A new “levitating” state of water is described KXan 36 Daily News

Scientists at Virginia Tech heated the surface to 550 degrees and forced the ice to rise above it on a pillow of steam. This discovery of the property of water was the addition of a phenomenon discovered in the 17th century. Work published в журнале Physical Review Fluids.

It is known that there are three phases of water: solid, liquid and gaseous. However, when the heat source is hot enough, the behavior of the water changes dramatically. A drop of water applied to an aluminum plate heated to 150 degrees or more will no longer boil. Instead, the vapor that is produced as the drop approaches the surface creates a cushion that prevents the liquid from making direct contact with the surface. This vapor causes the liquid to slide over the heated surface. This phenomenon is known as the Leidenfrost effect or boiling crisis described in 1751.

The team of scientists wondered: could ice behave in the same way? It turned out that it can – it is required to heat the surface to 550 degrees. At temperatures below this value, the ice continued to simply melt, and the melt water continued to boil. Boiling is prolonged by the temperature difference in the layer of water, which has two extremes – from above it comes into contact with ice and has a temperature of about zero, and from below – with a hot surface and warms up to hundreds of degrees. The ice consumed most of the surface heat, leaving only a small part of the energy to produce steam, and the desired effect was not obtained.

The temperature increased to 550 degrees optimizes all these processes. Making ice “levitate” is much more difficult than water, scientists say. Heat transfer drops off sharply as soon as “levitation” begins, because when the liquid is not in contact with the surface, it does not boil, nor does it produce steam, which in turn is needed to float above the surface.

The discovery of an additional property of water can have practical applications. According to scientists, this can be used to cool servers or car engines. Cooling them usually requires a substance or mechanism that can draw energy away from the hot surface, quickly redistributing heat to reduce wear on metal parts.

And the use of ice can be used in nuclear power plants for rapid cooling in the event of a power outage. In metallurgy, the production of alloys requires the removal of heat from metals that have been formed over a narrow period of time in order to give them strength. If ice were used, this would allow heat to be rapidly removed through the three aqueous phases, rapidly cooling the metal. Also, ice, theoretically, can be used in fire fighting.

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