Numerical prediction effects of particle–particle collisions on gas–particle flows in swirl chamber

Abstract

In this paper, a unified-second-order-moment two-phase turbulent model incorporating into the kinetic theory of granular flows for considering particle–particle collision (USM-θ) is proposed to study the turbulent gas–particle flows in swirl chamber. Anisotropy of gas–solid two-phase stress and the interaction between two-phase stresses are fully considered by constructing a two-phase Reynolds stress model and a transport equation of two-phase stress correlation. Sommerfeld et al. (1991) experimental data is used to quantitatively validate USM-θ and USM model for analysis the effects of particle–particle collision. Numerical predicted results show that time-averaged velocity and fluctuation velocity of gas and particle using particle temperature model are better than those of without particle temperature model. Maximum particle concentration and temperature located at thin shear layer adjacent to wall surface due to particle inertia. Small-scale particle fluctuation due to particle–particle collision is smaller than large-scale gas–particle turbulence fluctuation. Particle–particle collision leads to the redistribution dissipation of Reynolds stress and particle turbulence kinetic energy.