Simulation of dispersion of stabilized Water droplets in a turbulent oil flow through a horizontal tubing

Abstract

Dispersion of two immiscible fluids in a horizontal turbulent pipe flow is simulated with the developer’s version of the STAR-CCM+® CFD code of Siemens PLM. Formation of a stable (no coalescence) dilute water in oil emulsion is analyzed. The Reynolds stress turbulence model in combination with the Daly & Harlow transport model are employed for modeling a three-dimensional flow. The CFD - population balance method, available within the code, is a basis for computations. A model of the droplet shear dispersion phenomenon that we incorporated into the code allows to properly account for formation of an enhanced droplet concentration area in the pipe bottom vicinity. In the computations conducted, each droplet size fraction is characterized by its own velocity, whereas majority of 3-D population balance computations known from open literature have been done by a simplified approach assuming a single average velocity. The major peculiarities of droplet dispersion in a horizontal pipe flow are illustrated by numerical examples.