FREE-SURFACE EFFECTS IN HULL PROPELLER INTERACTION

The quantitative role of wavemaking at the free surface in the phenomenon of hull propeller interaction is investigated by means of a general scheme devised to determine the potential, viscous and wave components of wake and thrust deduction. It requires the concerted application of various analytical tools such as the lifting line theory of propellers, the method of singularities for representing the hull and propeller by source distributions and the linearized free-surface theory of wavemaking, as well as model experiment techniques such as the convention Froude analysis of propulsion factors, nominal wake measurements and wave profile measurements. The procedure is actually applied to the specific case of a thin mathematical hull form driven by a four-bladed propeller of simple geometry. It is found that the wave component is dominant in the wake and quite significant in the thrust deduction at Froude numbers around 0.3. Surprisingly, there seems to be an appreciable viscous component in the thrust deduction at practically all Froude numbers.

  • Supplemental Notes:
    • This research was carried out in part under the Naval Ship Systems Command General Hydromechanics Research Program Subproject SR-009-01-01 administered by Naval Ship Research and Development Center Contract N00014-67-A-0181-0028.
  • Corporate Authors:

    University of Michigan, Ann Arbor

    Department of Naval Architects and Marine Engineers
    Ann Arbor, MI  USA  48109
  • Authors:
    • Nowacki, H
    • Sharma, S D
  • Publication Date: 1971-9

Media Info

  • Features: References;
  • Pagination: 118 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00032189
  • Record Type: Publication
  • Source Agency: University of Michigan, Ann Arbor
  • Report/Paper Numbers: 112
  • Files: TRIS
  • Created Date: Apr 21 1972 12:00AM