An open source code for two-phase rarefied flows: rarefiedMultiphaseFoam

This paper presents the development and benchmarking tests of an open source code for providing solutions of two-phase rarefied flows. The solver is named in rarefiedMultiphaseFoam and it is developed in OpenFOAM, based on dsmcFoamPlus, which is used for the rarefied gas phase. The solver can produce both steady and transient results for arbitrary 2D/3D two-phase rarefied flows and includes a phase change model for materials that experience melting and solidification processes. The benchmarking tests include momentum and heat exchange between gas phase and solid phases, particle phase change, a converging nozzle that creates a solid particle beam, and transport of solid particles. The tests yield good agreement with analytical and experimental data where available, and are compared to previous numerical results from the literature.