A New Propulsion System has been developed to a stage of successful laboratory tests on a 10 horsepower unit. The main advantage of the new system is the substitution of a fluid transmission and engine revolution reduction by means of a fluid coupling for the standard direct drive and reduction gears. This study explored the feasibility of the application of the New Propulsion system to surface ships and in particular the advantages and the ease with which the new system can drive contra-rotating propellers. The report describes the pump driven by the prime mover supplying pressurized water to drive a hydraulic turbine located inside the hub of the propeller. For contrarotating arrangement the hydraulic turbine is split into two parts, with the blades of the after part set at opposite pitch, driving two propellers in opposite directions. The study indicates that substantial weight and cost savings are achieved by the elimination of the multi stage mechanical reduction gears and substitution of shorter and smaller diameter high revolutions shafts for the present low revolution, long and large diameter shafts. In the contra-rotating propeller case the New Propulsion System eliminates also the need for the concentric shafts with their complications of seals, bearings and reduction gear problems. Recommendation is made to test a model of the New Propulsion System of about 240 horsepower size in an existing model of 30 feet length.
Application of New Propulsion System to Contra-Rotating Propellers for U.S. Merchant Vessels
1981
89 pages
Report
No indication
English
Systematic studies of contra-rotating propellers for merchant ships
Tema Archive | 1973
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Tema Archive | 1988
TIBKAT | 1956
|Tema Archive | 1988
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