TwoPhaseFlow: A Framework for Developing Two Phase Flow Solvers in OpenFOAM

We present a new OpenFOAM based open-source framework, TwoPhaseFlow, enabling fast implementation and testing of new phase change and surface tension force models for two-phase flows including interfacial heat and mass transfer. Capitalizing on the runtime-selection mechanism in OpenFOAM, the new models can easily be selected and benchmarked against analytical solutions and existing models. The framework currently includes the following three interface curvature calculation methods for surface tension: 1) the height function method, 2) the parabolic fit method and 3) the reconstructed distance function method.  As for phase change, two models are available: 1) Interface heat resistance and 2) direct heat flux. These can be combined in three solvers: 1) InterFlow for isothermal, incompressible two-phase flow, 2) compressibleInterFlow for compressible, non-isothermal two-phase flow and 3) multiRegionPhaseChangeFlow for compressible, non-isothermal two-phase flow with conjugated heat transfer. By design, addition of new models and solvers is straightforward and users are encouraged to contribute their specific models, solvers, and validation cases to the library.