ΜΕ24 | Multiphase Flows

Postgraduate Study Program | Power Systems

General Features of Multiphase Flows: Fundamental definitions. Volume fraction and densities. Superficial and phase velocities, quality, concentration, and loading. Dispersed phase and separated flows. Two-phase flow of gas–liquid, gas–solid, liquid–solid. Three-phase flows.

Pneumatic Conveying of Solids: Homogeneous and separated flow. Calculating pressure drop. Designing conveying systems. Separation of phases. Separation efficiency, gas–solid separation, liquid–solid separation.

Gas-Liquid Two-Phase Flows: Two-phase pressure drop. Homogeneous model. Lockhart–Martinelli correlation. The flow-pattern-dependent method. Bubble flow, Intermittent (Slug and Churn) flow, Stratified, Stratified Wavy, Annular flow. Calculation algorithm for flow pattern determination.

Air-Lift Pump: Mathematical modelling. Operational characteristic curves. Parametric investigation of the influence of the pipe diameter, injection depth, diameter and density of the particles in the operational curve of the pump.

Flow Through Porous Media: Porosity, Permeability. Capillarity in porous media. Capillary Pump Loop (CPL). Steady multiphase flow in porous media. Gas–liquid two-phase flow in microchannels. Two-phase flow patterns, void fraction, pressure drop.

Computational Modeling of Multiphase Flows: Continuous-phase and Particle-phase flow methodologies. Continuous-phase equations. Mass conservation, momentum conservation, energy equation. Turbulence equations. Dispersed phase equations. Lagrangian and Eulerian approach. Applications.

Multiphase Flow Measurements: Mass flow measurements. Velocity measurement. Liquid flow measurement in gas–liquid flows. Measurements of particulate mixtures. Laser Doppler Velocimetry (LDV). Particle Image Velocimetry (PIV). Applications.