Nonlinear Dynamo in Obliquely Rotating Stratified Electroconductive Fluid in an Uniformly Magnetic Field
In this paper, we investigated a new large-scale instability that arises in an obliquely rotating convective electrically conducting fluid in an external uniform magnetic field with a small-scale external force with zero helicity. This force excites small-scale velocity oscillations with a small Rey...
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| Format: | Article |
| Language: | English |
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V.N. Karazin Kharkiv National University Publishing
2020-02-01
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| Series: | East European Journal of Physics |
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| Online Access: | https://periodicals.karazin.ua/eejp/article/view/15444 |
| _version_ | 1818108969358458880 |
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| author | Michael I. Kopp Anatoly V. Tur Konstantin N. Kulik Volodymyr V. Yanovsky |
| author_facet | Michael I. Kopp Anatoly V. Tur Konstantin N. Kulik Volodymyr V. Yanovsky |
| author_sort | Michael I. Kopp |
| collection | DOAJ |
| description | In this paper, we investigated a new large-scale instability that arises in an obliquely rotating convective electrically conducting fluid in an external uniform magnetic field with a small-scale external force with zero helicity. This force excites small-scale velocity oscillations with a small Reynolds number. Using the method of multiscale asymptotic expansions, we obtain the nonlinear equations for vortex and magnetic disturbances in the third order of the Reynolds number. It is shown that the combined effects of the Coriolis force and the small external forces in a rotating conducting fluid possible large-scale instability. The linear stage of the magneto-vortex dynamo arising as a result of instabilities of -effect type is investigated. The mechanism of amplification of large-scale vortex disturbances due to the development of the hydrodynamic - effect taking into account the temperature stratification of the medium is studied. It was shown that a «weak» external magnetic field contributes to the generation of large-scale vortex and magnetic perturbations, while a «strong» external magnetic field suppresses the generation of magnetic-vortex perturbations. Numerical methods have been used to find stationary solutions of the equations of a nonlinear magneto-vortex dynamo in the form of localized chaotic structures in two cases when there is no external uniform magnetic field and when it is present. |
| first_indexed | 2024-12-11T02:23:48Z |
| format | Article |
| id | doaj.art-e3db44fe2ea840f48d312ef44156ae9b |
| institution | Directory Open Access Journal |
| issn | 2312-4334 2312-4539 |
| language | English |
| last_indexed | 2024-12-11T02:23:48Z |
| publishDate | 2020-02-01 |
| publisher | V.N. Karazin Kharkiv National University Publishing |
| record_format | Article |
| series | East European Journal of Physics |
| spelling | doaj.art-e3db44fe2ea840f48d312ef44156ae9b2022-12-22T01:24:00ZengV.N. Karazin Kharkiv National University PublishingEast European Journal of Physics2312-43342312-45392020-02-01153610.26565/2312-4334-2020-1-0115444Nonlinear Dynamo in Obliquely Rotating Stratified Electroconductive Fluid in an Uniformly Magnetic FieldMichael I. Kopp0Anatoly V. Tur1Konstantin N. Kulik2Volodymyr V. Yanovsky3Institute for Single Cristals, Nat. Academy of Science Ukraine, Kharkiv, UkraineUniversite Toulouse [UPS], CNRS, Institute of Research for Astrophysics and Planetology, Toulouse, FranceInstitute for Single Cristals, Nat. Academy of Science Ukraine, Kharkiv,UkraineInstitute for Single Cristals, Nat. Academy of Science Ukraine, Kharkiv, Ukraine; V.N. Karazin Kharkiv National University, Kharkiv, UkraineIn this paper, we investigated a new large-scale instability that arises in an obliquely rotating convective electrically conducting fluid in an external uniform magnetic field with a small-scale external force with zero helicity. This force excites small-scale velocity oscillations with a small Reynolds number. Using the method of multiscale asymptotic expansions, we obtain the nonlinear equations for vortex and magnetic disturbances in the third order of the Reynolds number. It is shown that the combined effects of the Coriolis force and the small external forces in a rotating conducting fluid possible large-scale instability. The linear stage of the magneto-vortex dynamo arising as a result of instabilities of -effect type is investigated. The mechanism of amplification of large-scale vortex disturbances due to the development of the hydrodynamic - effect taking into account the temperature stratification of the medium is studied. It was shown that a «weak» external magnetic field contributes to the generation of large-scale vortex and magnetic perturbations, while a «strong» external magnetic field suppresses the generation of magnetic-vortex perturbations. Numerical methods have been used to find stationary solutions of the equations of a nonlinear magneto-vortex dynamo in the form of localized chaotic structures in two cases when there is no external uniform magnetic field and when it is present.https://periodicals.karazin.ua/eejp/article/view/15444magnetic hydrodynamicsboussinesq approximationcoriolis forcemulti-scale asymptotic expansionsnon-helical turbulence |
| spellingShingle | Michael I. Kopp Anatoly V. Tur Konstantin N. Kulik Volodymyr V. Yanovsky Nonlinear Dynamo in Obliquely Rotating Stratified Electroconductive Fluid in an Uniformly Magnetic Field East European Journal of Physics magnetic hydrodynamics boussinesq approximation coriolis force multi-scale asymptotic expansions non-helical turbulence |
| title | Nonlinear Dynamo in Obliquely Rotating Stratified Electroconductive Fluid in an Uniformly Magnetic Field |
| title_full | Nonlinear Dynamo in Obliquely Rotating Stratified Electroconductive Fluid in an Uniformly Magnetic Field |
| title_fullStr | Nonlinear Dynamo in Obliquely Rotating Stratified Electroconductive Fluid in an Uniformly Magnetic Field |
| title_full_unstemmed | Nonlinear Dynamo in Obliquely Rotating Stratified Electroconductive Fluid in an Uniformly Magnetic Field |
| title_short | Nonlinear Dynamo in Obliquely Rotating Stratified Electroconductive Fluid in an Uniformly Magnetic Field |
| title_sort | nonlinear dynamo in obliquely rotating stratified electroconductive fluid in an uniformly magnetic field |
| topic | magnetic hydrodynamics boussinesq approximation coriolis force multi-scale asymptotic expansions non-helical turbulence |
| url | https://periodicals.karazin.ua/eejp/article/view/15444 |
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