Simulation of Phase Change Process of Nanofluid in Porous Media based on LBM

Abstract

In this study, a two-dimensional partially filled porous medium structure model, which is able to simulate porous wick, was constructed via the stochastic collocation method. Different porosities were controlled, and water and Al2O3–water nanofluid were used as working media. In addition, a lattice Boltzmann model that can describe the liquid phase transition process in porous media was used to verify the combination of the nanofluid phase transition model and porous media structure. Bubble formation and growth, bubble fusion, and solid wall collision rebound phenomenon were observed through the simulation of the nanofluid boiling phase change process in the partly filled porous medium structure cavity. Moreover, the flow patterns of gas–liquid two-phase flow in nanofluid and pure liquid were compared. Results show that the phase change heat transfer capability of fluid is enhanced, the nanoparticle size increases, and the heat transfer ability of the fluid decreases with nanoparticle addition.