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Abstract Drops are exceptionally mobile on lubricant-infused surfaces, yet they exhibit fundamentally different dynamics than on traditional superhydrophobic surfaces due to the formation of a wetting ridge around the drop. Despite the importance of the wetting ridge in controlling drop motion, it is unclear how it dissipates energy and changes shape during motion. Here, we use lattice Boltzmann simulations and confocal microscopy to image how the wetting ridge evolves with speed, and construct heatmaps to visualize where energy is dissipated on flat and rough lubricated surfaces. As speed increases, the wetting ridge height decreases according to a power law, and an asymmetry develops between the front and rear sides. Most of the dissipation in the lubricant ( >75%) occurs directly in front and behind the drop. The geometry of the underlying solid surface hardly affects the dissipation mechanism, implying that future designs should focus on optimizing the surface geometry to maximize lubricant retention.

Wong et al report that the Antarctic scallop Adamussium colbecki appears to remain ice-free in shallow Antarctic marine environments where underwater ice growth is prevalent. They find that micro-ridge structures in the shell promote directed icing that may prevent the dangerous accumulation and firm attachment of buoyant ice.

Wong et al. demonstrate the efficacy of super-amphiphobic surfaces for in situ defoaming and inhibition of foam growth while handling aqueous solutions. Without the use of chemical additives, their passive approach suggests a facile alternative route to froth management in industrial processes.