EXPERIMENTAL AND NUMERICAL STUDY OF THE PARTICLE FLUCTUATING MOTION INDUCED BY COLLISIONS BETWEEN PARTICLES IN A VERTICAL GAS-SOLID FLOW

The effect of interparticle collisions on the gravitational motion of large particles in a vertical convergent channel is experimentally and numerically investigated. A probabilistic collision model is implemented in a three-dimensional Monte Carlo type Lagrangian simulation code. The numerical predictions are compared to the experimental results. It is shown that an interparticle collision model is necessary to reproduce the experimentally observed particle fluctuating motion characteristics. The simulation results using the present probabilistic collision model are found to yield satisfactory agreement with experimental observations, even though the collision frequency seems to be slightly overestimated. In particular, reduction of initial anisotropy of the particle fluctuating motion with increasing particulate mass flow rate is well reproduced by the simulation. A rather good agreement is also observed between experimental results and quantitative predictions of statistical properties of the flow such as particle axial and transverse velocity distributions and standard deviations.