A MultiPhase Dynamic-VoF solver to model primary jet atomization and cavitation inside high-pressure fuel injectors in OpenFOAM

This paper describes the development of a dynamic multiphase Volume-of-Fluid (VOF) solver to study the physics of the primary jet breakup and flow transients induced by the nozzle geometry during the injector opening event in high-pressure injection using the OpenFoam technology. The dynamic solver supports moving meshes with large deformations and topological changes and hence ideally suited for the problem under consideration. The compression and the advective term in the transport equation of the void fraction in the VOF solver have been reformulated to ensure proper conservation of the fluid-dynamic quantities in moving mesh problems and are second order accurate in time with automatic topology changes. The solver has also been extended to include the curvature effect in the interface tracking and it has been coupled with submodels for cavitation. While the solver is compatible with any kind of turbulence model, turbulence effect have been treated using Large-Eddy Simulations (LES) in the present work. Detailed numerical studies are presented to ensure the conservation preservation property and accuracy of the solver. Furthermore, flow simulations of a practical injector, namely, a Continental XL 3.0 6-hole prototype injector were conducted and the results compared with experiments.