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arXiv · 1510.06505

Rotation of a melting ice at the surface of a pool

S. Dorbolo·N. Adami·C. Dubois·H. Caps·N. Vandewalle·B. Darbois-Texier
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Abstract

Large circular ice blocks up to 80 m of diameter have been observed on frozen river around the world. This rare event has been reported in a publication in 1993. This fascinating self-fashioned object slowly rotates at about 1$^o$ per second. In this paper, we report a model experiment consisting in a 85 mm of diameter ice disc at the surface of a thermalised pool. The rotation speed has been found to increase with the bath temperature. Using particle image velocimetry technique, we evidence the presence of a vortex below the ice block. This vortex results from the descending flow of high density water at 4$^o$C. The vorticity of the vortex induces the rotation of the ice block. This mechanism is generic of any vertical flow that generates a vortex which induces the rotation of a floating object.

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S. Dorbolo, N. Adami, C. Dubois, H. Caps, N. Vandewalle, B. Darbois-Texier. 2015-10-22. Rotation of a melting ice at the surface of a pool. https://doi.org/10.1103/physreve.93.033112

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