A computational fluid dynamics investigation of various nanofluids in a boiling flow field

Abstract

Nowadays boiling phenomenon has been an important issue in various fields such as nuclear and petroleum industries due to enhancement of the total heat transfer coefficient. One method to increase the level of heat transfer coefficient is to add certain nanoparticles such as Al2O3 and CuO to the base fluid. The present paper concerns the effect of nanoparticles on forced convective boiling within the general-purpose computational fluid dynamics (CFD). The Reynolds Averaged Navier-Stokes equations accompanied by mechanistic model developed by Rensselaer Polytechnic Institute (RPI) have been used to simulate the boiling flow field with an Eulerian- Eulerian approach for each phase. In addition to validating the subcooled boiling flow field, it was shown that both nanoparticles would lead to an increase in the heat transfer coefficients and in the upper limit of concentrations, copper oxide in comparison with alumina nanoparticles would lead to higher amounts of heat transfer coefficients along the channel. In another effort in this study, it was shown that by increasing the level of wall heat flux to approximately 30 percent in the presence of 1 vol% copper oxide, the wall temperature as a design parameter has not been changed significantly near the channel exit due to the predominant contribution of the boiling part.