Abstract
Unsteady non-cavitating and cavitating flows of submerged water jet have been investigated numerically by applying a practical approach based on two-phase cavitating flow model. Computations were focused on the behavior of starting submerged jet, and the validity was confirmed by comparing computational results with experimental data. Numerical results reveal that a ring-like starting vortex is generated around the jet periphery with impulsively starting of submerged water jet. Independent of the injection velocity the development of ring-like starting vortex is decided by the vortex formation time. When the device cavitation coefficient is smaller than a certain value cavitations take place initially in the local area of starting vortex core, and a ring-like cavity of cavitation bubbles is generated. The behavior of the ring-like cavity is closely related to the development of starting vortex, which is influenced by cavitation bubbles in turn.
