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arXiv · 1703.01714

Hydrodynamic turbulence in quasi-Keplerian rotating flows

Liang Shi·Bjoern Hof·Markus Rampp·Marc Avila
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Abstract

We report a direct-numerical-simulation study of Taylor-Couette flow in the quasi-Keplerian regime at shear Reynolds numbers up to $\mathcal{O}(10^5)$. Quasi-Keplerian rotating flow has been investigated for decades as a simplified model system to study the origin of turbulence in accretion disks that is not fully understood. The flow in this study is axially periodic and thus the experimental end-wall effects on the stability of the flow are avoided. Using optimal linear perturbations as initial conditions, our simulations find no sustained turbulence: the strong initial perturbations distort the velocity profile and trigger turbulence that eventually decays.

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Liang Shi, Bjoern Hof, Markus Rampp, Marc Avila. 2017-03-06. Hydrodynamic turbulence in quasi-Keplerian rotating flows. https://doi.org/10.1063/1.4981525

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