Tuning substrate geometry for enhancing water condensation

Water condensation is an important phase change phenomenon whose applications range from power generation to water desalination. In the present study, we compared condensation occurring on two different substrates (namely square and strip) and demonstrated the effect of substrate geometry on water condensation. It is found that condensation on different regions of the same substrate is dramatically different due to different local vapor flux. In general, the condensation rate is linearly proportional to vapor flux while average vapor flux can be improved by creating geometrical discontinuity (strip substrate) within rigid substrates. Experimental result of water collection confirms that the condensation rate is increased by around 40% on the strip substrate compared to the square substrate. This study demonstrates that water condensation can be enhanced by rationally tuning the geometry of the condensation substrate. Performance of water condensation of a specific substrate can be predicated by simulating the vapor flux over the substrate.