Effect of instantaneous change of surface temperature and density on an unsteady liquid-vapour front in a porous medium

This article presents a comprehensive analysis of time dependent condensation model embedded in a porous medium with variations in liquid-vapour densities. Both similarity and asymptotic solutions for the unsteady liquid-vapour phase change front are obtained with the manifestation of various pertinent parameters. The obtained results are compared which congregate well as depicted clearly in graphs. Results indicate that with different diffusivity and contrast ratios, the similarity front parameter is found to be gradually declining with variation in a density ratio. We have shown for the condensation process, the ratio of sensible to latent heat is independent of time and is equal to the half of the Stefan number of the liquid phase.