Abstract
The effects of the initial temperature of the solid PCM on a transient direct contact melting were invesigated, analytically. Four types of boundary conditions, that is, the constant temperature at the top, the constant heat flux at the top, the constant heat flux at the bottom, and the constant heat transfer coefficient and the constant temperature of the medium at the bottom of the heating plate, respectively, were examined. The effects of the initial temperature for each boundary condition were investigated through the transient process of the direct contact melting, where the heat transfer phenomena within the liquid film formed between the solid and the heating plate was unsteady, for the case of initial temperature lower than the melting point. It was found, as the results, that the time required until to approach the quasi-steady state and the melting speed at the time depended seriously on the initial temperature. It was understood, at the same time, that the heat flux flowing into the solid was not negligible, even in the quasi-steady state. Then, effects of the non-dimensional parameters, appearing in relation to the initial temperature variation of the solid, were examined, qualitatively.
