Numerical Simulation of Liquid–Liquid Dispersion Characteristics in Screen-Type Static Mixers by Two Simplified Zero-Dimensional Models

In this work, two different zero-dimensional (0D) modeling approaches as well as PLIF measurements were adopted to analyze liquid–liquid dispersion characteristics in screen-type static mixers. On the framework of the population balance model (PBM), the 0D lumped model based on the volume-averaged turbulent dissipation rate (εAvg) was solved by the fixed pivot technique to predict the evolution of the droplet size distribution (DSD). The 0D homogeneous model accounts for the spatial inhomogeneity behind screens by coupling a probability density function of ε, which was obtained by two-phase flow CFD simulations. Different breakage kernels were applied and compared. Predicted results indicate that the 0D homogeneous model is more predictive to the evolution of the DSD with high prediction accuracy. Both simplified 0D models are computationally cheap compared with time-consuming CFD simulations. The effects of the screen geometry, oil volume fraction, and operating conditions on the dispersion performance were also investigated.