Results 101 to 110 of about 524 (131)

Tip Leakage and Backflow Vortex Cavitation

2007
In addition to blade surface cavitation, tip leakage and backflow cavitations occur in real inducers. Although most of cavitation instabilities can be explained by considering only blade surface cavitation, these types of cavitation might play an important role especially for the suppression of instabilities.
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Large Eddy Simulations of cavitating tip vortex flows

Ocean Engineering, 2020
In the current study, tip vortex flows are numerically studied by employing Large Eddy Simulation. Wet flow, cavitation inception, and cavitating tip vortex simulations are carried out on an elliptical foil. The mesh resolution requirements for tip vortex prediction are evaluated by employing different mesh resolutions.
Abolfazl Asnaghi, Urban Svennberg, Rickard E. Bensow   +2 more
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On the physical mechanism of tip vortex cavitation hysteresis

Experiments in Fluids, 2019
Inception and desinence thresholds of tip vortex cavitation (TVC), generated by an elliptical NACA 16-020 hydrofoil, are measured at different flow conditions for various gas contents. It is observed that TVC often disappears at cavitation indices significantly higher than the inception thresholds introducing large hystereses.
Ali Amini, Martino Reclari, Takeshi Sano, Masamichi Iino, Matthieu Dreyer, Mohamed Farhat   +5 more
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Compressive spherical beamforming for localization of incipient tip vortex cavitation

The Journal of the Acoustical Society of America, 2016
Noises by incipient propeller tip vortex cavitation (TVC) are generally generated at regions near the propeller tip. Localization of these sparse noises is performed using compressive sensing (CS) with measurement data from cavitation tunnel experiments. Since initial TVC sound radiates in all directions as a monopole source, a sensing matrix for CS is
Youngmin, Choo, Woojae, Seong
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Effect of Hydrofoil Planform on Tip Vortex Roll-Up and Cavitation

Journal of Fluids Engineering, 1995
The effect of the planform of hydrofoils on tip vortex roll-up and cavitation has been investigated by testing three foils having the same NACA 16020 cross section but different shapes. One foil has an elliptical shape while the other two are shaped like quarters of ellipses; one with a straight leading edge and the other with a straight trailing edge.
Fruman, D H, Cerrutti, Ph, Pichon, Th, Dupont, Philippe   +3 more
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Dynamic hysteresis process in tip vortex cavitation

Physics of Fluids
In this Letter, experiments are conducted on tip vortex cavitation (TVC) over a stationary elliptical hydrofoil with the cross section of NACA (National Advisory Committee for Aeronautics) 662−415 in a water tunnel. The state of TVC at various cavitation numbers, inflow velocities, and angles of attack is tested.
Jing-Wei Jiang, Chun-Mei Xie, Da-Zhuan Wu, Zheng-Fang Qian, Liang Li, Liang-Hao Xu, Wei-Xi Huang   +6 more
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Effect of Polymer Solutions on Tip Vortex Cavitation

1985
The effect of polymer solutions, ejected at very small flow rates at the tip of a finite span hydrofoil, on the inception and extent of tip vortex cavitation is investigated. The results show that the dessinent cavitation numbers are significantly reduced by polymer additives as compared with those in pure water. Moreover, for operating conditions well
D. H. Fruman, D. Bismuth, S. Aflalo
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A note on the scaling of tip vortex cavitation inception

International Shipbuilding Progress, 1977
A rule for scale effects on tip vortex cavitation inception is derived. With help of this rule full-size tip vortex cavitation inception can be predicted from model tests. The rule is illustrated by means of a few test results.
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A study on the numerical prediction of propellers cavitating tip vortex

Ocean Engineering, 2014
The problem of the tip vortex cavitation inception is a matter of increasing interest. Main reason for this is that, despite being, generally, not erosive and not influent on the propeller mechanical characteristics, the cavitating vortex dynamics may play a significant role in the propeller radiated noise.
GAGGERO, STEFANO, TANI, GIORGIO, VIVIANI, MICHELE, F. Conti   +3 more
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Propeller Tip Vortex Cavitation Noise Inception

SNAME Propellers '81 Symposium, 1981
The recent concern for reducing ship noise has resulted in the necessity of treating propeller cavitation noise. In this paper a review of the work on tip vortex cavitation is used to begin a discussion of propeller hub and tip vortex cavitation noise. Model propeller noise measurements are used to characterize hub and tip vortex cavitation noise.
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