High-speed visualization of cavitation evolution around a marine propeller
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Nowadays, a lot of types of digital high-speed video camera are available with a wide range of image rates. The new camera technology has made it possible to observe the cavitation on a propeller. However, until recently cavitation on ship propellers is observed visually using the so-called time-lapse observations. The conventional time-lapse method cannot accurately detect the temporal development of cavitation. High-speed video visualizes the complete process of cavitation. A high-speed video system was developed to observe the cavity dynamics in more detail in a more reliable way. This paper shows the high-speed visualization results of a cavitating propeller, which give a better recording of the complete cavitation dynamics. Appropriate post-processing of the obtained high-speed images enables the detailed illustration of the interface topology of the propeller cavitation, and the weak tip vortex cavitation which is not readily apparent to the naked eyes can be detected by the edge-detection methodology. This can be used to explain the major discrepancies between acoustic criterion and optical criterion of detection of cavitation inception, which are known to provide different answers in the most practical applications.
KeywordsPropeller Cavitation High-speed video Phase congruency method
The authors appreciate the valuable comments of the anonymous referees. This work was supported by the National Natural Science Foundation of China (NSFC) under Grant No. 11502240. This work was also supported by Equipment Pre-research Foundation of China (Grants No. 41407020501).
- Canny JF (1983) Finding edges and lines in images. Master’s thesis, MIT. AI Lab. TR-720Google Scholar
- Copalan S, Liu HL, Katz J (2000) On the flow structure, tip leakage cavitation inception and associated noise. In: 23rd Symposium on naval hydrodynamicsGoogle Scholar
- Godefroy V, Fréchou D, Desvignes M, Bloyet D (1998) Digital image processing for cavitation on marine propellers. In: Third international symposium on cavitationGoogle Scholar
- Hoshino T, Jung J, Kim JH, Lee JH, Han JM, Park HG (2010) Full scale cavitation observations and pressure fluctuation measurements by high-speed camera system and correlation with model test. In: International propulsion symposiumGoogle Scholar
- Kovesi P (1995) Image features from phase congruency. Tech Rep 95/4. University of Western AustraliaGoogle Scholar
- Pringle KK (1969) Visual perception by a computer. In: Grasselli A (ed) Automatic interpretation and classification of images. Academic Press, New York, pp 277–284Google Scholar
- Tukker J, Kuiper G (2004) High-speed video observations and erosive cavitation. In: Proceedings of 9th symposium on practical design of ships and other floating structures, pp 941–948Google Scholar
- Venkatesh S, Owens RA (1989) An energy feature detection scheme. In: The international conference on image processing, pp 553–557Google Scholar