Investigation of gas-solid two-phase flow across circular cylinders with discrete vortex method

In present paper, a Lagrangian-Lagrangian model is proposed to study gas-solid two-phase flow across single cylinder and two tandem cylinders at high Reynolds number. In this model, the single-phase flow is simulated by discrete vortex method and the particle trajectories are tracked by particle motion equation. A sub-cycle is introduced to adjust time-step in the particle collision model, through which the simulation of two phases is coupled. Validated by the comparison of the particle trajectory in Rankine vortex with literature, this model is used to study single-phase flow across single cylinder and cylinders with different arrangements firstly to get transient flow field and drag coefficients. Then, gas-solid two-phase flow across cylinders with different arrangement is studied and particle distribution is obtained under different Stokes number for horizontal and vertical particle transport cases. The settlement, entrainment and aggregation of solid particles moving with the large-scale coherent vortex structure in the wake of single cylinder and between two cylinders are numerically investigated, and the effects of St number on the distribution of solid particles are obtained.