Hull Design And Resistance Performance Study Of Trimaran Small Waterplane Area Center Hull

The proposal of trimaran is a milestone event in the 21 st century.Trimaran has wider deck area and better stability,resistance and Seakeeping performance.On the basis of inheriting the excellent performance of the conventional slender trimaran,the Trimaran Small Waterplane Area Center Hull improves the ship performance.Therefore,it has broad application prospects in both civil and military fields.In this paper,a rapid automatic generation system for trimaran hull is developed independently,in which the hull model suitable for simulation test can be obtained by fast transformation of hull scheme.Through the study of hydrostatic resistance performance,the influence of grid uncertainty on the calculation results under simulation conditions is analyzed,and then the optimal mesh scheme for trimaran could be generated.By comparing and analyzing the resistance performance of different side-hull configuration,the variation of resistance of trimaran in different speed and the proportion of resistance component different from that of mono-hull ship are received.The details are as follows:(1)The basic theory,numerical simulation method,turbulence model selection,meshing selection,initial and boundary conditions of viscous flow field of ship are introduced in detail,which provides theoretical support for the subsequent research on resistance.(2)Programming and developing the automatic generation system of hull lines for conventional slender trimaran and TRISWACH.Firstly,the principle and modeling method based on AutoCAD are introduced briefly.Secondly,the design flow chart of trimaran is presented.Finally,the design of wigley trimaran mathematical ship and TRISWACH profile are carried out in detail.(3)Side-hull configuration and sensitivity analysis of watershed affecting factors are conducted.Firstly,the configuration design of the TRISWACH in the numerical simulation test is presented,and the simulation scheme is introduced in detail.Secondly,the influence of different mesh size,the first layer mesh thickness and the mesh size of the densified area on the numerical results of conventional slender trimaran is analyzed,and more accurate hull mesh generation scheme is obtained.(4)The hydrostatic resistance of conventional slender trimaran and TRISWACH in different speed and different side-hull layout schemes is calculated.By comparing the total resistance with the residual resistance,and the wave-making clouds,the change of the resistance,the change steady of resistance can be obtained and that is different form mono-hull's.