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arXiv · 1506.00875

Experimental study of a three dimensional cylinder-filament system

Nicolas Brosse·Carl Finmo·Fredrik Lundell·Shervin Bagheri
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Abstract

This experimental study reports on the behavior of a filament attached to the rear of a three- dimensional cylinder. The axis of the cylinder is placed normal to a uniform incoming flow and the filament is free to move in the cylinder wake. The mean position of the filament is studied as a function of the filament length L. It is found that for long (L/D > 6.5, where D is the cylinder diameter) and short (L/D < 2) filaments the mean position of the filament tends to align with the incoming flow, whereas for intermediate filament lengths (2 < L/D < 6.5) the filament lies down on the cylinder and tends to align with the cylinder axis. The underlying mechanism of the bifurcations are discussed and related to buckling and inverted-pendulum-like instabilities.

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Nicolas Brosse, Carl Finmo, Fredrik Lundell, Shervin Bagheri. 2015-06-02. Experimental study of a three dimensional cylinder-filament system. https://arxiv.org/abs/1506.00875

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