Effect of particle-momentum on an isothermal flow-field inside a swirl combustor

Abstract

This paper investigates the impact of particles on isothermal flow inside a lab-scale swirl combustor for a fixed inlet swirl number of 0.67 using steady-state CFD simulations. The combustor geometry and baseline conditions, with no particles, are taken from Taamallah et al. [1], but with a simplification. In the present work, we provide rotation to the flow using velocity boundary condition, whereas in [1], a swirler is built into the geometry to achieve the same effect. Shear stress transport (SST) k-omega model, an eddy-viscosity based Reynolds averaged Navier-Stokes equation approach, is used for modelling turbulence. The comprehensive model is validated against the experimental axial-velocity data in [1]. Two simulations, one with 75 and another with 100 micron particles using Discrete particle model (DPM) were conducted to isolate the effect of particle motion on swirl-combustor flow without combustion. Their analysis shows significant downstream shift of central recirculation zone (CRZ). An effect that can significantly impact the stabilization of coal flame in pulverized particle reactors.