Deep-sea Pressure Hull Robustness Optimization

The ocean is an important strategic space and resources treasure,therefore,as the land resources increasingly depleted,humans focused on the ocean.Development and utilization of marine rely on a variety of marine equipment,and the Manned submersible is one of the important categories.Manned submersible has the characteristics including complicated system,a great number of instruments and equipment.Among them,the pressure structure provides layout and the protection of space for a large number of instruments and equipment,and it occupies a big proportion of the total weight.Due to pressure structures in deep water need under enormous water pressure,how to ensure that it is not damaged in deep water has been the key and difficult point for submersible research.Above all,the key systems of DSV pressure structure have important influence on the safety of the vehicle,the overall performance,etc.Based on the research object of multi-hole cylindrical pressure structure,this paper mainly carries out research work as following:First,this paper analyzes the pressure structure design principles,determines the pressure structure such as the material,structure form,etc.,and use specification and the finite element analysis conducts a preliminary design of pressure structure with no hole.Then it completes the hole and strengthen design of pressure structure,and analyzes strength and stability based on the finite element analysis method of multi-hole cylindrical pressure structure.In this way,preliminary design scheme of multi-hole cylindrical pressure structure is finished.Second,the paper designs the parametric analysis process of multi-hole pressure structure,and it studies the sampling methods of sample points in the process of parametric analysiss.To solve those problems occur in the process of parameter analysis,including model building,the material property load and boundary conditions settng,meshing,carrying on the secondary development of Abaqus software based on the Python language.Parametric analysis of multi-hole pressure structure is performed,and in order to achieve the purpose of dimension reduction and reduce the difficulty of the problem analysis,sensitivity analysis of design variables is also carried out.Third,on the basis of the approximate model is introduced,the paper fits the sample points of experimental design and acquires the approximate model which fitting accuracy can meet the needs of engineering.Further it establishes deterministic multi-objective optimization model of multi-hole pressure structure,then it uses the multi-objective optimization algorithm for the solution of the optimization to get the deterministic optimal Pareto solution set of multi-hole pressure structure.And minimum distance method is used to determine the optimized scheme,which compared with the initial design.Finally,on the basis of studying robustness optimization and analyzing the rule of the robustness optimization analysis,uncertainty factors of multi-hole pressure structure robustness optimization are determined.Then it respectively study and soluted lightweight multi-objective and multi-response multi-objective robustness optimization,the optimization outcomes that content different levels,different optimization algorithm are compared and analyzed.These related conclusions can provide a reference for multi-hole pressure structure.