Numerical study of oscillatory convection during melting of ice in a rectangular enclosure

A numerical investigation concerning natural-convection-dominated melting process of ice inside a rectangular enclosure has been performed to assess the inception of temporally oscillatory convective flow and heat transfer at high Rayleigh numbers previously unexplored. Numerical simulations using a finite-difference method on a fixed grid have been undertaken for the two-dimensional ice-melting process in the enclosure with an aspect ratio of 0.5 under the following ranges of the relevant physical parameters: Ra-H, = 10(6) similar to 7 x 10(7), Ste = 0.101, and Se = 0.1 and 0.5. Numerical results reveal that for Ste = 0.101 and Sc = 0.5 with Ra greater than or equal to 1.2 x 10(7), temporally oscillatory convective flow and temperature fields arise in the water region during the melting process inside the enclosure. Supplemental to the numerical simulations, temperature visualization experiments by means of a thermochromic liquid crystal as tracer have been conducted in a test cell mimicking the physical configuration under consideration.