CFD simulation of cooling superheated surfaces by nanofluids.
Eugene Strativnov1, Nie Guochao2
estrativnov@gmail.com

1The Gas Institute of NAS of Ukraine, 39, Degtyarivska str., 03113, Kyiv, Ukraine
2School of Physics and Telecommunication Engineering, Yulin Normal University, Yulin 537000, China

Recently, using of nanofluids (NFs) as a coolant in various fields of science and technology is rapidly developing. Because of the physical properties of the NFs differ significantly from the “classical” coolants (various liquids without adding of solid particles). It is why scientists of a world strive to find out as soon as possible the operation mechanism of NFs under various conditions of heat transfer. There are many scientific approaches and methods for studying this problem. One of these methods is computer simulation of physical processes by computational fluid dynamics (CFD). The undoubted advantage of this practice is the ability of accurately study physical phenomena at the macro and micro levels, in contrast to the technique of full-scale experiment, due to the impossibility of making the appropriate measurements in real conditions. However, computer simulation without verification of its main results by real experiment can lead to incorrect conclusions. Therefore, the main stages of a water boiling simulated in various conditions and compared with experiment and the available literature data. 
Fig. 1. CFD simulation of cooling an overheated body process.
This work includes such main points: Simulation of water heating process in conditions of natural convection (boundary conditions of the first and second kind) taking into account boiling, evaporation and condensation. Simulation of sedimentation of solids (nanoparticles: Al2O3 particles 70…300 nm) in still water. Simulation of cooling preheated solid body by water and NFs under natural convection conditions (third and fourth boundary conditions) taking into account boiling, evaporation, and condensation in the liquid phase and the temperature gradient in the solid. This work should be regarded as a don’t completed study; it is simply a timid attempt to come a little closer to understanding the mechanism of working of NFs on the physical level.