The Structure Optimization Design Basic On Improved Genetic Algorithm For Carriers Of River-sea Direct

As a component of great importance in ship designing, structural design is aimed to offer the ship hull the best technical performance while guaranteeing it with necessary margin of safety on strength. The structural optimization design of a ship is based on its regular structural design. Its purpose is to take the full advantage of the structure and lower the construction cost. In short, spend less, get more. The midship is the most important section of the hull structure. It has always been a significant project that to explore a method to design midship section rationally and to seek the optimized dimension of structure elements efficiently.It has been proved that the Genetic Algorithm is an intelligent optimization method, especially effective in solving complex global optimization problems. In accordance to the structural features of the River-to-Sea bulk carrier, Improved Genetic Algorithm (IGA) is applied to the midship section optimization problem in this dissertation. Meanwhile the Guidance Notes for Survey of River-to-Sea ship and Guidelines for Structure of Double Side Skin Bulk Carriers is taken into account. The1stOpt optimization software was employed in taking advantage of IGA to program a solution on an existing case. The result of the calculation shows that the IGA turns out to be capable in global searching and quick computing. It is convinced that IGA is adept to hull structural optimization and that better optimization results could be expected. A FEM model was created and calculated via NASTRAN the CAM software in the latter part of this dissertation, aiming to certify the optimized hull structure.In addition, the author writes two programs. One of them is a structure calculation program based on CCS rules. The other is a program on longitudinal strength certification with Matlab software. With these two programs at hand, the designer can consult the dimension of structural elements in accordance with the CCS rules conveniently and obtain the reliable optimization results to complete the longitudinal bending strength certification.