... The paper discusses some of the more complex cavitation structures that have been encountered in full-scale ship practice and the integration that has been observed to occur between the various substructures of the cavitating regimes. Some comparison with model scale studies is made. The paper...

... larger propellers are attractive to the boat builder. This paper examines the effects of propeller tunnel applications on propeller cavitation I vibration characteristics as compared to more traditional non-tunnel configurations. Propeller induced excitation levels are calculated for a systematic series...

... This paper provides results of full-scale video observations of underway cavitating propeller operation and corresponding vibration acceleration measurements taken in the stem region of the U.S. Coast Guard Seagoing Buoy Tender WLB 201 JUNIPER. Selected results are presented from two different...

.... The variability of these quantities are observed with PIV and the average quantities are compared between LDV and PIV. Developed cavitation is also examined for the leakage vortex. The implication of vortex variability on cavitation inception is discussed. 1 PIV MEASUREMENTS OF A TIP LEAKAGE VORTEX Carolyn Q...

... An electrical impedance probe is used to study the properties of partial attached cavitation. The method uses a series of electrodes mounted flush to the surface of a cavitating hydrofoil to obtain ti.me-dependent information about the presence of liquid or vapor in the region of interest...

... Laminate construction technology is used to reduce the local angle of attack at the tip of an elliptic foil to delay the inception of tip vortex cavitation. As the angle of attack is increased on the foil, the increased lift causes the tip to flex in a direction that relieves the hydrodynamic...

... hydraulic jet pump cavitation waterjet propulsion figure 4 figure 2 cavitation inception inlet cavitation tunnel semi-flush inlet geometry stricker multiphase pump npsh inlet efficiency cavitate diameter thrust artificial lift system efficiency ingestion figure 1 model...

... Rudder surfaces can experience severe cavitation at high speeds or in hard turns resulting in excessive noise, vibration and erosion. Methods to improve surface ship rudder performance are being investigated at David Taylor Model Basin. As part of this project, effects of cavitation on rudder...

... A computational method (HPUF-3A) for the prediction of unsteady propeller blade sheet cavitation is applied to the analysis of supercavitating propellers in steady flow. The method is incorporating a vortex and source lattice scheme. To allow for the treatment of very long supercavities...

... This paper presents a method to design foil sections for marine propellers or hydrofoils using inviscid and boundary-layer theory. The current configuration allows a variety of goals and constraints including cavitation inception prediction, lift/drag maximization, and flow separation avoidance...

...CAV:ITATION AND MULTIPHASE FLOW LABORATORY AT THE UNIVERSITY OF MICHIGAN by Darin L. George Steven L. Ceccio, Ph.D. Department of Mechanical Engineering and Applied Mechanics The University of Michigan ABSTRACT The Cavitation and Multiphase Flow Lab at the University of Michigan employs two water...

... efficiency of 6-7% was achieved. The second application is a backfit to a high speed U.S. Coast Goard pa­ trol boat. The purpose of this design is to eliminat severe cavitation erosion near the root of the existing propeller. A small span asymmetric stator is designed to operate with the existing propeller...

... Several experiments performed by Ceccio and Brennen ( 1991, 1989) and Kumar and Brennen 1992, 1991) have closely examined the interaction between individual cavitation bubbles and the boundary layer, as well as statistical properties of the acoustical signals produced by the bubble collapse...

... A propeller design procedure incorporating new propeller blade sections has been developed to improve propeller cavitation inception. Two dimensional foil design procedures of Shen and Eppler provide geometry for a specified blade pressure distribution. Advanced propeller lifting surface design...

... Selective injection of a drag-reducing polymer solution into the tip vortex region of the blades of an 11.5 inch diameter propeller is seen to be effective in significantly delaying tip vortex cavitation. For well positioned injection ports, the cavitation number at inception was decreased...

...Numerical vs. Experimental Cavitation Tunnel (A supercavitating hydrofoil experiment) S.A. Kinnas, C.H. Mazel (Massachusetts Institute of Technology, USA) Abstract A supercavitating hydrofoil experiment is performed at the MIT Variable Pressure water tunnel, at several an­ gles of attack...

... The tip vortex roll-up process from an elliptic wing was experimentally investigated. Cavitation provided an excellent method for visualizing the mechanism of vortex roll-up. The velocity profiles of the non-cavitating vortex were first obtained with a laser Doppler velocimeter. The measured...

... In order to investigate the character of cavitation inception from rotating rods, a series of experiments were performed in the 5000x450x450 mm test section of the University of Tokyo Propeller Cavitation Tunnel. This paper presents a summary of the experimental design, a comparison...

... cavitation A DESIGN METHOD AND AN APPLICATION FOR CONTRARO TATING PROPELLERS Benjamin Y.-H. Chen and Arthur M. Reed David Taylor Research Center, Bethesda, MD 20084, U. S. A. ABSTRACT A design methodology for contrarotating propellers bas been developed based on rational hydromechanics. Three fundamental...

... Eyretechnics Ltd. Suite 207, 11 Morris Dr. Dartmouth, Nova Scotia, Canada D3D lM:2 Abstract Propeller viewing trials are a necessary adjunct to towing tank and cavitation tunnel tests, if a full assessment of propeller performance is to be made. Unfortunately, viewing trials are rare because of the expense...