Information is organized into the following subsections:

• 14.4.1. Overview
• 14.4.2. Limitations of the Mixture Model
• 14.4.3. Continuity Equation
• 14.4.4. Momentum Equation
• 14.4.5. Energy Equation
• 14.4.6. Relative (Slip) Velocity and the Drift Velocity
• 14.4.7. Volume Fraction Equation for the Secondary Phases
• 14.4.8. Granular Properties
• 14.4.9. Granular Temperature
• 14.4.10. Solids Pressure
• 14.4.11. Interfacial Area Concentration
• 14.4.12. Flow Regime Modeling