A STUDY OF FLOW PAST A SHIP-LIKE BODY,

Abstract

A method is presented for calculating the flow about ship-like bodies in the presence of a linearized free surface and also for determining the interaction effect of potential flow and boundary layer on wave-making resistance. The complete velocity potential for a vertical line source and its image system is derived and the expressions for the velocity components obtained. A computer program was written to evaluate these components and the potential at any field point. Several numerical methods for predicting the value of oscillating integrals were evolved to greatly reduce computer calculation time. To obtain a ship-like body whose wave system satisfied the linearization assumptions, many source lines with varying strengths and positions are required. This large number of source lines makes it prohibitively time consuming to calculate body streamlines. The zero Froude number condition corresponding to a planar free surface has a simple image system and the streamlines on the body are obtained directly by numerical integration. At selected points on the waterline of this body the velocities due to the complete potential are calculated from which the wave profile is determined. In the second part of the study a revised method is presented for the calculation of the three dimensional boundary layer characteristics in streamline coordinates, having the potential flow solution of the first part available. (Author)

Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1966
Accession Number
AD0649159

Entities

People

  • J. D. Lin
  • R. S. Hall Jr

Organizations

  • University of Connecticut

Tags

Communities of Interest

  • Ground and Sea Platforms

DTIC Thesaurus Topics

  • Boundaries
  • Boundary Layer
  • Computer Programs
  • Computers
  • Flow
  • Froude Number
  • Integrals
  • Layers
  • Mathematics
  • Numerical Integration
  • Potential Flow
  • Resistance
  • Three Dimensional

Fields of Study

  • Physics

Readers

  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Fluid Dynamics.