Ripples on the Surface of Icicles

Abstract

Ring-like ripples with wavelength about 1 cm appear on the surface of icicles during ice growth from a thin film of flowing supercooled water. This phenomenon is treated as the problem of morphological instability of solid-liquid interface during crystal growth from a thin shear flowing liquid with one side being a free surface. The length scale of the ripples is determined by a linear stability analysis of the interface, and a new mechanism of ripples formation is proposed.