CONSTANT THRUST VERSUS CONSTANT VELOCITY METHOD FOR RESISTANCE MEASUREMENT IN WAVES

Constant thrust and constant velocity methods of towing for the resistance measurement of ship models in waves were compared in irregular waves of four different spectral content. The results indicate that there is no difference in results between the two methods. This is very encouraging, because the constant velocity towing is very much easier to perform, and the results are more reliable and accurate. A new constant velocity dynamometer was designed and built so that the periodic forces, caused by orbital velocities in waves, and the net horizontal force can be separated. This is done by integration. The average slope of the integrated dynamometer output curve represents the net horizontal force. (Author)

• Supplemental Notes:
  • Patent filed 23 February 1971.
• Corporate Authors:

  University of California, Berkeley

  College of Engineering
  Berkeley, CA  United States  94720
• Authors:
  • Sibul, O J
• Publication Date: 1971-6

Media Info

• Pagination: 36 p.

Subject/Index Terms

• TRT Terms: Fluid resistance; Hulls; Tests; Towing devices; Wave resistance; Waves
• Uncontrolled Terms: Hull resistance
• Old TRIS Terms: Irregular waves; Model testing; Towing tests
• Subject Areas: Design; Marine Transportation;

Filing Info

• Accession Number: 00025659
• Record Type: Publication
• Source Agency: National Technical Information Service
• Report/Paper Numbers: NA-71-1
• Contract Numbers: N00014-69-A-02001014
• Files: TRIS
• Created Date: Feb 11 1972 12:00AM