The effects of the dimensions, the shape and the speed of the ship on the pressure distributions in surrounding sea water

Abstract

Presented in this paper are numerical method used to study of viscous flow around a ship hull, numerical simulations and obtained results, to establish the effects of dimensional and movement parameters of the ship on the pressure distributions in surrounding sea water. In this numerical scheme, the three-dimensional viscous flow around an advancing ship is computed by the finite-difference method, the viscous flow is simulated for ships of a displacement type and the free surface effects are neglected. The governing equations are the Navier-Stokes equations and the continuity equation for the three-dimensional incompressible fluid. The body-fitted curvilinear coordinates system is introduced to cope with the body boundary of an arbitrary form. Assuming symmetricity of a flow field, only the half side of the center plane is solved. The computational region in the physical space is transformed into the parallelepiped in the computational space. The body boundary is usually transformed onto a plane in the computational space, which enables the simple treatment of boundary conditions. Viscous flows around a variant hull of the Wigley model are computed by the present scheme. In order to investigate the influences of dimensional and movement parameters of the ship on pressure distributions in sea water, the following parameters were varied systematically: the model speed, the main dimensions of the model, and the displacement, respectively, the model length, the value of the block coefficient, the value of the longitudinal prismatic coefficient and the value of the ratio of breadth to depth.