COMPARISON OF WAKE DISTRIBUTIONS BETWEEN SHIP AND MODEL

Velocity distributions were measured by 5-hole pitot tubes at a section about 1.1D before the propeller on a ship and the models. The lengths of the ship and models are 167 m, 8.267 m and 4.5 m respectively. The smaller model was used for the preliminary tests to plan the full-scale measurements. The measured results are shown both for the ship and models. Principal conclusions obtained are as follows: 1. Velocity distributions in the boundary layer does not follow the 1/n law and shows a tendency to separation, at the measured section, which is more remarkable on the models than on the ship. 2. The pattern V sub x/V and the vector of V sub yz/V coincide well qualitatively between the ship and models except in the region near the hull at the shaft center line. 3. So-called stern vortex is affected by Reynolds No., and the vortex of the ship is reduced by more than the ratio of thicknesses of the boundary layers between the ship and model. 4. According to the three-dimensional expression for the flow around the stern, the flow before the propeller reaches the propeller disc, keeping the general tendency constant, including the complicated vortex flow. This fact will give a hint to obtain the better estimation for wake values of the ships. 5. The values of (2-omega s)(1-omega m) calculated by various methods are given.

• Corporate Authors:

  Society of Naval Architects of Japan

  23 Shiba-kotohiracho, Minato-ku
  Tokyo 135,   Japan 
• Authors:
  • Yokoo, K
  • TAKAHASHI, H
  • Nakato, M
  • Yamazaki, Y
  • Tanaka, H
  • Ueda, T
• Publication Date: 1973-11

Media Info

• Features: References;
• Pagination: p. 25-36
• Serial:
  • Selected Papers, J of Soc of Naval Arch of Japan
  • Volume: 11
  • Publisher: Society of Naval Architects of Japan

Subject/Index Terms

• TRT Terms: Fluid resistance; Hulls; Velocity; Wakes
• Uncontrolled Terms: Hull resistance
• Old TRIS Terms: Model testing; Velocity profiles; Wake surveys
• Subject Areas: Design; Marine Transportation;

Filing Info

• Accession Number: 00057583
• Record Type: Publication
• Source Agency: Society of Naval Architects of Japan
• Files: TRIS
• Created Date: Sep 19 1974 12:00AM