# Multiphase flow modeling methods

In modeling methods, several methods for modeling multiphase flows can be used. The suitability of the method depends on the nature of the multiphase flow and the physical properties involved.

#### Simplified multi-component methods:

In these approaches for modeling the multiphase flow of the model equilibrium is used because it assumes that mass transfer occurs very quickly. Volumetric components are obtained using algebraic terms based on the energy of the mixture and the enthalpy of steam and liquid. Mixed properties are calculated using volumetric masses and fluid properties. In this method, particles are assumed to be small, and only the drag force is considered.

#### Fully multiphase Analysis:

To simulate using these approaches, there are two main methods of Euler-Euler and Euler-Lagrangian. In the Euler-Euler method, the transfer equations are written separately for all phases, but in the Euler-Lagrangian method, the transmission equations for the continuous phase are solved, and for the dispersed phase only the path of the particles is detected by the Lagrangian.

#### Eulerian-Eulerian Approach:

Phases are mixed on a larger scale than molecules. However, the mixing process occurs at smaller scale than the network size. Each phase assumes that the volume of control is occupied, and the volume of the partial phases is equal to the volume of the occupied cells. Volume masses are obtained by solving the continuity equations for each phase. In general, each phase has its own field variables. Variables that are assumed to be homogeneous are shared between phases. Phases are linked by interphases models for energy, additional variables (mass), and momentum transfer. Inter-phase models are provided using empirical inputs to solve the problem. In the more elaborate way, the continuous, momentum, energy for each phase must be solved. By writing the equations of the N series, the partial differential equation is obtained by coupling.

To simulate, there are two homogeneous and non-homogeneous approaches. In the homogeneous approach all field variables are shared except for the volume component between phases, but in the non-homogeneous method, only the pressure between the phases is shared.