Productivity estimation of a single-slope solar still: Theoretical and numerical analysis

This study investigates the ability of a 2-D CFD (computational fluid dynamic) simulation in estimating the hourly yield of a single-slope solar still. Moreover, a new equation based on Chilton–Colburn analogy is proposed to estimate the productivity of a solar still. The results are in a good agreement with the results of well known models. However, the accuracy of the CFD analysis in the prediction of Nu number is better than its accuracy in productivity estimation. The results also show that there is an optimum length in which the productivity is maximized. On the other hand, in a fixed length of a solar still, the specific height has an inverse effect on productivity. Moreover, the trend of water productivity is always similar to the trend of convective heat transfer coefficient. ► In a solar still, the value of hev/hc is a function of glass and water temperatures. ► The accuracy of CFD-simulation in prediction of Nu number is more than its accuracy in productivity estimation. ► In a fixed length, the specific height has an inverse effect on productivity. ► In a fixed height, there is an optimum length in which the productivity is maximized. ► The trend of water productivity is always similar to the trend of convective heat transfer coefficient.