Splash Happens Before Drops Touch Surface

Turns out, splashing could occur even before the drop comes in actual contact with the surface, reveals a new study.

Splashing is one the key factors in transporting pollutants and spreading of diseases. However, splashing could occur even before the drop comes in actual contact with the surface, reveals a new study.

While the sight of a droplet striking and splashing off of a solid surface is a common experience, the actual physical ingredients and mechanisms involved in splashing aren't all that well understood.

Waterborne Infections Account for Healthcare Costs of Over 500 Million a Year
The Centers for Disease Control has said that hospitalizations due to three types of waterborne diseases cost the US health care system around 539 million dollars a year.

A team of Brown University and Harvard University researchers has discovered that there is indeed more involved in splashing than previously believed, the Newswise reported.

"In recent studies, it was highlighted that the surrounding air plays an important role in the splashing process. Decreasing the ambient pressure inhibits splashing," said Julie Albagnac, a postdoctoral research associate in engineering at Brown.

"The observations led to a hypothesis of the existence of a thin layer of air trapped between the drop and the surface."

Experts Are Optimistic Of Making Waterborne Infectious Diseases A Thing Of Past
Health experts have stated that waterborne infectious diseases could soon be consigned to history.

To better understand droplet splashing, the researchers initially wanted to observe and measure this layer of trapped air.

They hypothesized that splashing takes place while the drop is still spreading on an air film.

Water Borne Diseases causing More Havoc in Mumbai
The receding flood waters are causing a major health calamity in Mumbai with another 14 deaths were reported from Mumbai taking the toll in this worst affected

Unfortunately, they found that experimental equipment available today isn't sophisticated enough to catch a length as small as the air layer thickness (hundreds of nanometers) during the short time of existence of this air layer (hundreds of nanoseconds).

So they instead studied the time evolution and behaviour of droplets splashing with various impact velocities under a variety of ambient pressures to examine different scenarios involving splashing.

About Water Borne Diseases
Waterborne diseases are communicable diseases caused by diseases causing microorganisms in contaminated water. It is more prevalent during floods and in tsunami affected areas.

"This study shows a new signature of a precursor to the splashing through the wriggling of the contact line at the interface between the droplet and the surface," said Albagnac.

The splashing/spreading of a droplet doesn't seem to be an on/off situation, according to the team.

A transition regime exists between the spreading and splashing, which they observed by changing either the impact velocity or the ambient pressure while the other is fixed.

Source-ANI