This paper proposed a reliability design model for composite materials under the mixture of random and interval variables. Together with the inverse reliability analysis technique, the sequential single-loop optimizat...This paper proposed a reliability design model for composite materials under the mixture of random and interval variables. Together with the inverse reliability analysis technique, the sequential single-loop optimization method is applied to the reliability-based design of composites. In the sequential single-loop optimization, the optimization and the reliability analysis are decoupled to improve the computational efficiency. As shown in examples, the minimum weight problems under the constraint of structural reliability are solved for laminated composites. The Particle Swarm Optimization （PSO） algorithm is utilized to search for the optimal solutions. The design results indicate that, under the mixture of random and interval variables, the method that combines the sequential single-loop optimization and the PSO algorithm can deal effectively with the reliability-based design of composites.展开更多
A new reliability-based multidisciplinary design optimization （RBMDO） framework is proposed by combining the single-loop-based reliability analysis （SLBRA） method with multidisciplinary feasible （MDF） method. Th...A new reliability-based multidisciplinary design optimization （RBMDO） framework is proposed by combining the single-loop-based reliability analysis （SLBRA） method with multidisciplinary feasible （MDF） method. The Kriging approximate model with updating is introduced to reduce the computational cost of MDF caused by the complex structure. The computational efficiency is remarkably improved as the lack of iterative process during reliability analysis. Special attention is paid to a turbine blade design optimization by adopting the proposed method. Results show that the method is much more efficient than the commonly used double-loop based RBMDO method. It is feasible and efficient to apply the method to the engineering design.展开更多
Weld bead morphology plays an important role in welding procedure specification and welding process planning.In order to obtain the quantitative relationship between process parameters and weld morphology of DH36 mari...Weld bead morphology plays an important role in welding procedure specification and welding process planning.In order to obtain the quantitative relationship between process parameters and weld morphology of DH36 marine steel plate,grey correlation method was used to study multiple morphology characteristics simultaneously.Eighteen experimental runs were proposed according to orthogonal method.With grey correlation theory,three response objectives,aspect ratio,depth of penetration and weld were transformed into a single grey correlation grade(GRG).The process parameters were quantitatively correlated to the GRG value and optimized with the target of maximum aspect ratio,minimum depth of penetration and maximum weld area.The results show that the optimized weld bead morphology is better than other weld bead morphology.The relative error of the predicted GRG with respect to the actual value is 5.06%,which further verifies the accuracy of the established model.The microstructure and hardness analysis suggests that the optimized welded joint has obtained required mechanical properties.The research outcomes provide a theoretical basis for multi-objective optimization of arc welding morphology in practical applications.展开更多
基金the National Natural Science Foundation of China(No.10772070)Ph.D Programs Foundation of Ministry of Education of China(No.20070487064).
文摘This paper proposed a reliability design model for composite materials under the mixture of random and interval variables. Together with the inverse reliability analysis technique, the sequential single-loop optimization method is applied to the reliability-based design of composites. In the sequential single-loop optimization, the optimization and the reliability analysis are decoupled to improve the computational efficiency. As shown in examples, the minimum weight problems under the constraint of structural reliability are solved for laminated composites. The Particle Swarm Optimization （PSO） algorithm is utilized to search for the optimal solutions. The design results indicate that, under the mixture of random and interval variables, the method that combines the sequential single-loop optimization and the PSO algorithm can deal effectively with the reliability-based design of composites.
基金Supported by the National High Technology Research and Development Program of China("863" Program) (2009AA04Z418, 2007AA04Z404)the National "111" Project(B07050)~~
文摘A new reliability-based multidisciplinary design optimization （RBMDO） framework is proposed by combining the single-loop-based reliability analysis （SLBRA） method with multidisciplinary feasible （MDF） method. The Kriging approximate model with updating is introduced to reduce the computational cost of MDF caused by the complex structure. The computational efficiency is remarkably improved as the lack of iterative process during reliability analysis. Special attention is paid to a turbine blade design optimization by adopting the proposed method. Results show that the method is much more efficient than the commonly used double-loop based RBMDO method. It is feasible and efficient to apply the method to the engineering design.
基金Natural Science Foundation of Fujian Province(Grant No.2020J01873)Technology Major Project of Fujian Province(Grant No.2020H03018).
文摘Weld bead morphology plays an important role in welding procedure specification and welding process planning.In order to obtain the quantitative relationship between process parameters and weld morphology of DH36 marine steel plate,grey correlation method was used to study multiple morphology characteristics simultaneously.Eighteen experimental runs were proposed according to orthogonal method.With grey correlation theory,three response objectives,aspect ratio,depth of penetration and weld were transformed into a single grey correlation grade(GRG).The process parameters were quantitatively correlated to the GRG value and optimized with the target of maximum aspect ratio,minimum depth of penetration and maximum weld area.The results show that the optimized weld bead morphology is better than other weld bead morphology.The relative error of the predicted GRG with respect to the actual value is 5.06%,which further verifies the accuracy of the established model.The microstructure and hardness analysis suggests that the optimized welded joint has obtained required mechanical properties.The research outcomes provide a theoretical basis for multi-objective optimization of arc welding morphology in practical applications.
