Saraswat, AyushAyushSaraswatPanigrahi, ChintanChintanPanigrahiKatz, JosephJosephKatz2024-04-152024-04-152024-04-048th International Symposium on Marine Propulsors (smp 2024)978-82-691120-5-4https://hdl.handle.net/11420/46457This paper presents results from high-speed visualization of tip leakage cavitation in a two-bladed ducted marine propeller. The observations highlight the cavitation around the blade tip. Included are: (i) traveling bubble cavitation in the tip gap, (ii) cavitation in the tip leakage vortex (TLV) that rolls up on the blade suction side (SS), (iii) and cavitating secondary structures engulfed from the blade pressure side (PS) to the SS. The secondary vortex filaments originate either from the pressure side of the blade or in the case of low advance ratios, from remnants of the TLV generated by the previous blade. As these filaments cross the tip gap, they are typically oriented perpendicularly to the blade chord. While being entrained, they appear to be associated with kinks or meandering of the TLV trajectory in the aft part and downstream of the blade, eventually resulting in TLV breakup. In all cases, cavitation inception appears as intermittent local elongated events along the TLV, typically in the aft part of the passage, hence away from the blade surface. At the same advance ratio, upon reduction in pressure, first the entire TLV core becomes filled with cavitation, which then expands to secondary structures and causes earlier kinking of the TLV. With further reduction in pressure, traveling bubble cavitation develops in the tip gap, filling the region between the TLV and the blade SS with cavitation, resulting in fragmentation of the TLV and formation of large cavitating vortices oriented in multiple directions. At the same cavitation index, with decreasing advance ratio, the cavitation in the TLV core thickens and starts closer to the leading edge, the vortex migrates farther from the blade SS, and starts meandering and breaking up early, presumably under the growing influence of more intense secondary vortices. Hence, both the advance ratio and the extent of cavitation alters the TLV trajectory, shape, and breakup.enhttp://rightsstatements.org/vocab/InC/1.0/Ducted propellercavitationhigh-speed imagingtip leakage vortexEngineering and Applied OperationsConference Paper10.15480/882.932010.15480/882.932010.15480/882.9294Conference Paper