Accession Number : ADA119315

Title :   First International Conference on Numerical Ship Hydrodynamics Held in Gaithersburg, Maryland on 20-22 October 1975.


Personal Author(s) : Schot,Joanna W ; Salvesen,Nils

PDF Url : ADA119315

Report Date : Jan 1975

Pagination or Media Count : 742

Abstract : The purpose of this First International Conference was to present new results in the field of numerical ship hydrodynamics and to call attention to new computer techniques that can be used to attack problems in the areas of free surface flows, cavity flows, and viscous/boundary layer flows. Discussed are the free surface, origin of ship waves and wave resistance, and also the dominant factor in the study of the motion of ships at sea. If the free boundary condition can be applied in a linearized approximation, analytical formulae can be widely applied, such as in thin or slender ship theory. However, the limitations of the approximations readily become apparent. A second serious simplification of the theory is the absence of viscosity. The frictional component of ship resistance can only be obtained by empirical methods and extrapolation procedures. The structure of the wake behind the hull, which is of dominant importance for the prediction of propeller behaviour can only be determined by measurements, which are mostly performed at model scale. Theoretical information on this wake could follow from calculations of the turbulent boundary layer around a ship hull. A second problem, which belongs to the subject of numerical methods in ship hydrodynamics is the calculation of the pressure distribution on propellers, which is coupled to cavitation effects on the blades.

Descriptors :   *Ships, *Hydrodynamics, *Numerical methods and procedures, Symposia, International, Computerized simulation, Boundary layer flow, Viscous flow, Boundary layer, Turbulent boundary layer, Cavitation, Water waves, Wake, Mathematical models

Subject Categories : Marine Engineering
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE