Extensive analysis of hydrodynamics in liquid–solid fluidized beds with particle-resolved simulations

Particle-Resolved Simulations (PRS) of fluid-solid particles are performed to investigate the hydrodynamics of liquid–solid fluidized bed. The various physical phenomenon contributing to turbulence generation in fluidized beds are first analyzed. A liquid–solid fluidized bed reproducing the experimental configuration of Corona et al. (2011) is then investigated. Four fluidization velocities are considered, corresponding to solid volume fractions ranging from 0.13 to 0.35. Grid sensitivity is examined with 12 and 24 grid cells per particle diameter, and a refined resolution of 36 cells per diameter is investigated at the lowest fluidization velocity. Particle and fluid statistics are computed using both Lagrangian and Eulerian approaches. The results show that the bed expansion height is accurately predicted even with the coarsest grid resolution. However, higher spatial resolutions are required to correctly capture the fluctuating kinetic energy profiles and the autocorrelation of the vertical fluid velocity. Finally, an extension of the correlation proposed by Alméras et al. (2019) is introduced to predict the fluid velocity variance as a function of the mean fluid velocity, solid volume fraction, and Stokes number based on the terminal settling velocity. The proposed correlation is validated for Stokes numbers up to 7.