scholarly journals DEPENDENCE OF THE MAGNETIC FIELD GENERATION MODELS OF IN MODEL OF A αΩ-DYNAMO ON THE INTENSITY OF A POWER TYPE α GENERATOR

2019 ◽  
pp. 58-66
Author(s):  
А.Н. Годомская ◽  
О.В. Шереметьева
Keyword(s):  
Magnetic Field ◽  
Comparative Analysis ◽  
Velocity Field ◽  
Dynamic Model ◽  
Radial Component ◽  
Magnetic Field Generation ◽  
Power Type ◽  
Exponential Kernel ◽  
Field Generation ◽  
The Magnetic Field

В динамической модели -динамо с переменной интенсивностью -генератора моделируются инверсии магнитного поля. Изменение интенсивности -генератора как следствие синхронизации высших мод поля скоростей и магнитного поля регулируется функцией Z(t) со степенным ядром. Получены режимы динамо для двух видов радиальной составляющей в скалярной параметризации -эффекта. Проведён анализ результатов в зависимости от изменения показателя степени ядра функции Z(t), а также сравнительный анализ с результатами исследования 10, где использовано показательное ядро функциии Z(t). In the dynamic model -dimensions are simulated reversions of the magnetic field with a varying intensity of the -generator. The change of the -generator intensity as a result of synchronization of higher modes of the velocity field and the magnetic field is regulated by a function Z(t) with a power kernel. Dynamo modes are obtained for two types of radial component in the scalar parameterization of the -effect. The results were analyzed depending on the change in the exponent of the kernel of the function Z(t), also a comparative analysis with the results of the study 10, where the exponential kernel of the function Z(t) was used.

scholarly journals Modes of magnetic field generation in models of a αΩ-dynamo with a power type α-generator

2019 ◽  
Vol 127 ◽  
pp. 02016 ◽  
Author(s):  
Anna Godomskaya ◽  
Olga Sheremetyeva
Keyword(s):  
Magnetic Field ◽  
Comparative Analysis ◽  
Velocity Field ◽  
Dynamic Model ◽  
Radial Component ◽  
Magnetic Field Generation ◽  
Power Type ◽  
Exponential Kernel ◽  
Field Generation ◽  
The Magnetic Field

In the dynamic model αΩ-dimensions are simulated reversions of the magnetic field with a varying intensity of the α-generator. The change of the α-generator intensity as a result of synchronization of higher modes of the velocity field and the magnetic field is regulated by a function Z(t) with a power kernel. Dynamo modes are obtained for two types of radial component in the scalar parameterization of the α-effect. The results were analyzed depending on the change in the exponent of the kernel of the function Z(t) and the type of the power kernel, also a comparative analysis with the results of the study [9], where the exponential kernel of the function Z(t) was used.

scholarly journals Temporal regularities of changing magnetic field generation modes in the model of the αΩ-dynamo

2020 ◽  
Vol 196 ◽  
pp. 02030
Author(s):  
Olga Sheremetyeva ◽  
Anna Godomskaya
Keyword(s):  
Magnetic Field ◽  
Velocity Field ◽  
Waiting Time ◽  
Delay Time ◽  
Magnetic Field Generation ◽  
Temporal Characteristics ◽  
Field Generation ◽  
Exponential Power ◽  
External Forces ◽  
The Magnetic Field

In the dynamic model aΩ-dynamo the change in the intensity of the a-generator under the action of external forces is considered as a result of synchroniza-tion of higher modes of the velocity field and the magnetic field and is regulated by the function Z(t) with an exponential-power kernel J(t). Depending on the choice of the exponent and the scale factor of the kernel determine its temporal characteristics: delay time and waiting time. The question of changing the modes of magnetic field generation depending on the temporal characteristics of the function’s kernel is investigating. In the dynamic model aΩ-dynamo the change of the a-generator intensity under the action of external forces is considered as a result of synchronization of higher modes of the velocity field and the magnetic field and is regulated by the function Z(t) with an exponential-power kernel J(t). Depending on the choice of the exponent and the scale factor of the kernel J(t) determine its temporal characteristics: delay time and waiting time. The question of changing the modes of magnetic field generation depending on the temporal characteristics of the function’s kernel is investigating.

scholarly journals Reversals in the low-mode model dynamo with αΩ-generators

2018 ◽  
Vol 62 ◽  
pp. 02016 ◽  
Author(s):  
Anna Godomskaya ◽  
Olga Sheremetyeva
Keyword(s):  
Magnetic Field ◽  
Velocity Field ◽  
Dynamic Model ◽  
The Magnetic Field

In the dynamic model αΩ-dimensions are simulated reversions of the magnetic field with a varying intensity of the α-generator. We consider such changes in intensity as a consequence of the synchronization of the higher discarded modes of the velocity field and the magnetic field. Dynamo regimes are studied depending on the change in the intensity of the generator.

