Optimization Design Of Underwater Vehicle Profile Based On Multidisciplinary Optimization Design

In the process of underwater vehicles design,one of important contents is profile design,and it has an extremely important influence on the resistance and energy consumption of the underwater vehicle when navigating in the water.Traditionally,people use the method of serial single-disciplinary design for the underwater vehicle profile design,which is designed one by one for each performance(discipline)of the underwater vehicle.This method separates the coupling relationship between various disciplines artificially,ignores the interaction between various disciplines,and easily leads to the loss of the overall optimal value in the optimization process.Moreover,this method is time consuming and costly.This paper explores and studies the application of multidisciplinary design optimization in the optimization design of underwater vehicle profiles.The main contents include:(1)Introducing the research background and significance of the project:illustrating the research progress and the latest achievements in the design optimization of underwater vehicle profile at home and abroad.Combined with the characteristics of underwater vehicle design process,it illustrates the limitations of traditional methods in design optimization,also,the feasibility and necessity of applying multidisciplinary design optimization to underwater vehicle design optimization are introduced.(2)Introducing the basic principle,the modeling methods and steps of one of the methods of multidisciplinary design optimization—the method of generalized collaborative optimization;proposing improved measures for the defects of the consistency constraint in the standard collaborative optimization method,and proposing a combinatorial optimization strategy.The adaptive simulated annealing algorithm is combined with the modified feasible direction method.The adaptive simulated annealing algorithm is used to ensure the global optimal solution.The modified feasible direction method is used to ensure the fast convergence of the algorithm.The gear reducer optimization problem and a second-order coupling example was used to prove the validity of proposed combination optimization strategy.(3)The three-dimensional model——SUBOFF of the underwater vehicle was constructed by the soft ware of Creo,and the direct numerical simulation was carried out in the module of fluent in ANSYS.The computational fluid dynamics(CFD)technique was used to construct the numerical simulation pool test.From the comparison of numerical simulation results with experimental data,the validity of the numerical simulation pool,the selected meshing method and the numerical calculation method constructed in this paper can be verified.(4)Using the way of Design of Experiments(DOE),adopting the full factor test method to select sample points and the radial basis neural network model was used as the construction method of the approximate model,then the approximate model constructed in this paper was saved to the library in Isight.So the approximation model can be called directly when the optimization application is performed.The introduction of the approximate model makes the design system simple and efficient,and can not only meet the requirements of engineering precision,but solve the contradiction between efficiency and precision in the process of underwater vehicle profile design.(5)Using Isight as an optimization platform,a generalized collaborative optimization framework for two sub-disciplines(resistance and energy consumption)of underwater vehicles was established.The three-dimensional modeling,meshing and numerical simulation of underwater vehicles are integrated to form an integrated platform of automatic design-analysis-calculation-optimization.The optimization results of the underwater vehicle profile are compared with the original profile.