Eulerian-Eulerian prediction of dilute turbulent gas-particle flow in a backward-facing step

A numerical study of turbulent gas-particle flow in a two-dimensional, vertically oriented backward-facing step is compared with literature data. The dispersed phase is modeled by an Eulerian approach based upon the kinetic theory of granular flow (KTGF) including models for describing the dispersed phase interactions with the continuous phase. The modeling of turbulent motion within the dispersed phase and the correlation between gas and particle velocity fluctuations are discussed. In addition, closure relations for the dispersed phase are extended to incorporate interstitial fluid effects. The continuous phase turbulence is modeled by a k-ϵk-ϵ model. This work demonstrates that treatment of turbulent characteristics is a key element in predicting the dispersed phase mean motion and turbulence modulation in the continuous phase. The derived models are implemented in a commercial code and simulation results are compared with benchmark experimental data for three particle classes with distinctive particle Stokes number, particle Reynolds number and mass-loading. In general, reasonable predictions are achieved.