| Bracket is the common structure used as the connect component in submarine. Itcan effectively increase the continuity of the structure and reduce the stress concentrationof the junction. The stress can be concentrated at the toe of bracket because of complexload and large stress variety of the bracket and large stiffness variety at the joint whichmakes the bracket destroyed easily at the toe. It is significant to carry out a strengthanalysis and optimization design of the bracket.In this thesis, the internal plane bulkhead and pressure shell structure are analyzed byfinite element method with APDL which lays a foundation for the subsequent optimizationwork. The internal plane bulkhead bracket structure is studied and a topology optimizationto the rectangular bracket structure is developed. A new type of outer curved bracketstructure is obtained. The force analysis of the outer curved bracket is developed by usingthe finite element software ANSYS, the result of which is compared with the triangle andinner curved bracket. The advantages and disadvantages about the stress concentration andstructure weight of the above three bracket are discussed. The results show that the curvedbracket has lower stress concentration than the triangular bracket. It has certain guidingsignificance to determine the shape of the bracket preliminarily by using the topologyoptimization method in ANSYS.An outer curved bracket and an inner curved bracket with smaller stressconcentration are studied. A mathematical model of the bracket optimization is created bytaking the structural dimensions as design variables, the stress as constraints, the structuralweight as objective function, which is solved by the genetic algorithm. The parametersneeded to calculate the fitness are obtained by calling ANSYS in the procedure of thegenetic algorithm. At last the better dimensions of the two types of brackets are obtained.The optimization results show that the weights of the two optimized brackets aredecreased than the initial program. The proposed optimization method for the actual design of the bracket structure has a certain reference value. |
