Abstract:

To investigate the behavior of gas-particle two-phase flow in the impinging streams gasifier，a 3D numerical model was used to simulate the flow field characteristics inside the gasifer.The model was based on the Euler-Lagrange concept.The gas flow was treated as continuous phase with an Euler frame of reference，while the Lagrange method was used to trace the particles.The behavior of inter-particle collision and its effects on particle dispersion were presented.The predicted results agreed well with cold-model and hot-model experimental data.In order to investigate the influence factors on the flow field that might have a significant effect on the coal gasification process，some parametric studies were performed by changing the gas-solid flow inlet velocity，size of particle distribution，and gasifier geometry.The results showed that the residence time of particles increased with the straight section height above the burner，and the deposition flux increased with the inlet velocity.The model and experiment results showed that the highest turbulence intensity and flame of collision converged near the center of the impinging zone.The inter-particle collision led to particle agglomeration，but the holistic distribution of particle concentration was reasonable.Finally，the parameter of particle size was also investigated，and the particles with a smaller Stokes number had weaker influence on the flow field.