Eulerian 2-Phase Flow in a Convergent-Divergent Channel

Eulerian Two-Phase Flow within a Convergent-Divergent Channel — ANSYS Fluent CFD Simulation

Description

Welcome to the Eulerian Two-Phase Flow within a Convergent-Divergent Channel CFD Simulation module. This project introduces fluid-fluid interactions in geometrically complex systems using the Eulerian multiphase model in ANSYS Fluent. A convergent-divergent channel changes cross-section along its length, so the two phases accelerate, decelerate, and redistribute as the area varies — a rich test of how the Eulerian model handles phase interactions and momentum transfer under changing flow conditions. The Eulerian model is the most detailed multiphase formulation, solving each phase separately, and applications range from nozzles and diffusers to heat exchangers and reactors. As the capstone of the Multiphase Flow: Beginner CFD Training Package, this project introduces the Eulerian model — the most advanced of the three multiphase approaches — in a geometrically demanding channel.

Methodology

The project uses a pre-configured convergent-divergent channel geometry representing a real flow system with varying cross-sectional areas, with a mesh built to capture the phase coupling within the complex geometry. Realistic boundary conditions are defined — flow rates, velocities, and phase fractions at the inlets and outlets, along with wall boundary conditions and roughness effects. The Eulerian model is central to the setup: the interfacial drag and lift models are selected and configured for the immiscible fluids, and turbulence modulation and phase-coupling effects are incorporated to govern the momentum exchange between phases. The case is solved as a steady-state simulation.

Analysis

Post-processing visualizes the phase fractions and velocity profiles through contours and vector plots along the channel, revealing how both phases move through the converging and diverging sections, with pressure drops and phase-separation tendencies quantified along the way. From these results you can investigate how the area changes affect the phase distribution and velocities, how the convergent-divergent angle influences flow patterns and separation, and where flow-regime transitions and critical zones for optimization occur. These insights connect directly to optimizing multiphase systems in complex geometries and enhancing heat transfer in two-phase equipment. By the end of this project, you'll be able to set up a two-phase Eulerian simulation in a variable-area geometry, configure interfacial drag, lift, and turbulence-modulation models, and interpret the phase-fraction, velocity, and pressure results that characterize Eulerian two-phase flow through a convergent-divergent channel.