Euler-Euler CFD modeling of fluidized bed: Influence of specularity coefficient on hydrodynamic behavior

Abstract Euler-Euler two-fluid model is used to simulate the hydrodynamics of gas–solid flow in a bubbling fluidized bed with Geldert B particles where the solid property is calculated by applying the kinetic theory of granular flow (KTGF). Johnson and Jackson wall boundary condition is used for the particle phase, and different amount of slip between particle and wall is given by varying the specularity coefficient (ϕ) from 0 to 1. The simulated particle velocity, granular temperature and particle volume fraction are compared to investigate the effect of different wall boundary conditions on the hydrodynamic behavior. Some of the results are also compared with the available experimental data from the literature. It was found that the model predictions are sensitive to the specularity coefficient. The hydrodynamic behavior deviated significantly for ϕ = 0 and ϕ = 0.01 with maximum deviation found at ϕ = 0 i.e. free-slip condition. However, the overall bed height predicted by all the conditions is similar.

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