Homogeneous, High Packing Fraction Fluidization of Coarse Particles Using a Combination of Gas Flow and Vibration
When subject to both upward gas flow and vertical vibration, Geldart Group B and D particles are shown to fluidize at gas flow rates below that needed without vibration in a state with high particle packing fraction and no gas bubbles. We investigate the effects of particle size, superficial gas velocity and vibration strength on the minimum fluidization and minimum bubbling velocities in 3D and pseudo-2D beds. Further, we use particle tracking velocimetry in a pseudo-2D bed to measure the particle velocity distribution and understand how it compares to molecular and granular gases. We use theoretical analysis to uncover the physics underlying this non-bubbling fluidized state and test the capabilities of computational models of fluidization to reproduce the phenomenon. Finally, we investigate the capability of this homogeneously fluidized state to form structured flow patterns.