Abstract
Heat transfer enhancement is one of key issues of saving energies and compact designs for mechanical and chemical devices and plants. We discover a high convective heat transfer performance compared to the well-known heat transfer correlations caused by nano- and micro-scale structure formed on the heat transfer surface: the maximum increase of heat transfer coefficient was around 80%. Moreover, we have done some experiments using a co-current flow heat exchanger. We also obtained high performance compared to the usual correlation. In order to form nano- and micro-scale structure on surfaces, we have developed three treatment methods of Nano-particle Porous Layer method (NPL method), Fine Precipitates method (FP method) and Nano- and Micro-scale Porous Layered Structure method (NMPLS method). We guess by the molecular dynamics simulations that the mechanism of heat transfer enhancement by nano- and micro-scale structure on surface might be an artificial property change in the vicinity of the interface by complex structures of particles and porous from nanometer to sub micrometer scales.
