Study On Resistance Performance Of "YUPENG" Vessel Based On CFD Theory

In 2019,in order to promote comprehensively the construction of a transportation power,China put forward the " Outline of building a powerful transportation country ",which clearly pointed out: to promote the upgrading of equipment and technology,transportation equipment should be advanced and applicable,and at the same time,it needs green development,conservation and intensive,low-carbon and environmental protection.Marine transportation accounts for 80% of the total global trade.In order to improve the efficiency of ship transportation and protect the marine environment,the research on ship rapidity is very important.Ship resistance is an important factor affecting rapidity,and it is also an important basis for ship form design and optimization.The research methods of ship resistance performance mainly include model test,theoretical research and numerical simulation.Model test method is the most mature method at present,but it has some defects such as high cost,limited flow field information,measurement accuracy and scale effect.The theoretical research method needs a lot of relevant data and is limited to ships with simple geometry.With the development of computer technology,computational fluid dynamics(CFD)method is developing rapidly.Compared with traditional methods,it is more economical,efficient and flexible,and has become an important research method in the field of ship hydrodynamic.Taking “YUPENG” vessel as an example,this thesis calculates and analyzes the ship resistance performance by CFD method.Firstly,Solid Works software is used to build a three-dimensional hull model.Based on STAR-CCM+,the ship resistance of “YUPENG” model at six speeds in static water is calculated.The total resistance,friction resistance and other results are compared with the model test and empirical formula to verify the rationality of the establishment of the model,the selection of calculation area,mesh division and physical parameter setting.Secondly,the resistance performance of “YUPENG” vessel at different speeds and three draft is calculated,and the relationship between draft and resistance is analyzed.Then,under the condition of keeping the ship at full draft,the resistance of different speed and trim angle is calculated.It is found that the resistance can be changed by adjusting the trim angle.When the ship is sailing with a certain angle of trim,the resistance can be reduced,which plays the role of energy saving and emission reduction.The numerical wave tank is created,simulated the head wave motion of “YUPENG” vessel in regular waves with different wavelengths is using overset mesh technology.The ship motion response and wave added resistance are calculated with the calculation results of static water resistance,the relationship between ship pitch and heave with wavelength is studied.The semi empirical formula is used to calculate the total wave added resistance,radiation component and diffraction component,when Fr = 0.15 and Fr = 0.2,the influence of speed and wavelength on the ship resistance performance is analyzed.The results show that the diffraction component accounts for the majority when the wavelength is short,while the radiation component is the main component when the wavelength is medium or long.Compared with the CFD results,the variation of wave added resistance coefficient is consistent.The method proposed in this thesis can effectively predict the sailing resistance of ships,broaden the understanding of the resistance mechanism,and provide certain guidance for ship design,ship loading and ship operation.