Leonardo Da Vinci’s Odd Household Observation Finally Explained By Scientists

If people wonder about this odd household phenomenon just like Leonardo da Vinci did in the 1500s, scientists now have a definitive answer.

Centuries ago, Da Vinci noticed that when he turns on the tap, the water splays out upon hitting the sink before it goes on down the drain. This is called the hydraulic jump, a phenomenon of liquids that occurs in kitchen sinks as well as in nature such as rivers and oceans.

In the new study published in the Journal of Fluid Mechanics, researchers explored the nature and origins of the strange phenomenon.

It's Not Just Gravity Behind The Everyday Phenomenon

According to a University of Cambridge report via Eurekalert, since the 1820s, many scientists believed that this behavior is partly caused by the gravitational pull. It is a long-held assumption that was challenged and debunked by the latest study from the university.

When the study first author Rajesh Bhagat tried firing jets of water on flat surfaces upwards and sideways, he noted that the exact same hydraulic jumps occurred as it would when the water is fired downwards. This implies that gravity plays a much smaller role than presumed.

Bhagat, who is a Chemical Engineering PhD student at the St John's College, University of Cambridge, suggests that the phenomenon could be affected by surface tension and viscosity.

In the research, he manipulated these two factors to accurately predicted the size of the hydraulic jumps, regardless of the direction of the water.

Professor Paul Linden of the University of Cambridge hails the new study, saying it is a ground-breaking step in understanding the behavior of thin layers of fluid.

"His experiments and theory show that the surface tension of the liquid is the key to the process and has this has never before been recognised even though the problem was discussed by da Vinci and many others since," Linden adds.

The Practical Implications Of Hydraulic Jumps

While the hydraulic jump can be observed every day in the house, these new findings could have benefits reaching far beyond the kitchen sink. For one, it could be a game-changer in industries that work with massive amounts of water.

"Understanding this process has big implications and could reduce industrial water use dramatically," Bhagat says. "The new theory is already being used in practical work in the Chemical Engineering department. People can use this theory to find new ways to clean everything from cars to factory equipment."

He adds that the theory could also be used to find ways to reduce water consumption in households.