Numerical study of phase split characteristics of slug flow at a branching micro‐T‐junction

Abstract

The phase split behavior of air-water slug flow at branching micro-T-junctions was studied by the volume of fluid model. The effects of velocity, surface tension, and viscosity on phase split results have been tested by slug units of fixed length. The split of a gas bubble at the T-junction shows obstructing and nonobstructing modes. Through comparison, we found that the appearance of tunnels changes the driving force of bubble breakup from upstream pressure to viscous shearing force. Split features are influenced by the length of slug unit and the flow ratio in the obstructing mode. Nevertheless, the viscous force and surface tension should not be slighted for nonobstructing mode. Moreover, tendency of the flow maldistribution of nonobstructing mode is more pronounced with higher velocity and smaller surface tension. The liquid slug length has a negligible effect on the split results of gas phase. Thus, the results of two-phase split could be obtained from the gas split ratio solely. Pattern diagram for the transition between the 2 modes was proposed. Eventually, the importance of the length information of slug unit was also verified by the predictive model of phase split that formulated with the regression analysis of numerical data.

Modelling and analysis of impact forces acting on elbow in gas–liquid slug flow

“…The variable v s is the mixture velocity of the slug and can be calculated by ( v sl + v sg ). The drift velocity v d in the horizontal and upward inclined pipe was proposed by Bendiksen as follows: …”

Numerical investigation of bubble breakup in a four‐branched microchannel based on non‐Newtonian pseudoplastic fluid

“…Different methodologies for the numerical modeling bubble dynamics in gas-liquid two-phase flow have been explored by the volume-of-fluid (VOF) method, 26,27 level set (LS) method, 28,29 and lattice Boltzmann method. Different methodologies for the numerical modeling bubble dynamics in gas-liquid two-phase flow have been explored by the volume-of-fluid (VOF) method, 26,27 level set (LS) method, 28,29 and lattice Boltzmann method.…”

“…Recently, numerical simulation method has become an increasingly popular approach due to its high capability to acquire some detailed information on velocity fields, as well as allow the control of all process variables. Different methodologies for the numerical modeling bubble dynamics in gas-liquid two-phase flow have been explored by the volume-of-fluid (VOF) method, 26,27 level set (LS) method, 28,29 and lattice Boltzmann method. 30,31 Sussman and Puckett 32 compared the coupled LS and VOF (CLSVOF) method with the LS method, the VOF method, and the boundary integral method and verified that this coupled method was superior to VOF or LS alone.…”