... of the perfect and defective sections. Leading-edge defects of 0.5 mm and 0.25 mm were investigated. These defects were shown to affect cavitation inception significantly and detrimentally. shipbuilding defect tunnel cavitation tunnel reduction marine transportation canada government cavitation...

... model scale transverse kinetic energy loss energy flux marine transportation resistance non-uniformity loss reduction axial kinetic energy flux propeller propeller series On the Selection of Optimal Propeller Diameter for a 120m Cargo Vessel Jennie Andersson1 (V), Robert Gustafsson2 (V...

... are shown in Figure 13. Friction Torque [Nm] 8 6 12 Clean 4 Clean Friction Torque [Nm]10% Water 2.5% Water 2 5% Water 10 10% Water 0 1234 8 0 56 Bearing Load [MPa] 6 Fig. 10 Friction Torque for Mineral oil ISO VG68 4 It can be seen from Figure 10 that there is an insignificant 2 reduction in the friction...

... thrust bearing supplied for the Japanese Techno Super Liner project are also presented. friction simmons operation journal pad lbf break away babbitted pad mpa reduction hydrodynamic bearing thrust bearing coefficient application thrust pad thrust collar ptfe thrust block babbitt...

... and 1.8 times that allowed. As a result, the vessels were being limited to approximately 80% of rated power with an attendant 0.7 kt reduction in operating speed. After reviewing the given application, Bird-Johnson Company decided to propose a custom propeller design to the U.S. Army . The goal of the new...

... procedure cavitation side cavitation prediction cavitation inception reduction propeller calculation pressure distribution camber distribution loading bladed propeller variation geometry camber erosion PROPELLER DESIGN AND EVALUATION FOR A HIGH SPEED PATROL BOAT INCORPORATING ITERATIVE...

... carriers built by Jiang Nan shipyard and have obtained satisfactory results. According to the tank test results. at a draught of 12.50m and designed ship speed of 14.50 knots, an 8.38% reduction of DIIP has been obtained with the simultaneous use of rudder-hall and wake equalizing ducts. When the draught...

... oelastic effect skewed blade procedure loading reduction displacement deflection cavitation distortion distribution geometry application rotation torque thrust THE SOCIETY OF NAVAL ARCHITECTS AND MARINE ENGINEERS 601 IPavonia Avenue, Jersey City, NJ 07306 Paper to be presenled al...

... The effectiveness of propeller polishing on the reduction in fuel consumption is reviewed from a theoretical viewpoint, and compared With a number of actual trials carried 0ut on several types and classes of ships. The data demonstrates true benefit does result from periodic polishings...

... conditions with pull or reduced power, often at constant propeller RPM, must be fulfilled. In all the cases it is desired that no harmful cavitation phenomena appear (i.e. no erosion and vibration problems and no propeller force reduction.) Investigations in the SSPA cavitation tunnel and towing tank have...

... of different kinds of aft body fins, vortex generators and nozzles and improvement of the propeller design by blade tip unloading and/or skew and also reduction of propeller diameter to increase blade tip clearance. The consequences of these modifications have in most cases also been investigated with regard...

... reduction in SHP at 20 knots is measured. All results are tabulated and discussed. A 10 percent reduction can be expected for an optimized propeller design. Noise tests have not been carried out yet, but they are proposed for future investigation. In conclusion, the work to date indicates that the concept...

... reduction thrust approximation expression amplitude midchord skew frequency variation evaluation null representation skew unsteady thrust polynomial restriction application ~' THE SOCIETY"OF NAVAL ARCHITECTS AND MARINE ENGINEERS One World Trade Center, Suite 1369, New York, N.Y. 10048...

... operating conditions. Sketches, drawings, and other data depicting the test rig are included. arrangement propeller mover naval architect ship marine transportation requirement reduction configuration completion efficiency aft propeller torque reaction world trade center suite 1369...

... methods by which a reduction of the vibration l evel s can be effected . Nevertheless , the choice is frequently reduced by t he availability of the appropr iate design data or alt e r natively the finance allocated to finding and implementing a solution. Consequently , in the majority of cases the r...

... the speed ratio of the full- size ship and the model, the RPM ratio and the ratio of the natural frequencies of the blades. The Froude number equality results in the well known reduction of mo del speed with a factor l a (a be ing the scale reduction). The time scale is e qually reduce d with a factor l...