Direct numerical simulation of two-phase pipe flow: Influence of the domain length on the flow regime. (November 2021)

• Record Type: Journal Article
• Authors: Plana, Carlos; Song, Baofang; Avila, Marc
• Is Part Of: International journal of multiphase flow. Volume 144(2021)
• Publication Date: 2021-11
• Subjects: Phase-field method -- Core-annular flow -- Hydrodynamic stability -- Turbulent multiphase flow; Multiphase flow -- Periodicals; Écoulement polyphasique -- Périodiques; Multiphase flow; Periodicals; 620.1064
• DOI: 10.1016/j.ijmultiphaseflow.2021.103786
• Languages: English
• ISSNs: 0301-9322

Abstract

Abstract: We investigate the dynamics of a kerosene–water mixture in a vertical pipe flow by solving the Cahn–Hilliard–Navier–Stokes equations. We compute the linear stability of laminar core-annular flow in a vertical pipe and find that it is highly unstable. By performing direct numerical simulations initialized with a slightly perturbed core-annular flow, we show that the system transitions to turbulence and finally relaxes into a turbulent slug flow regime provided that the pipe is sufficiently long. This configuration presents mild turbulence and large scale three-dimensional recirculation patterns. Our work highlights the need for applying nonlinear-dynamics approaches and carefully selecting the domain length to investigate the patterns observed in two-phase pipe flows and demonstrates the capabilities of phase-field methods to reliably simulate flows under realistic experimental conditions. Highlights: Simulation of kerosene–water pipe flow using phase-field method. Slug flow configuration stable; water drops stable in isolation. Chaotic recirculation patterns inside the slug structures. Turbulence intensity sensitive to interface thickness; flow patterns unchanged.