The catamaran is composed of two monohulls, the flow fields between the inner and outer side of each monohull are different, the bodies must be considered as lifting bodies. So it is very important to know the lifting effect on hydrodynamic characteristics of catamaran hull at the preliminary design stage of its hull form. The pressure Kutta condition is imposed on the trailing-surface of the lifting body by determining the dipole distribution, which generates required circulation on the lifting part. The method is based on Green’s second theorem. Rankine Sources and dipoles are placed on boundary surfaces. Time-stepping scheme is adopted to simulate the wave generated by the catamaran with a uniform speed in deep water. The values of the potential and position of the free surface are updated by integrating the nonlinear Lagrangian free surface boundary conditions for every time. A moving computational window is used in the computations by truncating the fluid domain (the free surface) into a computational domain. The grid regeneration scheme is developed to determine the approximate position of the free surface for the next time step. An implicit implement of far field condition is enforced automatically at the truncation boundary of the computational window, Radiation condition is satisfied automatically. The influences on the wave making resistance of the distance between the twin hulls of the Wigley catamaran on the hydrodynamic characteristics are discussed. The numerical results are presented compared with the existing simulation result. The method can be used to simulate the flow fields around the foil near free surface.

This content is only available via PDF.
You do not currently have access to this content.