There was an explanation why a water particle could roll on the water without getting together

Research results of this strange phenomenon can be applied in many industries.

Have you ever seen scenes of tiny droplets rolling gently on the water? When it rains or when you pour some fresh milk into a cup? Studyers have just found an explanation for this strange physical phenomenon: it only happens under certain conditions.

Picture 1 of There was an explanation why a water particle could roll on the water without getting together

According to researchers at the Massachusetts Institute of Technology, to make a water particle float on the surface of the solution for a short time before dissolving into the solution below, the temperature between them must be different. In this latest study, they also found a way to control this phenomenon.

In most cases, if two types of solutions - of water drops and of solutions below - the same kind, they will immediately mix. But when a drop of water still floats and rolls on the surface of the solution, it turns into a " noncoalescence " phenomenon . And yet, it has great use in science too.

Picture 2 of There was an explanation why a water particle could roll on the water without getting together

Finding out why this "unincorporated" phenomenon occurs, we will develop more efficient dairy solutions, such as medicine, makeup or paint. This strange phenomenon can also be studied and applied to technologies such as microchannel conduction chips (microfluidic: which allows control of operation in a very small scale through one or more small channels of small size. more than 1mm): water particles can carry reactants to necessary locations on a chip surface.

For that reason, the "unity" phenomenon has been studied for a while. They were also able to reconstruct this phenomenon in many different ways - the water with the charge opposite to the solution will also occur.

They also know what factors affect "non-integration". For example, the viscosity of the solution, the surface tension, the height of water droplets when falling, electrical properties and particle size all play a role in the formation of water particles on the surface of the solution and the time its existence.

Picture 3 of There was an explanation why a water particle could roll on the water without getting together

After all these previous studies, the SAO question is still there and exactly how it is controlled is still unknown.

However, a study in 1996 suggested that the effect of temperature on solution inconsistency. Based on that premise, Michela Geri, MIT graduate student leading a research team conducted a mathematical test, determining the differences of temperature in this.

Picture 4 of There was an explanation why a water particle could roll on the water without getting together

"Based on our new hypothesis, engineers were able to determine the essential temperature difference needed to separate the water and the surface of the solution, and determine the maximum weight of the water particles so it can float , " Geri said.

" If you understand the basics, you can start designing things the way you want."

And to do this test, Geri created a box with a metal bottom, filled it with silicone oil, put it all on a heat-generating device - that could be heated, cooled, or kept heat. Geri used a syringe, pouring it onto the surface of a solution of water, which was also silicone oil.

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Example of a thermal platform (hot-cold plate) used in the above test.

The test was carried out with enough different temperatures, many viscosity levels of oil and different densities. The researchers used a high-speed camera to go back to the test, with a shot of 2,000 frames per second, to carefully observe the interaction of water droplets with the surface of the solution.

The results showed that the higher the temperature difference, the greater the inconsistency rate. With a 30 degree C difference, Ms. Geri was able to keep the water in a "non-consolidated" state for about 10 seconds. This is because the temperature difference will create convection - the flow of the air-covering layer to the water particle and to the surface of the solution. The higher the temperature, the more this flow of convection flows, it will prevent water particles from dissolving into the solution below.

The results of this experiment will be studied carefully, to know how to rain water, disperse chemicals, biological substances.

Research by a team of scientists has been published in the Journal of Fluid Mechanics.