Solnechno-Zemnaya Fizika Solnechno-Zemnaya Fizika Солнечно-земная физика 2712-9640 109290 10.12737/szf-114202501 Результаты исследований Results of current research Результаты исследований Large-scale flow model for solar and stellar convection zones Модель крупномасштабных течений в конвективных зонах Солнца и звезд Кичатинов Леонид Леонидович Kitchatinov Leonid Leonidovich kit@iszf.irk.ru

доктор физико-математических наук;

doctor of physical and mathematical sciences;

 Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar-Terrestrial Physics SB RAS Irkutsk Russian Federation 10 12 2025 10 12 2025 11 4 5 16 29 05 2025 15 07 2025 https://naukaru.ru/en/nauka/article/109290/view

В рамках гидродинамики средних полей создана модель крупномасштабных течений в конвективных зонах Солнца и подобных Солнцу звезд, обобщающая предшествующие модели дифференциального вращения с учетом зависимости течения от времени и его отклонения от осевой симметрии. Модель реализована в виде программы численных расчетов, в которой применяется спектральный метод разложения по сферическим функциям в комбинации с конечно-разностным дифференцированием второго порядка точности по времени и радиусу. Первые расчеты показали близкое соответствие осесимметричной части течения данным гелиосейсмологии о дифференциальном вращении и меридиональной циркуляции. Картина затухающих во времени неосесимметричных течений, рассчитанных в модели, находится в качественном согласии с наблюдениями волн Россби на Солнце. Сформулирована задача дальнейшего развития теории крупномасштабных течений.

The paper presents a mean-field model for large-scale flows in convection zones of the Sun and solar-type stars. The model extends former differential rotation models by allowance for variations of the flow with time and its deviation from axial symmetry. The model is realized as a numerical code, which combines the spectral method of decomposition in spherical functions with second-order accurate finite-difference method in time and radius. First computations show close agreement of the axially symmetric part of the computed flow with helioseismological detections of differential rotation and meridional circulation. Patterns of the time-decaying non-axisymmetric flow computed with the model qualitatively agree with the Rossby waves observed on the Sun. The paper also formulates a problem for further development of the large-scale flow theory.

 Солнце звезды вращение конвекция турбулентность численное моделирование Sun stars rotation convection turbulence numerical methods Работа выполнена при финансовой поддержке Министерства науки и высшего образования РФ This work was financially supported by the Ministry of Science and High Education of the Russian Federation

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