By Josh Perry, Editor [email protected]
Researchers at the University of Edinburgh (U.K.) have discovered that ultra-fast vibrations can be used to heat tiny amounts of liquid and they believe that this could have a variety of applications, according to a report from the university.
Simulations showed that tiny amounts of water could be heated through ulra-fast vibrations. (Wikimedia Commons)
Edinburgh scientists demonstrated through computer simulations that tiny quantities of liquid could be brought to a boil if shaken at ultra-fast speeds. The article explained, “Liquid layers one thousand times thinner than a human hair can be boiled using extremely rapid vibrations – a million times faster than the flapping of a hummingbird’s wings.”
Researchers said that the motion of the vibrating surface under the fluid is converted to heat through the collision and movement of molecules. This process is only possible with tiny amounts of liquid that are only a few billionths of a meter above the vibrating surface.
“Energy from vibrations applied to larger volumes instead produces tiny waves and bubbles, and only a very small amount of heat,” the article said.
The research was recently published in Physical Review Letters. The abstract read:
“We report nonequilibrium molecular simulations of the vibration-induced heating of nanoscale-thick water layers on a metal substrate. In addition to experimentally confirmed acoustothermal evaporation, we observe hitherto unmapped nucleate and film boiling regimes, accompanied by the generation of unprecedented heat fluxes [∼O(109) W/m2].
“We develop a universal scaling parameter to classify the heat-transfer regimes and to predict the thickness of the residual nonevaporating liquid layer. The results find broad application to systems involving drying, coatings, and sprays.”
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