That’s the way the droplets adhere
Understanding exactly how droplets and bubbles stick to surfaces — everything from dew on blades of grass to the water droplets that form on condensing coils after steam drives a turbine in a power plant — is a “100-year-old problem” that has eluded experimental answers, says MIT’s Kripa Varanasi. Furthermore, it’s a question with implications for everything from how to improve power-plant efficiency to how to reduce fogging on windshields.Now this longstanding problem has finally been licked, Varanasi says, in research he conducted with graduate student Adam Paxson that is described this week in the journal Nature Communications. They achieved the feat using a modified version of a scanning electron microscope in which the dynamic behavior of droplets on surfaces at any angle could be observed in action at high resolution.Previous attempts to study droplet adhesion have been static — using drops of a polymer that are allowed to...