Optimization Of Submarine Resistance And Maneuverability Based On SBD Technology

In the traditional design pattern,the designers simulate,summarize and select multiple schemes based on empirical attempts for the deepening and design of existing schemes,which is time-consuming and laborious,and cannot guarantee better results.In order to solve the backward design bottleneck in the traditional design concept,this paper uses SBD technology to carry out geometric reconstruction,experimental design,numerical simulation,surrogate model establishment and multi-objective optimization of surface and underwater resistance,and analyzes each step in the process in detail.Aiming at the geometric reconstruction of Suboff with full appendage submarine model,considering that the submarine needs to inherit the shape and performance of the mother ship in the optimization design process,this paper adopts and compiles the Lackenby parametric geometric reconstruction method,and Lackenby method was improved,which makes the geometric reconstruction obtain more practical design variables.In addition,considering the requirement that the longitudinal center of buoyancy above and below water are approximately equal in the submarine design process,which is very difficult to achieve in the traditional design,the constraint conditions for the longitudinal center of buoyancy are added in the geometric reconstruction and the following multi-objective optimization.In order to solve the need to calculate the fitness value of particles evolved in each iteration in the optimization process,this paper compiles and uses the Optimized Latin Hypercube Sampling(OLHS)experimental design method to design the design space of multi-dimensional schemes,and obtains several representative feasible optimization schemes,which lays a foundation for the following surrogate model establishment and resistance multi-objective optimization.In order to obtain the resistance and tactical turning diameter of each reconstruction scheme as accurately as possible,this paper uses CFD method to simulate all reconstruction models,including RANS method for underwater state with SST k-ω physical model,RANS method for water surface state with k-epsilon turbulence model.The numerical calculation is verified according to the experimental result of Suboff full appendage model in American David Taylor model basin and DTMB 5415 experimental data published by INSEAN,and the grid independence verification is studied in detail to ensure that the numerical simulation results are in line with objective facts.The initial sample values are obtained by experimental design and numerical simulation are analyzed by approximate technology,and the design variables and fitness values in the whole design space are simulated by Kriging model,which frees the dependence on numerical simulation in the iterative process of resistance optimization.In addition,the coupling effect images of different variables on fitness values are obtained,which has important reference value for optimization design.In this paper,the multi-objective constrained particle swarm optimization(MOCPSO)algorithm is compiled,and the relative parameters are optimized in detail,which is verified by the test function,and used for the multiobjective optimization of resistance and maneuverability to obtain Pareto optimization solution set.According to certain criteria,three candidate optimization schemes are selected,their applicable scenarios are analyzed,and the resistance,maneuverability and longitudinal position of floating center above and below water are verified to ensure the accuracy and feasibility of optimization.