Fig. 1: Condensation frosting on the surface.
From: Gradient droplet distribution promotes spontaneous formation of frost-free zone
a Schematic showing the parameters of the macro-ridged surface. b Scanning electronic micrograph (SEM) image of the surface. The inset shows a contact angle of ~100∘ with a 3 μL drop. c Schematic showing the setup for condensation frosting experiments. d Condensation frosting on a flat surface. The insets show the high magnification optical images of the condensates at 30 s and frost at 3600 s, respectively. Scale bar, 300 μm. e Condensation frosting on the macro-ridged surface H3D1. The inset shows the high magnification optical image of droplets on the top of ridge at 100 s. White dotted line indicates the propagation of freezing wave and yellow dotted line indicates evaporation wave in the multi-phase transition stage. Scale bar, 300 μm. f Gradient distribution of condensate droplets on the macro-ridged surface. g Schematic showing the frost-free zone formation at different stages on a macro-ridged surface.
