Damena Agonafer has developed a unique evaporative cooling system that uses a membrane with microscopic pillars (shown above) that are designed to remediate the heat from high-power electronic systems. (Image: Courtesy of Washington University in St. Louis)
Electronic systems, such as electric vehicles and large data centers, generate a lot of power, which creates tremendous heat. An engineer at Washington University in St. Louis has developed a unique evaporative cooling system using a membrane with microscopic pillars designed to remediate the heat, ultimately improving performance.
The method, developed by Damena Agonafer, assistant professor of mechanical engineering & materials science, is the first approach to retaining liquids using microfabricated micropillar structures. His theoretical, computational and experimental analyses are published in the March 15 print issue of the Journal of Colloid and Interface Science.
While a postdoctoral researcher at Stanford University, Agonafer developed a method to mitigate high heat-flux generation using water. However, water cannot be used safely in electrical applications, so Agonafer uses dielectric liquid, such as refrigerant, an electrical insulator in high voltage applications that has low surface tension. Unlike water, dielectric refrigerant, a low surface-tension liquid, can “wet” any standard surface.
“This work is the first demonstration of low-surface-tension liquid within porous membrane structures,” Agonafer said. “There are many ways to retain liquid inside or behind the porous membrane structure with high surface-tension liquid, such as water, with surface chemistry, but you can’t do any type of surface treatment with low surface-tension liquid, so this requires a certain type of microstructure to form an energy barrier and ‘pin’ these liquids.”
This advanced cooling technology will help unleash the full potential of next-generation electronics for a broad array of applications, including renewable energy storage, autonomous driving and public transportation, artificial intelligence, advanced communications and health care.
