Micro heat pipes to turn nano fluid into hydraulic fluid

researcher's name
about researcher KATSUTA, Masafumi Professor (retired)
Faculty of Science and Engineering School of Creative Science and Engineering


Heat pipes are air tight containers that are filled with a small amount of hydraulic fluid, vacuum sealed, and fitted with wicks (capillary structures). When one portion of a heat pipe is overheated, a series of continuous phase changes is set off as follows, causing the heat to move quickly through the pipe. 

1. The hydraulic fluid evaporates in the heating head.

2. The steam moves to the cold area of the pipe.

3. The steam condenses in the cold area.

4. Along with the continued shrinking of electronic devices, there is demand to further enhance the properties of heat pipes to create micro heat pipes – small high performance pipes in which condensed liquid returns to the overheated area – to act as suprathermal conductors for micro device cooling.


This project will improve heat conductivity by using a hydraulic fluid containing silver nano-particles in a micro heat pipe.


The technology will be applicable in various fields in addition to its uses for small electronic device cooling (things like notebook PCs and mobile transmission devices).


In addition to heat pipes this project is producing countless research achievements for heat transfer engineering, the fundamental base of thermal energy systems design for products such as heat pumps and absorption refrigeration.

purpose of providing seeds

Sponsord research, Collaboration research, Technical consultation

related paper

  • Heat conductivity of flat micro heat pipes using hydraulic fluid containing silver nano-particles, from the Collection of Papers for the National Heat Transfer Symposium (2007, 2008, 2009), The Furukawa Electric Co., Ltd., Waseda University
posted: 2014/05/21