Investigation of the gas-solid two-phase flow characteristics inside a fluidized bed reactor

By simulating the particle phase flow based on the particle kinetic theory and taking into account the two phase interaction by using the fluid and particle two phase flow theory, established was a CFD (computational fluid dynamics) model featuring the multiple phase flow inside a fluidized bed nuclear reactor, and numerically simulated and studied were the fluid kinetic behaviors in the above-mentioned reactor. The calculation results show that the distribution of particle concentrations on the cross section obtained by using Gidaspow drag force model shares a comparatively close tendency to that of the currently available test results. The particle concentration at the center of the central jet zone is relatively high. After dropping step by step to a partial minimum value, it will gradually increase with an increase of the radial distance. The particle concentration in the annulus zone remains basically unchanged. The influence of the action force between the fluid and particles as well as the particle elastic recovery coefficient etc. on the kinetic characteristics of the fluid in the reactor was analyzed. The research results show that the greater the particle collision recovery coefficient, the more uniform the particle concentration distribution on the cross section in the flow field.