Scientists from the University of Illinois at Urbana-Champaign have invented a new way to switch heat flows on and off. This could prove an enormous benefit for electronics systems, particularly those where controlling heat can have a drastic effect on the system’s reliability and overall performance. This research originally appeared in Applied Physics Letters.
Switches appear on a wide range of devices and systems. Typically these are mechanical or electrical switches. Mechanical switches can be used to open and close doors, while electrical switches can turn lights on and off in a room. Transistors are also a form of electrical switch, giving people the power to turn electrical devices on and off at will.
But switches for heat flows have long presented a problem for scientists. While they would be a major benefit when it comes to maintaining and controlling a variety of systems, there are numerous challenges and roadblocks that have prevented the idea of the heat switch becoming a reality.
“Heat flow occurs whenever you have a region of higher temperature near a region of lower temperature. In order to control the heat flow, we engineered a specific heat flow path between the hot region and cold region, and then created a way to break the heat flow path when desired.”
Scientists used a system modeled after modern electronics systems to demonstrate this new heat switch technology. A heat source representing the power electronics component was on one side of the switch. On the other they placed a liquid cooling system designed for heat removal. When they flipped the switch, scientists were able to successfully extract heat at more than 10 W/cm2. Once the switch was turned on, the heat flow dropped by an astounding 100X.
The next step in their research is to find a way to successfully integrate the new heat switch with power electronics. The switch will be integrated with electronics that rely on a circuit board for starters. Scientists believe they will have a fully functional prototype later this year. Should their efforts prove successful, this little switch could be the big change in electronics that scientists have been searching for.
