Numerical Investigation of Influence of Nanoparticles Presence on Water Vapor Condensation Process inside a Vertical Channel

Abstract

This paper is aimed at investigating the nanofluid film condensation by mixed convection in the presence of water vapor, Cu nanoparticles, and air treated as a noncondensable gas (NCG) on the inner walls of a vertical channel. In this simulation, the flow is laminar, stationary, two dimensional, and axisymmetric. The coupled governing equations for the liquid film with the nanoparticles and the mixture air-humid-nanoparticles are solved together using the finite volume method. Since the application of humid air condensation is one of the most applicable methods of phase change processes that is observed in different industrial fields such as heating, ventilation, and air conditioning (HVAC) or cooling systems, for this purpose, the influence of injecting a uniform volume fraction of nanoparticles on improving heat and mass transfer is determined as a function of the variation in relative humidity, velocity, temperature, pressure, and volume fraction of Cu nanoparticles at the channel inlet. The numerical results indicate that under the best conditions in the range of variation studied ${\text{RH}}_{\text{in}}=100\%$ , ${\mathrm{Re}}_{\text{in}}=2000$ , $T_{\text{in}}={50}^{°}\text{C}$ , $P_{\text{in}}=0.5\hspace{0.17em}\hspace{0.17em}\text{atm}$ , and ${\phi }_{\mathit{\text{in}}}=0.1\%$ , the use of nanoparticles has a greater impact, and the maximum improvement in the condensation film thickness, the local Nusselt number, and the accumulated condensation rate has an effective ratio strictly greater than one compared with the case of pure humid air.