Effect of patterned condensation surface on the performance of a newly designed basin-type solar desalination unit

Abstract

Evaporative solar desalination systems present a cost-effective solution for generating clean water from brine solutions or seawater. This study investigates the impact of condensation surface inclination, surface pattern, and wettability on the performance of a newly proposed basin-type solar desalination unit using computational fluid dynamics (CFD) based simulations. The proposed design of the system shows better performance in terms of water production compared to previously developed conventional units. It was observed that the wettability-based patterning with different arrangements on the condensation surface has a significant effect on the rate of water condensation. Five different cases of surface patterning on the condensation surface were considered. In one case, coatings of alternating hydrophobic and hydrophilic strips were considered (termed as Pattern-I, Pattern-II and Pattern-II for different cases based on the hydrophilic and hydrophobic coverages). In another case, small rectangular patches of hydrophilic (or hydrophobic) layers were coated on a hydrophobic (or hydrophilic) base substrate (termed as checkerboard Pattern-IV or V). The result shows 75.0% more efficiency for a checkerboard-based surface (Pattern-IV) and 150% more efficiency for a strip-based (Pattern-II) pattern than the pristine wettability surface of conventional design. Furthermore, the validation of the surface characteristics was performed based on available literature which implied satisfactory performance.