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arXiv · 2501.11761

Strong and weak dynamo regimes in Taylor-Couette flows

A. Mishra·G. Mamatsashvili·F. Stefani
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Abstract

We reveal a nonlinear magnetic dynamo in a Taylor-Couette flow at small magnetic Prandtl numbers $Pm\leq 1$, which has been previously believed to exist only at higher $Pm\gtrsim 10$ in this flow. The amplitude of initial perturbations, $Pm$ and domain aspect ratio play a key role in the onset and evolution of the dynamo. It exists in two main states -- a weak state dominated by large-scale modes and a strong, turbulent state with higher amplitude dominated by small-scale modes. These findings can be important for dynamo processes in various astrophysical objects with small $Pm$.

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A. Mishra, G. Mamatsashvili, F. Stefani. 2025-01-20. Strong and weak dynamo regimes in Taylor-Couette flows. https://arxiv.org/abs/2501.11761

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