The Optimum Offsets Design Of Containers Involved In Parametric Rolling And Resistance

As one of the three main types of ships in ocean transportation,container ships play an important role in the shipping industry.However,container ships are vulnerable to parameter rolling,one of stability failure modes.The second generation integrity stability criterion to be implemented in the future will have a significant impact on the design methods of container ships.Based on CAESES and SHIPFLOW,the hull shape optimization software is used to deform the hull to meet the requirement of parametric rolling stability,and then the resistance optimization of the new hull shape which meets the requirement of parameter roll stability is carried out.The main work of this paper is as follows:(1)The mechanism of Parametric Rolling in the second generation integrity stability and the calculation method of the first and second layer weakness criterion draft are described.(2)This paper expounds the principle of hull deformation,probes into the influence trend of hull profile transformation on the weakness of parameter roll,and transforms the hull surface of the forebody above the water line to obtain the hull shape which can improve the stability of parameter roll.(3)To optimize the resistance of mother ship,the influence trend of bow front end height,bow length and forebody water line on hull resistance is explored by manual enumeration and software built-in algorithm.When the bow length or forebody water line height and the shape of forebody water line are changed separately,the bow extension,forebody water line height increase and forebody water line shape become more obvious in a certain range.Full filling is beneficial to drag reduction,and when the bow and the front end height are considered comprehensively,the most advantageous scheme for drag reduction is not only the superposition of the optimal scheme with a single parameter.(4)A new hull type is obtained by series deformation of hull and parameter roll stability checking.On this basis,resistance optimization is carried out to obtain the optimal resistance surface.Finally,parameter roll stability checking is carried out again for the optimal resistance surface,and the optimal resistance hull shape line satisfying the requirement of parameter roll stability checking is obtained.