Research On Optimum Design Of Container Ship Structures

As the development of global trade in recent years,container ships play an important role in the network of transportation. In order to leave more room to place more containers,modern big container ships not only have the structure of big hatch in the deck and hatch boarding,but also make special design on the bow and stern,which need particular requirements on the intensity of the hull.Based on CCS rules,the paper established the optimal model of Midship section of container ships with bending-torsional strength and frequency constraints based on CCS rules and thin-walled beam theory.According to CCS rules,the strength,stability and dimension constraints were considered in the model;according to the the thin-walled beam theory,the container ship's shear stress caused by cargo's torsion moment were considered;in terms of the vibration of the hull girder theory, the frequency constraint was considered.Based on the mathematical model, the paper integrated executable program in the ISIGHT environment; established optimal design system using adaptive simulated annealing arithmetic which can solve mixed variables optimum problems in ISIGHT environment.Optimization results of examples of 3100TEU container ship show that the area of the middle section decreases by 9.67%.After optimization of the midship section structure, the paper studied optimum design of container ship transverse bulkhead structure based on CCS rules.The high-efficiency optimization system was established.Optimization results of optimization of the 3100 TEU container ship show that the weight of transverse bulkhead decreases by 2.52%.The paper established a new system for optimization of container ship based on direct calculation method.By using PCL of PATRAN, Finite element Method (FEM) model of a general half-one-half cargo tank was estabilished.The optimum design sysytem which integrated NASTRAN and ISIGHT was estabilished on base of the FEM model. Optimization results of optimization of 3100TEU container ship show that the weight of the tank decreased by 17.44%.The paper did primary study on topological optimization and size optimization of container ship structures, which provided references for concept design of container ship's cargo tank.