2015年4月
Penetration of Alfven waves into an upper stably-stratified layer excited by magnetoconvection in rotating spherical shells
PHYSICS OF THE EARTH AND PLANETARY INTERIORS
- 巻
- 241
- 号
- 開始ページ
- 37
- 終了ページ
- 43
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1016/j.pepi.2015.02.005
- 出版者・発行元
- ELSEVIER SCIENCE BV
The penetration of magneto-hydrodynamic (MHD) disturbances into an upper strongly stratified stable layer excited by magnetoconvection in rotating spherical shells is investigated. An analytic expression for the penetration distance is derived by considering perturbations of a stably stratified rotating MHD Boussinesq fluid in a semi-infinite region, with the rotation axis and a uniform magnetic field tilted relative to the gravity axis. Solutions for the response to MHD disturbances applied at the bottom boundary show that the disturbances propagate as Alfven waves in the stable layer. Their propagation distance is proportional to the Alfven wave speed and inversely proportion to both the arithmetic average of viscosity and magnetic diffusion and the total wavenumber of the disturbance. The derived expression for penetration distance is in good agreement with the numerical results for neutral convection in a rotating spherical shell with an upper stably stratified layer embedded in an axially uniform basic magnetic field. (C) 2015 Elsevier B.V. All rights reserved.
- リンク情報
- ID情報
-
- DOI : 10.1016/j.pepi.2015.02.005
- ISSN : 0031-9201
- eISSN : 1872-7395
- Web of Science ID : WOS:000352679800004