Nanotechnology Application for Boiling Enhancement

Boiling is an effective heat transfer mode which has an important place in engineering disciplines. In many industrial fields related to energy conversion such as electronic cooling systems, solar collectors,heat pipes, and nuclear reactors, improving the performance of boiling heat transfer based on surface treatment and modification is a key issue.Nano/microscale surface manipulation technique to control the surface roughness, porosity and the wettability is a new challenging field for performance enhancement in boiling heat transfer. Due to the importance of this issue, works on the new nanotechnology related methods for boiling enhancement are investigated. General findings show that the wetting characteristics of a substrate can be varied by proper selection of the process and materials for creating nanostructured surfaces.Hydrophilic and hydrophobic surfaces with nanoscale roughness are adequate to produce heterogeneous boiling. Hydrophobic surfaces provide better boiling heat transfer coefficient and hydrophilic surfaces increase the critical heat flux. Furthermore, recent experiments illustrate that heterogeneous wetting via a mixed hydrophobic/hydrophilic material is contemplated as a means of realizing the best boiling aspects of both types of surface. Based on the findings, it is suggested that future work should focus on a better understanding and control of boiling mechanism enhancement.

کلیدواژه ها:

nanostructure ، nanofluid ، pool boiling ، enhancement ، heterogeneous