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arXiv · 2502.00974

Revisiting turbulent properties of solar convection with 3D radiative hydrodynamic modeling

Irina N. Kitiashvili·Alan A. Wray
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Abstract

We discuss the turbulent structure and dynamics of the upper solar convection zone using a 3D radiative hydrodynamic simulation model at 45 degrees latitude. The model reveals the self-formation of meridional flows, the leptocline, and the radial differential rotation. Unlike previous studies, the model shows a complex variation of the characteristic scales of turbulent flows with depth. In particular, an increase in the characteristic convective scale is trackable within an individual snapshot up to a depth of 7 Mm, near the bottom of the hydrogen ionization zone, where turbulent flows become weaker and more homogeneous. However, the turbulent spectra show an increase in scale with depth and a qualitative change in convective patterns below 7 Mm (near the bottom of the leptocline), suggesting changes in the diffusivity properties and energy exchange among different scales.

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Irina N. Kitiashvili, Alan A. Wray. 2025-02-03. Revisiting turbulent properties of solar convection with 3D radiative hydrodynamic modeling. https://arxiv.org/abs/2502.00974

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