Vestnik KRAUNC. Fiz.-Mat. Nauki. 2022. vol. 41. no. 4. pp. 107–119. ISSN 2079-6641
Dynamics of generation modes changes in magnetic field depending on the oscillation frequency of the \alpha -effect suppression process by field energy in the \alpha\Omega -dynamo model
O. V. Sheremetyeva
Institute of Cosmophysical Research and Radio Wave Propagation, FEB RAS, 684034 Kamchatka region, Elizovskiy district, Paratunka, Mirnaya str., 7, Russia
This article considers a \alpha\Omega -dynamo large-scale model in a low-mode approximation. The intensity of the \alpha -effect is regulated by a process with hereditarity properties, depending on the energy of the magnetic field. The nature of the process impact is determined by an alternating kernel function with a variable damping frequency and a constant damping coefficient equal to 0.1. Based on the results of numerical simulation of the magnetic field generation modes, the boundaries for the values of the model parameters are determined for which there are no oscillations in the velocity field of a viscous liquid or they are insignificant. The results of magnetic field generation modes simulation at various damping frequency values are displayed on the phase plane of the control parameters. These parameters contain information about large-scale and turbulent generators. The paper investigates the question about the dynamics of changes in the pattern on the phase plane depending on the value of the damping frequency and the waiting time. A comparison is made with the results obtained earlier for the constant intensity of the \alpha -effect and for the intensity, the change of which is determined by the process with exponential kernel.
Key words: low-mode dynamo model, \alpha\Omega -dynamo, \alpha -effect, magnetic field, reversals.
Original article submitted: 29.11.2022
Revision submitted: 06.12.2022
For citation. Sheremetyeva O. V. Dynamics of generation modes changes in magnetic field depending on the oscillation frequency of the \alpha -effect suppression process by field energy in the \alpha\Omega -dynamo model. Vestnik KRAUNC. Fiz.-mat. nauki. 2022, 41: 4, 107-119. DOI: 10.26117/2079-6641-2022-41-4-107-119
Competing interests. The author declare that there is no conflicts of interest regarding authorship and publication.
Contribution and Responsibility. The author is solely responsible for providing the final version of the article in print. The final version of the manuscript was approved by the author.
The content is published under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/deed.ru)
© Sheremetyeva O. V., 2022
Funding. The work was carried out within the framework of the state assignment on the topic Physical processes in the system of near space and geospheres under solar and lithospheric influences (No. AAAA-A21-121011290003-0).
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Sheremetyeva Olga Vladimirovna – PhD (Tech.), Research Scientist, Laboratory of Physical Process Modeling, Institute of Cosmophysical Research and Radio Wave Propagation FEB RAS, Paratunka, Kamchatka, Russia, ORCID 0000-0001-9417-9731.