Researchers at Brown University in the United States, Thomas Dutta and Professor Jay Tang, have investigated the time it takes for the final drops of liquids like milk, olive oil, and maple syrup to drain from containers. Their study, published in Physics of Fluids, was inspired by common household frustrations: Dutta’s grandmother struggled with milk bottles, while Tang sought to optimize waiting time for residual water in his cast-iron wok after washing, aiming to prevent rust without removing the protective oil layer.

Using Navier-Stokes equations to model fluid motion, the scientists conducted experiments with a plate tilted at 45 degrees. They found that water drains in seconds, low-viscosity milk takes about 30 seconds, olive oil requires over 9 minutes, and cold maple syrup needs several hours for 90% drainage. For the wok issue, Dutta’s computer simulation revealed that about 15 minutes is needed for 90% of residual water to collect at the bottom, far longer than Tang’s usual 1-2 minute wait, highlighting a gap between intuition and fluid dynamics.

This work falls under “ludic science,” a playful and curious approach to natural sciences recognized by the Mario Markus Prize, awarded by the German Chemical Society since 2022 with a €10,000 reward. The prize celebrates discoveries like Alexander Fleming’s penicillin or Charles Goodyear’s vulcanization of rubber, which emerged from accidental experimentation, underscoring how everyday inquiries can yield significant scientific insights and foster innovation in unexpected ways.

Source: www.dw.com