Researchers demonstrate enhanced passive convective cooling using cellulose nanofiber films designed based on kirigami.
Due to the increasing demands of high computational power, computer manufacturers attempt to pack more and more transistors into their miniaturized microchips. With this, thermal management becomes complicated, and removing heat becomes increasingly challenging. Moreover, currently used passive cooling systems such as heat sinks, and spreaders are bulky and rigid. As a result, these techniques cannot be employed in emerging wearable electronic devices. Here, more flexible heat dissipation methods are required.
Researchers from SANKEN (The Institute of Scientific and Industrial Research) at Osaka University, Oita National College of Technology, and Tokyo Polytechnic University demonstrated enhanced passive convective cooling using cellulose nanofiber films designed based on kirigami, a traditional paper design form similar to origami.
The kirigami films have better cooling properties than uncut films (origami) by default, but applying air flow to them dramatically improves the cooling ability. The team performed a heat-dissipation test with irradiated light on a graphite-blackened area and found a drastic difference in the maximum temperature between the kirigami film and the uncut film under air flow. The thermal resistance was reduced to about one-fifth without the kirigami system.
“The kirigami heat-dissipation concept enables new thermal designs using various film materials as heat-dissipation components and is expected to inspire a wide range of new cooling devices and methods for use in next generation electronics” senior author Masaya Nogi says.
The researchers believe that their approach could help in the development of the next generation of wearable devices.
The work is described in the journal NPG Asia Materials.