The role of particle - particle interactions in bubbling gas - fluidized beds of Geldart A particles : A discrete particle study
نویسندگان
چکیده
Discrete particle simulations are by now well established as an effective tool to study the mechanics of complex gas-solid flows in gas-fluidized beds. In this study, a state-of-the-art discrete particle model is used to explore the role of particle-particle interactions in bubbling gas-fluidized beds of Geldart A particles. We find that the particle-particle interactions, including inelastic particleparticle collision; inter-particle friction and slightly cohesive forces, only have a negligible effect on the hydrodynamics of bubbling gas-fluidized beds of Geldart A particles. This is due to the fact that only a very small fraction of the energy input is dissipated during the non-ideal particle-particle interaction. We finally show that the selected drag correlation model significantly affects the bed hydrodynamics.
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