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arXiv · 1712.04895

Experimental investigation of the wake behind a rotating sphere

Maciej Skarysz·Jacek Rokicki·Sophie Goujon-Durand·Jose Eduardo Wesfreid
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Abstract

The wake behind a sphere, rotating about an axis aligned with the streamwise direction, has been experimentally investigated in a low-velocity water tunnel using LIF visualizations and PIV measurements. The measurements focused on the evolution of the flow regimes that appear depending on two control parameters, namely the Reynolds number $Re$ and the dimensionless rotation or swirl rate $Ω$, which is the ratio of the maximum azimuthal velocity of the body to the free stream velocity. In the present investigation, we cover the range of $Re$ smaller than 400 and $Ω$ from 0 and 4. Different wakes regimes such as an axisymmetric flow, a low helical state and a high helical mode are represented in the ($Re$, $Ω$) parameter plane.

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Maciej Skarysz, Jacek Rokicki, Sophie Goujon-Durand, Jose Eduardo Wesfreid. 2017-12-13. Experimental investigation of the wake behind a rotating sphere. https://doi.org/10.1103/physrevfluids.3.013905

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