Unsteady behavior of cloud cavitation and its induced shock waves: Part 2: Two-dimensional multiphase flow analysis

We conducted a two-dimensional numerical analysis on the unsteady behavior of cloud cavitation and associated induced shock waves using the smoothed particle hydrodynamics method in conjunction with a pulsed submerged water jet injection into still water through a nozzle. We modeled a bubbly water jet as a mixture of liquids and gases to develop Navier–Stokes (NS) equations for multiphase flows in the Lagrangian description, which can naturally describe the inception of cavities without phase change models or initial bubble conditions. Subsequently, we numerically investigated the inception, growth, collapse, and rebound of clouds generated in multiphase flows. Our investigation revealed the appearance of twin vortices in association with the water jet injection, which moves along the boundary of the cloud synchronized with its growth and collapse behavior. Furthermore, we investigated the pressure fields to showcase the emission of the shock wave associated with the cloud collapse, noting the release of weak pressure waves prior to the main shock wave generation. Finally, a comparative study between the numerical analysis and the experimental results outlined in Part 1 of this study demonstrated consistency in the numerically observed unsteady behavior of the cloud and main shock wave phenomenon.