Broadband pressure fluctuations induced by tip vortex cavitation (TVC) instabilities pose significant challenges to the safe operation of marine propulsion systems, yet the underlying mechanisms remain poorly understood. To explore these mechanisms, this study employs an Euler-Lagrange hybrid model and develops an analytical model to quantify the instability intensity. Bubble-type vortex bursting is identified as the primary mode of instability under both wetted and cavitating conditions. In wetted conditions, instability intensity correlates strongly with the blade load variation, while in cavitating conditions, it decreases due to the reduced load variation. Nevertheless, sharp pressure rise in the bursting vortex core can still trigger intense TVC instability. This instability satisfies the zero-group-velocity condition, giving rise to significant broadband pressure fluctuations near the corresponding characteristic frequency. These findings provide insights for controlling flow instabilities in marine propulsion.

Close

PrevNext

View figure in article

• Cavitation
• Flow instability
• Multiphase flows
• Vortex dynamics