Numerical assessment of performance characteristics and two-phase flow dynamics of a centrifugal rotor operating under gas entrainment condition

Abstract

This work presents a numerical study of performance characteristics and flow dynamics of a centrifugal rotor operating with gas-liquid flow. An Euler-Euler polydispersed model is adopted, which was validated in a previous publication and is used in this work to assess quantities not addressed in the earlier study. An analysis of the rotor performance under two-phase is performed, for which suitable expressions are presented. In particular, an analysis of the rotor head components is carried out including the dynamic head evaluation through the rotor, which is often neglected in most studies. The numerical model is explored further to analyze flow patterns and relevant gas-liquid flow quantities. This includes analysis of the three-dimensional distribution of the gas phase inside the rotor, evaluation of gas-liquid interphase forces, and the effect of the intake gas flow rate on the bubble diameter, gas-liquid relative velocities, and the overall turbulence levels through the rotor. Such analyses, which are usually hard to obtain through experimental methods, are also rarely found in related numerical studies. Thus, this work could bring useful information to help in the understanding of the gas-liquid flow behavior in centrifugal rotors, while also contributing to the progress of numerical solution of this problem.