The effect of the high particle mass loading on the collection efficiency and particle-cut characteristics of the impactor and the particle motion in turbulent impinging round jet are numerically studied.
In the high particle mass loading study, the flow is assumed to be laminar, dilute and two-way coupled. The vorticity-stream function approach is used to solve the gas phase flow field. Particle momentum equation is described by the Lagrangian approach. PSI-cell(Particle-Source-In cell) model for the computational scheme is used to account the interacting force term between the gas and particles. Results say that the effect of the particle interactions with the gas on the collection efficiency is enlarged as the amount of the particle mass loading increases. And this phenomena gets outstanding when the value of Reynolds number or the overall particle sizes increases. the effect of the high particle mass loading on the collection efficiency is found to be considerable even in slow flows when particles are large.
In the study of the particle motions in turbulent impinging round jet flow, it is assumed that the gas-particle flow is one way coupled. The gas flow field is solved using a standard K-ε model and the wall function model for the boundary conditions. Lagrangian approach is used for the particle momentum equation, since the gas flow field has the high acceleration region near the impinging region. LSD model is applied to account the gas flow fluctuation effect on the particle motion. The results say that the effect of the turbulence characteristics on the particle motion is not negligible but it is less significant than that of the mean flow and geometry conditions.