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Tip vortex cavitation inception about an elliptical planform, NACA 0012 hydrofoil is investigated in cavitation tunnel flows in which cavitation nuclei are deplete and abundant. Tests were conducted at fixed Reynolds and cavitation numbers. The onset, or inception, of cavitation was induced by increasing the angle of incidence and behaviour was recorded photographically and acoustically. Cavitation inception occurred at a higher incidence in the deplete case compared with the abundant due to fewer weaker nuclei. It also occurred within a small incidence change for the deplete case, with the appearance of a continuous, cavitating vortical flow structure. Whereas for the abundant case, inception was intermittent, occurring across a larger incidence range. This was associated with individual nuclei activation events increasing in frequency with increasing incidence. Sound pressure levels increased with inception and cavity development but reduced to a local minimum once the cavity attached to the hydrofoil, increasing thereafter with incidence. Overall sound levels were higher for the abundant case than for the deplete case.

Item Type:	Refereed Conference Paper
Keywords:	tip vortex cavitation, inception, acoustic characterisation
Research Division:	Engineering
Research Group:	Maritime engineering
Research Field:	Ship and platform structures (incl. maritime hydrodynamics)
Objective Division:	Defence
Objective Group:	Defence
Objective Field:	Maritime
UTAS Author:	Khoo, MT (Mr Matthew Khoo)
UTAS Author:	Venning, JA (Dr James Venning)
UTAS Author:	Pearce, BW (Dr Bryce Pearce)
UTAS Author:	Brandner, PA (Professor Paul Brandner)
ID Code:	136212
Year Published:	2018
Deposited By:	NC Maritime Engineering and Hydrodynamics
Deposited On:	2019-12-06
Last Modified:	2020-01-30
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