Turbulence at the Stern of an Axisymmetric Model with and without Removable Appendages

Abstract

The time-varying flow features of an axisymmetric model with removable appendages are studied. The random turbulence structure of the axial velocity component at an assumed propeller plane, but in the absence of a propeller, is examined through statistical techniques. Data are provided on the ingested turbulence for a three-dimensional axisymmetric geometry. The axial mean and axial fluctuating velocities are presented over the entire boundary layer region of the assumed propeller plane. The autocorrelation and power spectral density functions are presented at three radii and ten circumferential angles. The circumferential means of the axial integral length scales obtained from this model have been found to range from 10% to 15% of the maximum hull radius. In the absence of appendages, the largest values of this length scale occur near the hull boundary. In the presence of the appendages, the largest length scale occurs at the middle radius. At the outermost radius, roughly the maximum propeller radius, the integral length scale took on its smallest value. This value remained constant for all appendage configurations.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1992
Accession Number
ADA246217

Entities

People

  • Chen-wen Jiang
  • Nancy C. Groves
  • Yuan-ning Liu

Tags

Communities of Interest

  • Energy and Power Technologies
  • Ground and Sea Platforms
  • Sensors

DTIC Thesaurus Topics

  • Autocorrelation
  • Axisymmetric
  • Boundaries
  • Boundary Layer
  • Classification
  • Computational Fluid Dynamics
  • Databases
  • Digestive System Processes
  • Fluid Dynamics
  • Integrals
  • Layers
  • Measurement
  • Physics Laboratories
  • Propellers
  • Reynolds Number
  • Statistical Analysis
  • Turbulence

Fields of Study

  • Physics

Readers

  • Fluid Dynamics.
  • Marine Hydrodynamics