Experimental Study on Velocity of Large Bubble and Velocity of Large Particle in Gas-Liquid-Solid Three-Phase Slug Flow with Large Particles in a Vertical Pipe

Characteristics of velocities of large bubble and of large solid particle of gas-liquid-solid three-phase slug flow with large particles are experimentally studied in a vertical pipe whose blockage ratio is larger than 0.8. Strong interactions between large bubble and large particle such as the destruction of a large bubble into small and/or medium bubbles by a large particle, the recovery of fragments of bubbles into their corresponding large bubble, the deceleration of large particle during its passing through a large bubble, and the acceleration of a large particle in the top part of liquid slug are observed. Three kinds of velocities are defined for large bubble velocity and for large particle velocity, respectively, in this turbulent and violent three-phase slug flow. The characteristics of these velocities are discussed against volumetric fluxes of gas phase, liquid phase, solid phase and total. Changes of each velocity from corresponding velocities observed in fundamental two-phase flows, namely gas-liquid two-phase flow and liquid-solid two-phase flow with large particles are explained.