BLADE FREQUENCY HARMONIC CONTENT OF THE POTENTIAL WAKE OF SINGLE SCREW SHIPS,

Abstract

Using thin ship theory, approximate formulas are developed for the axial velocity at the propeller plane. Harmonic analysis of the flow variation at one radius is carried out to provide the harmonic content at the propeller plane of U- and V-sectioned hull forms and a strut of infinite draft for which the exact solution is known. These results are compared with the harmonic content obtained from experimental model data. The potential wake harmonics are compared with those obtained from model tests and are found to be much smaller. An estimate is made of the harmonic content of the viscous wake. Vibratory thrust computations for a specific propeller, using the wake velocities of the U- and V-sectioned hull forms, are included. It is concluded that the potential flow contribution to the harmonic content of the flow at the propeller plane and the resultant vibratory thrust is of an order of magnitude smaller than that which arises from viscous effects. (Author)

Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1963
Accession Number
AD0427833

Entities

People

  • C. L. Odenbrett
  • J. P. Breslin

Organizations

  • Stevens Institute of Technology

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Computations
  • Flow
  • Frequency
  • Harmonic Analysis
  • Harmonics
  • Hulls (Marine)
  • Mathematics
  • Model Tests
  • Potential Flow
  • Propellers

Fields of Study

  • Physics

Readers

  • Aerodynamics.
  • Calculus or Mathematical Analysis