Compact nanostructure integrated pool boiler for microscale cooling applications

Abstract

An efficient cooling system without any external energy consumption that consists of a plate, on which an array of copper nanorods with an average diameter ~100 nm and length ~500 nm is integrated to a planar copper thin film coated silicon wafer surface, a heater, an aluminium base and a pool was developed. Heat is efficiently transferred from the nanostructure coated base plate to the liquid in the pool through boiling heat transfer mechanism. Phase change took place near the nanostructured plate, where the bubbles started to emerge because of the existing wall superheat. Bubble formation and bubble motion inside the pool resulted in effective heat transfer from the plate surface to the pool. Surface temperatures were measured and heat transfer coefficients were calculated for two working fluids; namely, water and ethanol. In this study, it was shown that using nanostructured surfaces can have the potential to be an effective method of device cooling for small and excessive heat generating microsystem applications, such as microelectromechanical systems, or microprocessors.