SOME PRACTICAL CONSIDERATIONS IN REDUCING REQUIRED POWER FOR SHIPS

Various methods of reducing the propulsive power required by screw-propelled ships are considered. These include reducing surface roughness of hull and propeller, selecting optimum hull proportions and fullness for reduced power operation, enlarging the diameter of the propeller together with reducing propeller RPM, use of a ducted propeller rather than an open propeller, possible use of contra-rotating propellers, alternative modes of operation of twin screws at reduced power, reduction of above-water hull and superstructure resistance due to air drag are discussed in this report.

• Corporate Authors:

  National Maritime Research Center, Kings Point

  United States Merchant Marine Academy
  Kings Point, NY  United States  11024

  Webb Institute of Naval Architecture

  Glen Cove, NY  United States 
• Authors:
  • Hamlin, N
• Publication Date: 1977-10

Media Info

• Pagination: 61 p.

Subject/Index Terms

• TRT Terms: Aerodynamic force; Contrarotating propellers; Drag; Ducted propellers; Energy consumption; Fluid resistance; Hulls; Merchant vessels; Propellers; Propulsion; Roughness; Ships; Shrouded propellers
• Uncontrolled Terms: Hull resistance; Merchant ships; Ship hulls
• Old TRIS Terms: Drag reduction; Marine surface propulsion; Power prediction; Power requirement; Twin screws
• Subject Areas: Design; Energy; Marine Transportation; Vehicles and Equipment;

Filing Info

• Accession Number: 00175136
• Record Type: Publication
• Source Agency: National Technical Information Service
• Report/Paper Numbers: NMRC-KP-161
• Files: TRIS
• Created Date: Apr 26 1978 12:00AM