Accession Number : ADP003048

Title :   A Computation of Flow around a Ship,


Personal Author(s) : Hershey,A. V.

Report Date : 17 NOV 1983

Pagination or Media Count : 5

Abstract : A computation system is under development for the determination of velocity in the wave trains of submarines and ships. The first order linear approximation is used for the free boundary, while full accuracy is used for the body boundary. The body shape is simulated geometrically by a radical representation, and is simulated hydrodynamically by continuous distributions of source density. A point source is centered in a parallelepiped, which is large enough to bracket the ship. Velocities at grid points in the parallelepiped have been computed by Fourier integration, and have been converted into coefficients for interpolation by the fast Fourier transform. The velocity at each point on the surface of the ship is computed for unit source density at each other point. Then a matrix of flux is inverted to obtain the source density. The square of the velocity is integrated in accordance with the Bernoulli equation to obtain the wave resistance. (Author)

Descriptors :   *Water waves, Ship hulls, Water flow, Resistance, Subroutines, Computations, Coefficients, Surface waves, Velocity, Wake, Pressure distribution, Fast fourier transforms, Nonlinear differential equations

Distribution Statement : APPROVED FOR PUBLIC RELEASE