multiphaseInterFoam - OpenFOAM Solver

Solver: multiphaseInterFoam   Description

multiphaseInterFoam is a solver designed for transient simulations involving two or more incompressible, isothermal, and immiscible fluids. It is based on interFoam and extends its capabilities to systems with three or more phases. The solver can handle both laminar and turbulent flows and is compatible with Newtonian and non-Newtonian fluids. Similar to its predecessor, it employs the Volume of Fluid (VoF) method to accurately capture the interface between the fluids.

The solver utilizes the PIMPLE algorithm, a combination of the PISO and SIMPLE methods, for pressure-momentum coupling. This algorithm integrates the strengths of both methods to ensure robust handling of transient flows with large time steps. Under-relaxation techniques are applied to enhance convergence stability. The MULES algorithm is used to ensure that phase fractions remain bounded and interfaces sharp. The solver also supports Multiple Reference Frames (MRF), porosity modeling and allows for the easy integration of passive scalar transport equations and source terms. It is capable of handling dynamic meshes.

The solver is particularly useful in scenarios requiring the simulation of three or more phases. Examples include environmental flows, where the transport of pollutants is a concern. In the oil industry, it can simulate the mixture of oil, water, and air encountered during extraction processes. Other applications include nuclear reactors and microfluidics.

Solver: multiphaseInterFoam   Features

  • Transient
  • Incompressible
  • Multiphase - Volume of Fluid (VoF)
  • Multiple Immiscible Fluids
  • Dynamic Mesh Motion
  • Laminar and Turbulent (RANS, LES, DES)
  • Newtonian and Non-Newtonian Fluid
  • Pressure-Based Solver
  • Rotating Objects:
    • Multiple Reference Frames (MRF)
    • Rotating Mesh Motion
  • Passive Scalar
  • Porosity Modeling
  • Buoyancy
  • Source Term (explicit/implicit)
  • PIMPLE Algorithm
  • MULES Algorithm
  • Solution Limiters:
    • Velocity Damping

Solver: multiphaseInterFoam   Application

Environmental Flows

  • River Pollution - water, sediment and air phases
  • Microreactors for Chemical Synthesis - Microfluidics

Industrial Chemistry

  • Reactors Columns
  • Mixing and Stirring Tanks

Energy Industry

  • Nuclear Reactors
  • Oil Extraction

Solver: multiphaseInterFoam   Multiphase - Free Surface (VoF) Solvers

Free Surface (VoF) Solvers In this group, we have included solvers implementing Volume of Fluid (VoF) approach to handle multiple immiscible and miscible fluids and interactions between them.

Free Surface (VoF) - Immiscible

Free Surface (VoF) - Miscible

  • * isoAdvector - an alternative approach for interface capturing, MULES method used in other VoF solvers
  • ** Solver designed to handle mixtures consisting of multiple fluids within the same phase, such as two gases or two liquids
  • VoF - Volume of Fluid
  • DyM - Dynamic Mesh
  • Overset - also known as Chimera Grid (Method)

Solver: multiphaseInterFoam   Alternative Solvers

In this section, we propose alternative solvers from different categories, distinct from the current solver. While they may fulfill similar purposes, they diverge significantly in approach and certain features.

Solver: multiphaseInterFoam   Tutorial

  • Analysis involving 3-phase flow of immiscible fluid. The simulation models the movement of mud in water after the gate is opened, considering the presence of air above them.

Solver: multiphaseInterFoam   Results Fields

This solver provides the following results fields:

  • Primary Results Fields - quantities produced by the solver as default outputs
  • Derivative Results - quantities that can be computed based on primary results and supplementary models. They are not initially produced by the solver as default outputs.

Primary Results Fields


\(U\) [\(\frac{m}{s}\)]

Phase Volume Fraction

\(\alpha\) [\(-\)]

Hydrostatic Perturbation Pressure

\(p - \rho gh\) [\(Pa\)]

Hydrostatic Perturbation Pressure This value represents the pressure without the hydrostatic component (minus gravitational potential). Read More: Hydrostatic Pressure Effects

Derivative Results


\(P\) [\(Pa\)]


\(\rho\) [\(\frac{kg}{m^{3}}\)]


\(\omega\) [\(\frac{1}{s}\)]

Courant Number

\(Co\) [\(-\)]

Peclet Number

\(Pe\) [\(-\)]

Stream Function

\(\psi\) [\(\frac{m^2}{s}\)]

Q Criterion

\(Q\) [\(-\)]

Wall Functions (for RANS/LES turbulence)

\(y^+\) [\(-\)]

Wall Shear Stress

\(WSS\) [\(Pa\)]

Turbulent Fields (for RANS/LES turbulence)

\(k\) \(\epsilon\) \(\omega\) \(R\) \(L\) \(I\) \(\nu_t\) \(\alpha_t\)

Volumetric Stream

\(\phi\) [\(\frac{m^{3}}{s}\)]

Passive Scalar

\(scalar_i\) [\(-\)]

Forces and Torque acting on the Boundary

\(F\) [\(N\)] \(M\) [\(-\)]

Force Coefficients

\(C_l\) [\(-\)] \(C_d\) [\(-\)] \(C_m\) [\(-\)]

Average, Minimum or Maximum in Volume from any Result Field

\(Avg\) \(Min\) \(Max\)