Influence of new superhydrophobic micro-structures on delaying ice formation

Drop motion on different types of new proposed micro-structure surfaces has been numerically investigated to find the optimum structure in view point of ice formation delaying. The droplet automatically moves on the inclined surfaces due to gravity forces. To validate the numerical algorithm, three different bench mark problems have been considered. The results indicate that the present algorithm is trustable for the presented numerical simulations. Then the validated numerical approach has been used to simulate droplet motion on nine proposed superhydrophobic surfaces in the same conditions. Comparison the drop motion on different micro-structure surfaces at different time indicate that creation of most micro-structure coating on smooth surfaces causes larger equilibrium contact angles and delays ice formation. For better understanding the results, the air flow structure trapped in the grooves have been plotted and investigated for some cases and the extracted results have been discussed in view of ice formation. It is found that the micro-structure in which the grooves’ upper surface is greater than the lower one, may cause worse hydrophobicity conditions than the smooth one. Also, adding hierarchical structures to the micro grooves creates better ice repellency conditions. Structures which prevent formation of secondary vortices, like circular grooves, are more preferable to other micro-structures in view point of ice formation