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arXiv · 1611.10131

Mean Flow Evolution of Saturated Forced Shear Flows in Polytropic Atmospheres

V. Witzke·L. J. Silvers
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Abstract

In stellar interiors shear flows play an important role in many physical processes. So far helioseismology provides only large-scale measurements, and so the small-scale dynamics remains insufficiently understood. To draw a connection between observations and three-dimensional DNS of shear driven turbulence, we investigate horizontally averaged profiles of the numerically obtained mean state. We focus here on just one of the possible methods that can maintain a shear flow, namely the average relaxation method. We show that although some systems saturate by restoring linear marginal stability this is not a general trend. Finally, we discuss the reason that the results are more complex than expected.

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V. Witzke, L. J. Silvers. 2016-11-30. Mean Flow Evolution of Saturated Forced Shear Flows in Polytropic Atmospheres. https://arxiv.org/abs/1611.10131

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