Flow Behaviors of Gas-Solid Injector by 3D Simulation with Kinetic Theory of Granular Flow

Abstract A computational study on the flow behavior of a gas-solid injector by Eulerian approach was carried out. The gas phase was modeled with k -ɛ turbulent model and the particle phase was modeled with kinetic theory of granular flow. The simulations by Eulerian two-fluid model (TFM) were compared with the corresponding results by discrete element method (DEM) and experiments. It was showed that TFM simulated results were in reasonable agreement with the experimental and DEM simulated results. Based on TFM simulations, gas-solid flow pattern, gas velocity, particle velocity and the static pressure under different driving jet velocity, backpressure and convergent section angle were obtained. The results showed that the time average axial gas velocity sharply decreased and then slightly increased to a constant value in the horizontal conveying pipe. The time average axial particle velocity increased initially and then decreased, but in the outlet region of the convergent section the particle velocity remarkably increased once more to the maximal value. As a whole, the static pressure distribution change trends were found to be independent on driving gas velocity, backpressure and convergent section angle. However, the static pressure increased with increase of convergent section angle and gas jet velocities. The difference of static pressure to backpressure increased with increasing backpressure.

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