Solidification of an Aqueous Salt Solution in a Circular Cylinder

The situation of one-dimensional, transient inward solidification of a binary solution in a circular cylinder is studied numerically. The solution is assumed to be of a hypoeutectic initial concentration and to be initially at a superheated temperature above its initial melting point temperature. The boundary temperature of the cylinder is below that of its heterogeneous nucleation temperature and no supercooling occurs. The boundary temperatures and final solution concentrations are assumed to be above and below, respectively, the eutectic point of the solution. The finite difference numerical model predicts the time for the radial formation of the mush type of ice to reach the center of the cylinder and the time for the entire cylinder to reach the cylinder boundary temperature, based upon the assumptions of negligible diffusion and convection of solute during solidification. The results reveal that closure times are significantly increased for the solutions compared to pure water due to decreased conductivity of the mush compared to ice.