Combining level-set method and population balance model to simulate liquid–liquid two-phase flows in pulsed columns

Abstract

The level-set method and population balance model (PBM) were combined to develop a numerical framework for the simulation of liquid–liquid two-phase flows in a pulsed disc and doughnut column (PDDC). First, breakup behavior in droplet swarms in a local area of the PDDC was elucidated under a low holdup condition using a modified level-set method with multi-levels. The droplet breakup frequency function and the daughter droplet size distribution function were determined via statistical analysis on the breakup behavior in droplet swarms. The determined droplet breakup kernel functions were then plugged into the PBM to simulate liquid–liquid two-phase flows in the full-scale PDDC. The calculated droplet size distribution agreed well with the experimental results. The developed numerical framework provides a strategy to simulate two-phase flows avoiding the use of adjustable parameters which are dependent on experiments.