Simulation studies of the magnetic field generation in cosmological plasmas

2004 ◽  
Vol 330 (5) ◽  
pp. 384-389 ◽  
Author(s):  
Jun-Ichi Sakai ◽  
Reinhard Schlickeiser ◽  
P.K. Shukla
Keyword(s):  
Magnetic Field ◽  
Simulation Studies ◽  
Magnetic Field Generation ◽  
Field Generation ◽  
The Magnetic Field

scholarly journals Generation of strong magnetic fields with a laser-driven coil

2018 ◽  
Vol 6 ◽  
Author(s):  
Zhe Zhang ◽  
Baojun Zhu ◽  
Yutong Li ◽  
Weiman Jiang ◽  
Dawei Yuan ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Experimental Studies ◽  
Diagnostic Techniques ◽  
Magnetic Field Generation ◽  
Field Generation ◽  
Research Fields ◽  
Laser Facility ◽  
Spatio Temporal ◽  
The Magnetic Field

As a promising new way to generate a controllable strong magnetic field, laser-driven magnetic coils have attracted interest in many research fields. In 2013, a kilotesla level magnetic field was achieved at the Gekko XII laser facility with a capacitor–coil target. A similar approach has been adopted in a number of laboratories, with a variety of targets of different shapes. The peak strength of the magnetic field varies from a few tesla to kilotesla, with different spatio-temporal ranges. The differences are determined by the target geometry and the parameters of the incident laser. Here we present a review of the results of recent experimental studies of laser-driven magnetic field generation, as well as a discussion of the diagnostic techniques required for such rapidly changing magnetic fields. As an extension of the magnetic field generation, some applications are discussed.

scholarly journals The effect of velocity shear on dynamo action due to rotating convection

2013 ◽  
Vol 717 ◽  
pp. 395-416 ◽  
Author(s):  
D. W. Hughes ◽  
M. R. E. Proctor
Keyword(s):  
Magnetic Field ◽  
Velocity Field ◽  
Large Scale ◽  
Mean Field ◽  
Magnetic Reynolds Number ◽  
Velocity Shear ◽  
Magnetic Field Generation ◽  
Dynamo Action ◽  
Rotating Convection ◽  
The Magnetic Field

AbstractRecent numerical simulations of dynamo action resulting from rotating convection have revealed some serious problems in applying the standard picture of mean field electrodynamics at high values of the magnetic Reynolds number, and have thereby underlined the difficulties in large-scale magnetic field generation in this regime. Here we consider kinematic dynamo processes in a rotating convective layer of Boussinesq fluid with the additional influence of a large-scale horizontal velocity shear. Incorporating the shear flow enhances the dynamo growth rate and also leads to the generation of significant magnetic fields on large scales. By the technique of spectral filtering, we analyse the modes in the velocity that are principally responsible for dynamo action, and show that the magnetic field resulting from the full flow relies crucially on a range of scales in the velocity field. Filtering the flow to provide a true separation of scales between the shear and the convective flow also leads to dynamo action; however, the magnetic field in this case has a very different structure from that generated by the full velocity field. We also show that the nature of the dynamo action is broadly similar irrespective of whether the flow in the absence of shear can support dynamo action.

scholarly journals Generation of the Seed Magnetic Field

1993 ◽  
Vol 157 ◽  
pp. 421-425
Author(s):  
A. Lazarian
Keyword(s):  
Magnetic Field ◽  
Molecular Clouds ◽  
The Other ◽  
Small Scale ◽  
Magnetic Field Generation ◽  
Average Value ◽  
Field Generation ◽  
Seed Field ◽  
Direct Generation ◽  
The Magnetic Field

Two mechanisms of the galactic seed field generation are discussed. One of the mechanisms implies a direct generation of the seed magnetic field through a battery process (Lazarian 1992a). The other accounts for the possibility of the preliminary amplification of the magnetic field on a scale of molecular clouds (Lazarian 1992b). This means that the galactic dynamo can feed on the non-zero average value of the magnetic field amplified by such a small-scale dynamo. It is shown that both mechanisms can generate an adequate seed field. These two scenarios of the seed magnetic field generation can be distinguished by an analysis of the present day galactic magnetic structure.

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