(356d) Discrete Particle Modelling and Analysis of Gas-Solid Flow in Pneumatic Conveying

Pneumatic conveying is an important operation used in industries to transport bulk materials from one place to another. To achieve optimal design and control of this operation, it is very important to understand the complex behaviors of the gas-solid flow along the conveying pipelines. In recent years, many efforts have been made in this direction by means of the numerical approach of combining discrete element method (DEM) for particles and computational fluid dynamics (CFD) for the gas phase. This talk will present an overview of CFD-DEM studies of pneumatic conveying in our laboratory, focused on two aspects: model development and model application. The model development is discussed in terms of model formulation, new features and model validation. Then, the usefulness of the CFD-DEM approach is demonstrated through some case studies where the main findings at the particle scale are highlighted. In particular, the flow regimes and their transition are unveiled in terms of the flow behaviors of gas and solid phases, the forces acting on particles, and the energy dissipation among gas, particles and pipe wall. Also, the CFD-DEM simulation of the large-scale pneumatic conveying is demonstrated, where the transport distance is around one hundred meters and the pipelines consist of horizontal, vertical and inclined pipes, as well as bends. Finally, areas for future development are briefly discussed.