A Contribution to Flow-Separation Problem in Unsteady Motion of a Body.

Abstract

Roll motion is the least predictable of ship motions, largely because of viscosity effects, which in turn causes flow separations to occur. As a result of these phenomena, roll damping is often highly nonlinear. It is best estimated in the present state of the art by strictly empirical methods. In this report, several relevant flow-separation problems are studied from a fundamental point of view. These are divided generally into two categories: (1) boundary-layer separation and (2) sharp-edge separation. In both cases, starting motion and oscillatory motion are considered separately. Emphasis is placed on rather simple methods of calculations. Results are compared with experiments and/or more detailed calculation methods wherever such are available. Finally, a procedure is proposed (but not carried out) for treating the formation of vortex sheets by a translating rolling ship hull. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1979
Accession Number
ADA086294

Entities

People

  • Yoji Himeno

Organizations

  • University of Michigan

Tags

Communities of Interest

  • Air Platforms
  • Weapons Technologies

DTIC Thesaurus Topics

  • Boundary Layer
  • Engineering
  • Engineers
  • Flow
  • Flow Fields
  • Flow Separation
  • Hulls (Marine)
  • Hydrodynamics
  • Layers
  • Marine Engineering
  • Mechanical Properties
  • Mechanics
  • Naval Architecture
  • Physics Laboratories
  • Pressure Gradients
  • Ship Hulls
  • Shipbuilding

Readers

  • Aerodynamics/Aeronautics.
  • Fluid Mechanics and Fluid Dynamics.
  • Theoretical Analysis.