Solidification of a liquid metal confined in a cylinder: Experimental and numerical study of the solid-liquid interface

Experimental data about the solidification process of low-temperature metals have not practically been described. This work explores the solid-liquid interface during the solidification process of liquid gallium. The experimental configuration consists of a cylindrical glass cavity with an internal diameter of 50 mm. It is filled with liquid gallium up to a height of 20 mm. An acid layer of 15 mm is deposited on top of the liquid metal. The lateral wall is covered with polyvinyl chloride tape, while the lower cap of the cavity is in contact with water from a refrigerated circulator. It can fix constant temperature values of 9.8, 12.3, 14.8, 17.3, and 19.8 degrees C. Since the fusion temperature is 29.8 degrees C, solidification starts from the bottom to the top of the cylinder. The solid-liquid interface is experimentally tracked using the ultrasound pulse-echo technique. Additionally, three-dimensional numerical study is carried out, and an idealized analytical model is developed. The experimental, numerical, and theoretical results are consistent. Correctly tracking the solid-liquid interface helps to understand the solidification process in recent energy storage technologies.