| Chinese shipbuilding industry has grown at overwhelming pace to dominate the top global ranks till the year of2010. However, compared with the developed countries, Chinese shipbuilding industry still has a long way to go in improving shipbuilding science and core competitiveness.Therefore, the state council issued regulations on speeding up structural adjustment and promoting the transformation and upgrading of shipbuilding industries from2013to2015. The regulations indicate that it is very urgent to tackle key technology of ship and marine engineering and improve the scientific and technological innovation. Enhancing of the core competiveness will make Chinese shipbuilding industry stronger. Ship computational fluid dynamics technology is high-tech industries on application of ship and ocean engineering using CFD. In recent ten years, with the rapid development concerning high speed and large capacity of computer and numerical simulation. It is possible to solve ship maneuverability through CFD. The new method is different with traditional method which depends on experimental tank to estimate ship hydrodynamic performance. The numerical tank will be used to study the ship maneuver motion together with the physical experimental tank.The main work of the paper lies in:(1) Numerical wave tank is established to perform the research in the field of ship maneuverability. The wave-generation methods of physical making-wave and pure numerical making-wave are employed to generate the numerical wave in the numerical wave tank respectively. The method of wave damping absorber is used to absorb the numerical wave in the numerical wave tank. The regular wave attenuation is analyzed on the aspect of mesh size, time step and discretization scheme.(2) Hydrodynamic numerical research is made on the important equipments of ship maneuver, such as rudder and propeller. The numerical computation of lift coefficient and drag coefficient for3D rudder is performed at different aspect ratio and thickness ratio and Reynolds number. The numerical results are compared with experimental results, and a good agreement is demonstrated. The pressure and velocity fields are obtained under different rudder angles. At the same time, the separation phenomenon of the viscous flow around rudder is observed and analyzed. Take four blades propeller KP458as the subject of propeller research, the propeller thrust coefficients and torque coefficients is gained in different advance coefficients, and the curve of propeller hydrodynamic performance is drew.(3) Hydrodynamic numerical research on ship direct motion and oblique motion is carried out. Viscous flow around DTMB514ship model with free surface is calculated, and the numerical results are compared with experimental results. The two methods are introduced to simulate the KCS model. The free surface is considered for the first method. The second method ignores the free surface, in other words, a mirror image which replaces the free surface is applied. The results with different methods are compared with experimental results respectively. Viscous flow around KCS model in different velocities is simulated, the force and moment are gained, and the hydrodynamic derivatives are calculated with the least-squares method. The motor vessel "YUKUN" which is the training vessel of Dalian Maritime University also is taken as the object to simulate the ship direct motion, and the hydrodynamic derivatives are calculated. KVLCC2M which is one of the standard ship form used in the comparative research is taken as the main object, and the numerical simulation of viscous flow around KVLCC2M ship model in oblique motion is carried out. The lateral force coefficients and yaw moment coefficients under different drift angles are calculated, and the hydrodynamic derivatives are gained. These hydrodynamic numerical results will be considered to use in marine simulator in the future, and it will be a good way for ship CFD practical research. |
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