Study On The General Design And Hull Form Optimization Of The LNG Carrier

LNG carrier is the high-valued civil ship, China shipbuilding industry is now exploring to research and design LNG carrier. In this thesis, the evolution and development foreground of the LNG carrier are systematically analyzed. According to the real ship document, using regression method to analyze the principle dimensions of the LNG carrier. General arrangement , typically structural gas cargo tank and special fireproofing requirement of the LNG carrier are analyzed in detail.The resistance of the LNG carrier is divided into three areas: in the first potential flow area, calculate the liquid velocity potential in the way of Second steps panel method based as Dawson method, as Rankine sourse, satisfied with free surface boundary condition through iteration method; in the second thin boundary layer area, compute the middle and the fore part of the ship boundary layer as boundary layer method, from the stagnation point using the integral method to laminar flow and then the transition; in the third turbulence area, the calculation of the viscous resistance is used Renault Average Navier-Stokes (RANS)Equation as two equations k - e turbulence model in the following ship coordinate system and its boundary condition depends on the results calculated by the boundary layer and potential flow, using finite analyze method or SIMPLE method to treat the coupling between velocity and pressure.The molded line optimization method which is based on the resistance performance , using upright design method to optimize the bulb bow of the father LNG carrier to get nine different schemes, and calculate their wave resistance, friction resistance and viscous resistance. After comparison, it can be got the optimization ship type.