What is the Thickness of the Ice Melting Front?

The melting front thickness of ice has been estimated from the measured kinetics of the melting of ice balls in air at room temperature (≈22°C) and in cooled water ( $$ \lesssim 1^\circ {\text{C}}$$ ) taking into account the temperature of the ice ball surface and the bulk temperature inside the balls. In both cases, the input heat is absorbed by ice in the form of the latent heat of fusion within the layer called the melting front. In order to describe the kinetics of the ice ball melting, we have developed a model with allowance for the heat transfer through the entire surface of the ice ball, which decreases during melting. The measured temperatures of the ice surface and the temperature inside the balls are approximately 0.4 and 0°C, respectively. The ice melting kinetics in cold water has been determined by means of the continuous measurement of the weight of the submerged ice ball (containing a lead ball frozen inside) as a function of time. In both cases (melting in air and water), the thickness of the ice melting front estimated from the fit the proposed model of experimental data is approximately 3 mm.