OpenFOAM includes the following solvers for multiphase flows:

cavitatingFoam
Transient cavitation code based on the homogeneous equilibrium model from which the compressibility of the liquid/vapour “mixture” is obtained.
cavitatingDyMFoam
Transient cavitation code based on the homogeneous equilibrium model from which the compressibility of the liquid/vapour “mixture” is obtained.
compressibleInterFoam
Solver for 2 compressible, non-isothermal immiscible fluids using a VOF (volume of fluid) phase-fraction based interface capturing approach.
compressibleInterDyMFoam
Solver for 2 compressible, non-isothermal immiscible fluids using a VOF (volume of fluid) phase-fraction based interface capturing approach, with optional mesh motion and mesh topology changes including adaptive re-meshing.
compressibleMultiphaseInterFoam
Solver for n compressible, non-isothermal immiscible fluids using a VOF (volume of fluid) phase-fraction based interface capturing approach.
driftFluxFoam
Solver for 2 incompressible fluids using the mixture approach with the drift-flux approximation for relative motion of the phases.
interFoam
Solver for 2 incompressible, isothermal immiscible fluids using a VOF (volume of fluid) phase-fraction based interface capturing approach.
interDyMFoam
Solver for 2 incompressible, isothermal immiscible fluids using a VOF (volume of fluid) phase-fraction based interface capturing approach, with optional mesh motion and mesh topology changes including adaptive re-meshing.
interMixingFoam
Solver for 3 incompressible fluids, two of which are miscible, using a VOF method to capture the interface.
interPhaseChangeFoam
Solver for 2 incompressible, isothermal immiscible fluids with phase-change (e.g. cavitation). Uses a VOF (volume of fluid) phase-fraction based interface capturing approach.
interPhaseChangeDyMFoam
Solver for 2 incompressible, isothermal immiscible fluids with phase-change (e.g. cavitation). Uses a VOF (volume of fluid) phase-fraction based interface capturing approach, with optional mesh motion and mesh topology changes including adaptive re-meshing.
multiphaseEulerFoam
Solver for a system of many compressible fluid phases including heat-transfer.
multiphaseInterFoam
Solver for n incompressible fluids which captures the interfaces and includes surface-tension and contact-angle effects for each phase.
multiphaseInterDyMFoam
Solver for n incompressible fluids which captures the interfaces and includes surface-tension and contact-angle effects for each phase.
potentialFreeSurfaceFoam
Incompressible Navier-Stokes solver with inclusion of a wave height field to enable single-phase free-surface approximations
potentialFreeSurfaceDyMFoam
Incompressible Navier-Stokes solver with inclusion of a wave height field to enable single-phase free-surface approximations.
reactingMultiphaseEulerFoam
Solver for a system of any number of compressible fluid phases with a common pressure, but otherwise separate properties. The type of phase model is run time selectable and can optionally represent multiple species and in-phase reactions. The phase system is also run time selectable and can optionally represent different types of momentun, heat and mass transfer.
reactingTwoPhaseEulerFoam
Solver for a system of 2 compressible fluid phases with a common pressure, but otherwise separate properties. The type of phase model is run time selectable and can optionally represent multiple species and in-phase reactions. The phase system is also run time selectable and can optionally represent different types of momentun, heat and mass transfer.
twoLiquidMixingFoam
Solver for mixing 2 incompressible fluids.
twoPhaseEulerFoam
Solver for a system of 2 compressible fluid phases with one phase dispersed, e.g. gas bubbles in a liquid including heat-transfer.