Enhancing the Productivity of Tubular Solar Still by Using the Phase Change Material

In this article, a theoretical simulation of a modified tubular solar still (TSS) integrated with a rectangular basin painted black color was investigated. The simulation was conducted out using a 2-dimensional computational fluid dynamics by COMSOL metaphysics software. The two different types of phase change materials- PCMs have been used as a heat storage medium; paraffin wax and stearic acid. Influence of several parameters PCM mass, solar radiation, wind speed and temperature environment (ambient temperature) was studied. Therefore, a set of numerical simulations were displayed out to study the effect of heat transfer within the TSS. A series of this analysis in various real weather conditions (Najaf, latitude = 32 degrees 1 ' 38.55 '' N, longitude = 44 degrees 19 ' 59.22 '' E) on the TSS with seven PCM layers having a different thickness (tPCM = 5, 10, 20, 30, 40, 50 and 60 mm) were performed. The simulation results indicate that within the daytime, a more applicably performance of TSS was achieved with 40 mm PCM (2.664 kg of paraffin wax or 3.143 kg of stearic acid) compared to TSS without PCM. They are shown that the proposed solar system with PCM is significantly better due to thermal loss reduction. In general, the system including paraffin wax is most effective with or without stearic acid. The results of the analytical simulation were validated with experimental field results. It was found a good agreement between the numerical data obtained, and the experimental data have been obtained (rMBE = 0.022).