| Item | Mechanisms | Variables/Model Parameters |
|---|---|---|
| A | Inertia forces |
 (velocity and diameter) 
|
| B | Pressure forces |
 or Re/mix viscosity  (pressure, density and diameter) 
|
| C | Viscous forces |
 (kinematic viscosity, velocity and diameter) Re/inertia forces |
| D | Gravitational forces | ϕ'g, εg, and θg |
| E | Momentum and molecular diffusivities | η and D (kinematic viscosity and diffusion coefficient) |