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A novel multiphase Volume-of-Fluid (VOF) solver to model the physics of the internal nozzle flow and primary jet
breakup in high-pressure injection is presented. The solver includes extensions to cavitation modeling to support
phase change in presence of three phases (fuel-vapour, fuel-liquid and non-condensable gases), that are tracked
in a single-fluid framework. The solver also supports dynamic mesh handling, either based on cell deformation
or on topological changes and it is able to preserve second-order accuracy in time and space. It is shown that
the tracking of the air/vapour interface is able to capture phenomena such as the hydraulic flip and the string
cavitation. Code validation is carried out on two transparent glass nozzle geometries, especially developed by
Continental Automotive SAS for detailed comparison of experiments and high-fidelity LES simulations. Data analysis
is performed to understand how the vorticity dynamics is linked to the cavitation and atomization process to find a
correlation with the vapor production. The proposed approach favors an accurate track of the evolution of the
different phases within the nozzle hole and a very detailed description of the vortex generation in the injector nozzle,
in presence of primary atomization of the jet. Moreover, the implemented phase-change model is able to predict how
vorticity and cavitation develops within the nozzle and their influence on the atomization process. The developed
code is included in a C++ Object-Oriented Library developed by the authors at PoliMi/DAER, that is linked to the
most recent releases of OpenFOAM.
