MIT researchers claim a groundbreaking move after finding out how to control the process of boiling water using an electrical switch – a finding that will be integral to many electric power plants, desalination facilities, and heating and cooling systems.
Poised to assist in making electric power and similar processes more efficient, the discovery was described by the team from the Massachussets Institute of Technology (MIT) in a study published Oct. 21 in the journal Nature Communications.
According to the researchers, such degree of controlling the process of boiling – separate from temperature – had not been previously shown despite the importance of this function in industrial activities.
Electric fields have been used for controlling boiling but the process requires special fluids instead of mere water, as well as “a thousandfold higher voltage, making them economically impractical,” they wrote.
The discovery came about with the addition of surfactants to water, producing a soapy liquid. The molecules in the surfactant come with an electrical charge and can be repelled by or attracted to a metal – thus switching the metal surface from a state of hydrophilia to hydrophobia or vice-versa, said author and mechanical engineering professor Evelyn Wang.
The surface became more hydrophobic with the surfactant, increasing potential for bubble formation. On the other hand, reversing the charge led the surface to be hydrophilic, inhibiting bubbling from forming.
The researchers said that switching the charge, which does not require any special processing, can offer a ten-fold change in bubble formation rate. A switch in polarity can therefore be key in precisely controlling the rate of bubbling in the boiling water.
How then will managing bubble formation benefit industrial processes? According to the study, it controls heat transfer rate between metal and liquid, resulting in efficient boilers and a wide range of other applications.
Designs at present require a great safety margin to avoid hot-spots that could seriously harm the equipment.
It’s the ability for “real-time adjustments” in output without sacrificing efficiency, the researchers touted.
The benefits are believed to extend to liquid cooling for high-performing electronic items, which can also prevent overheating from occurring in hot-spots.
As power plant operators are deemed conservative about adjustments because of people who are dependent on their work, a demonstration plant will likely be necessary to show how the pioneering concept can work in a real-life, operational setting.
Rochester Institute of Technology professor Satish Kandlikar hailed the research for showing a novel way to control boiling, and said that such control techniques will “dramatically alter the heat transfer paradigm” implemented in electronic cooling and other fields.
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