Abstract
The present authors have been conducting experimental study of high performance flat heat pipes to apply cooling of electronic devices, especially CPU in server. By using self-rewetting fluids, which show positive surface tension dependence on temperature, as working fluids, the thermal performances of flat heat pipes were improved. In addition, nanofluids with wire-shaped nano particles that nano particles directly synthesized in base fluids by the microwave polyol method are also used for heat transfer enhancement. Demonstration experiment of cooling system with these thin flat heat pipes for CPU was also carried out in real server, and cooling effect comparable to current air cooling system by fans was shown. In the meanwhile, thin plate-type heat pipes which have several kinds of wick structures have been developed and the encouraging thermal performance was obtained.
