Figure 5
From: Enhanced condensation heat transfer using porous silica inverse opal coatings on copper tubes
Time-lapse images of water condensation on copper tubes subject to varying surface treatments, showing different modes of condensation. (a) FWC on a smooth plasma treated copper tube, (b) DWC on smooth hydrophobized copper tube, (c) IOC on silica inverse opal-coated copper tube, and (d) SLIPS condensation on oil-impregnated porous structure. In all cases except IOC, condensate was drained vertically downwards when gravity overcame pinning forces. During IOC, however, the condensate was transported preferentially in the axial direction through the cracks. Depending on the geometry, size, and orientation of the crack, the condensate moved axially to the right or to the left, but never vertically.
