Numerical study of the influence of coagulation on the dynamics of a two-fraction gas suspension

The work is devoted to mathematical modeling of the dynamics of solid or liquid dispersed inclusions suspended in gas-gas suspensions. The study numerically simulated the dynamics of a gas suspension in a channel with and without taking into account the effect of coagulation of dispersed inclusions. It was assumed that a dusty medium is moving in the channel, and droplet fractions are blown through the side surface of the channel, coagulating with dispersed inclusions of the dusty medium. The paper presents a mathematical model that implements a continuum technique for modeling the dynamics of multiphase media, which involves solving a complete system of dynamic equations for each of the phases of the mixture. The carrier medium was described as a viscous, compressible and thermally conductive gas. Interfacial momentum exchange and interfacial heat transfer were also taken into account. At the boundaries of the computational domain, modeled as solid surfaces, homogeneous Dirichlet boundary conditions were specified for the velocity components of the carrier medium and the dispersed phase. The dispersed phase of a gas suspension was described as multifractional, the fractions of which differ in the size of dispersed inclusions and the density of the particle material. The mathematical model assumed taking into account the interaction between particles, through the absorption of smaller particles by larger particles due to collisional coagulation. A comparison of the results with and without taking into account the effect of coagulation of the droplet and dust fractions of a gas suspension demonstrates that failure to take into account the coagulation effect has a significant impact on both the distribution of concentrations of gas suspension fractions and on the physical fields of the fractions and the carrier medium.