Radiation induced melting of a semitransparent phase change material

The objective of this paper is to present the results of a combined analytical and experimental study concerned with one-dimensional transient thermal response of a semitransparent phase change material as it is melted by subjecting it to radiative heating at the upper free surface. The slab of material is kept either isothermal or adiabatic at the bottom. Both the liquid and solid phases are considered to participate in the radiation transfer. In the analysis the model equations are solved using a variable grid numerical method with a fixed number of nodes in both phases. The numerical results are presented in terms of dimensionless parameters such as the Stefan number, Biot's number, thermal properties ratios, and the optical depth. The experiments were performed primarily to obtain data which was used to ascertain the validity of the model. It was found that the agreement between the model and the experiments was very good.