Mark Megahan
A team of scientists from City University of Hong Kong came up with a massive breakthrough in applied physics. They designed a “structured thermal armor” strong enough to stand up to the Leidenfrost effect. It’s a problem that their kind have been working on solving for 266 years now. The efficient liquid cooling magic works even at a seriously impressive 1,000°C, (1,832°F) making the technology perfect for use in things like rocket engines and nuclear reactors.
Thermal miracle achieved
You don’t have to be a rocket surgeon to understand how the miraculous thermal armor works. Many people are intimately familiar with the Leidenfrost effect even though they never even heard of it. Anyone who ever saw drops of water dancing across a hot skillet has seen the effect in action. In 1756, the bigwig alchemists noticed that water drops “levitate” on any surface which is a lot hotter than the boiling point of the liquid. For example, the intense heat of the flame under a skillet “produces an insulating vapor layer” which makes water drops dance until they evaporate.
No big deal to the kitchen magician, because it tells you when your pan is hot, but it “dramatically reduces heat transfer performances at high temperatures, which makes liquid cooling on the hot surface ineffective.” That, it seems, drives industrial engineers crazy. Which is why they babble about the second law of thermogoddamics in their sleep.
Structured thermal armor solves the whole mess and they’re all set to apply it “in aero and space engines, as well as improve the safety and reliability of next-generation nuclear reactors.” The dragon’s breath has been tamed by Professor Wang Zuankai and his team at the Department of Mechanical Engineering.
That includes Professor David Quéré from the PSL Research University, France, and Professor Yu Jihong, Director of the International Center of Future Science. They got to publish in “the highly prestigious scientific journal Nature.”
The gizmo they came up with is made of “a multitextured material with key elements that have contrasting thermal and geometrical properties.” That means, it gets it’s ability to move heat in such tremendously efficient ways through it’s unique and heavily patented shape.
“The rational design for the STA superimposes robust, conductive, protruding pillars that serve as thermal bridges for promoting heat transfer.”
Efficient and controllable cooling
Bottom line, their thermal device “successfully inhibits the occurrence of the Leidenfrost effect up to 1,150 °C and achieves efficient and controllable cooling across the temperature range from 100°C to over 1,150°C.”
No applause, please, just throw money.
There’s a good chance they end up with a million dollars of dynamite money for their efforts, in the form of a Nobel Prize in physics. Alfred Nobel bequeathed his fortune from the invention of dynamite to fund the prize which bears his name.
The way thermal armor works, “an embedded thermally insulating membrane” is designed “to suck and evaporate the liquid.” Meanwhile, “underground U-shaped channels” are used to “evacuate the vapor.”
All their friends in physics circles are congratulating them. “This multidisciplinary research project is truly a breakthrough in science and engineering, since it mixes surface science, hydro- and aero-dynamics, thermal cooling, material science, physics, energy and engineering.”
They call the accomplishment “one of the holy grails in thermal engineering since 1756.” Until now, less efficient air cooling was forced to be used for applications which can be cooled much more efficiently with liquids now.
