Volume-of-Fluid Model for Simulating Vapor-Liquid Phase Change in a Solar Still

In this paper, a volume-of-fluid model is developed to simulate the vapor-liquid phase change in a modified solar still equipped with a porous layer in its basin. The results of the numerical simulation are compared with those of the moist-air model as well as available experimental data to benchmark the accuracy of this model. It was found that the volume-of-fluid model better matches the experimental data than the moist-air model. Finally, the role of a porous layer in improving the rates of evaporation and condensation in a solar still is examined by comparing the results to those of a conventional solar still. There is approximately 39% increase in the productivity when a sponge rubber porous layer with porosity of 0.4 is used in the basin of the solar still.