Abstract
An analysis was performed for the melting heat transfer in a spherical capsule using n-octadecane as the phase change material. Special attention was focused on obtaining solutions at high Rayleigh numbers (i.e., for large diameter). To this end, the following three tools were incorporated : (i) To save computation time, a high accuracy, multi-point explicit finite difference scheme was adopted (ii) To improve the accuracy of computation near the wall, the scaled-grid spacing method was adopted ;(iii) To suppress the strong numerical instability, the least square method of six order was devised. Furthermore, transient aspects for natural convection flow in liquid phase, temperature profiles, melting interfaces, and stored heat fractions were clarified in detail.
