Hydrodynamic Numerical Computation Of Hybrid Monohull

The hybrid monohull is the monohull with a build up stabilizing appendage (Semi-Submerged Body and bow fin) on the bottom of the stern. The stabilizing appendage can reduce the range of the longitudinal motion of the monohull in waves considerably and such is proved in the experiment of the real ship. Because the shape of hybrid monohull at the bow is quite complex and the viscosity force is the main component of the damping force in the drainage area of the bow when the ship moves in waves so that the result of the motion prediction by the potential flow method is very different from the experiments'. Therefore, this paper try to use the numerical compute method considering the effect of the viscosity to improve the precision of the sea keeping prediction. the paper takes one 1000 tons hybrid monohull as a object of the research and the paper will use potential method and RANS method to compute the hydrodynamic coefficients of two-dimensional stations and the three-dimensional hull. In the end, the paper use the hydrodynamic coefficients computing by the three-dimensional potential method and RANS method to predict the longitudinal motion of the ship in regular waves at speed of zero.The result of the hydrodynamic indicates that comparing to the two and three-dimensional potential methods and the two-dimensional RANS method, the three-dimensional RANS method can reflect viscid effect of the SSB and the influence of the flow around the ship in the longitudinal direction rationally. The prediction of the hybrid monohull's the longitudinal motion in regular waves at speed of zero also indicates that three-dimensional RANS method can reflect SSB's viscid influence reducing the motion of hybrid monohull in waves.