A research team at the Korea Advanced Institute of Science and Technology has developed a method to prevent liquid from dripping when applied to surfaces facing downward, a problem famously associated with the struggles of Michelangelo while painting the ceiling of the Sistine Chapel in Rome more than 500 years ago.
My brush, above me all the time, dribbles paint
so my face makes a fine floor for droppings.
The institution said Thursday that the team led by mechanical engineering professor Kim Hyoung-soo reexamined how gravity interacts with liquids using interfacial fluid dynamics and proposed mixing a volatile liquid into fluids applied to ceiling surfaces.
Michelangelo is known to have complained about pigment dripping onto his face during the four years he spent painting “The Creation of the World” on the chapel ceiling. Such dripping has long been considered unavoidable because gravity continuously pulls liquid downward.
However, the research team found that adding a small amount of volatile substance changes how the liquid behaves as it evaporates, altering the concentration distribution along the surface of the fluid. This creates gradients in surface tension — the force that pulls a liquid’s surface inward and helps droplets maintain their shape.
The team explained that this phenomenon, known as the Marangoni effect, generates flows along the liquid surface as areas with higher surface tension pull liquid from areas with lower tension. The resulting flow helps hold the liquid against the ceiling and suppresses the instability caused by gravity pulling it downward.
According to Kim, the findings suggest that gravitational instability can be controlled without external energy input by relying on natural processes such as evaporation and changes in liquid composition.
The technology could be applied to industrial processes, including precision coating, printing and three-dimensional printing, as well as fluid control in environments such as space, helping stabilize liquids applied to downward-facing or tilted surfaces.
The study was published online Jan. 29 in the international academic journal Advanced Science.
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