, p. 168-178.

研究成果: ジャーナルへの寄稿記事

Takahashi, Futoshi ; Matsushima, Masaki ; Honkura, Yoshimori. / Scale variability in convection-driven MHD dynamos at low Ekman number. :: Physics of the Earth and Planetary Interiors. 2008 ; 巻 167, 番号 3-4. pp. 168-178.
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