Calculation Method For High - Speed Ship Waves Increasing Resistance

Added resistance of ship in waves is one of the important research contents in seakeeping performance. Added resistance will reduce the speed and impact the operation of ship and economic benefits.2.5D theory and strip theory are common methods for studying added resistance of high-speed displacement craft. In recent years, along with the development of compute and computer technology, more and more ship designer pay attention to the advantages of using computational fluid dynamics(CFD) to predict ship hydrodynamic performance. Numerical wave tank which is based on CFD theory provide a new way for study hydrodynamic performance of ship.Firstly, using software Fluent establish tow-dimensional numerical wave tank. Physics wave-generating imitating method is adopted to simulate regular waves. In this paper I compared wave form of numerical wave tank with artificial damp zone and numerical wave tank without artificial damp zone, certificate the effectiveness of artificial damping method. Secondly, using input wave-generating method simulating regular wave, compare with numerical wave form generated by physics wave-generating imitating method, analysis feature of the two method get the conclusion that input wave-generating method is better than physics wave-generating imitating method in wave form and calculation time. Anglicizing wave form generated by input wave-generating method obtained the attenuation laws of numerical wave. The input wave-generating method and artificial damping method are applied to the three-dimensional wave tank. Through comparing and analysis wave form of tow dimensional wave, three-dimensional as well as theory wave certificate that using input wave-generating method and artificial damping method three-dimensional wave tank can obtain regular wave which meet practical requirements.Based on three-dimensional wave tank, this paper work on added resistance of high-speed displacement craft. Selects WigleyⅢ ship model, adopt dynamic mesh technology and motion control program to simulating the heave and pitch motion of ship in heading regular wave and calculating added resistance. The result is compare and analyses with the theory calculation result and experiment value, preliminary study of CFD calculation method for added resistance of high-speed displacement craft. Then, through Model5b ship model verified the applicability of this method.