共查询到10条相似文献,搜索用时 125 毫秒
1.
Optimization procedure is one of the key techniques to address the computational and organizational complexities of multidisciplinary
design optimization (MDO). Motivated by the idea of synthetically exploiting the advantage of multiple existing optimization
procedures and meanwhile complying with the general process of satellite system design optimization in conceptual design phase,
a multistage-multilevel MDO procedure is proposed in this paper by integrating multiple-discipline-feasible (MDF) and concurrent
subspace optimization (CSSO), termed as MDF-CSSO. In the first stage, the approximation surrogates of high-fidelity disciplinary
models are built by disciplinary specialists independently, based on which the single level optimization procedure MDF is
used to quickly identify the promising region and roughly locate the optimum of the MDO problem. In the second stage, the
disciplinary specialists are employed to further investigate and improve the baseline design obtained in the first stage with
high-fidelity disciplinary models. CSSO is used to organize the concurrent disciplinary optimization and system coordination
so as to allow disciplinary autonomy. To enhance the reliability and robustness of the design under uncertainties, the probabilistic
version of MDF-CSSO (PMDF-CSSO) is developed to solve uncertainty-based optimization problems. The effectiveness of the proposed
methods is verified with one MDO benchmark test and one practical satellite conceptual design optimization problem, followed
by conclusion remarks and future research prospects. 相似文献
2.
Comparison of MDO methods with mathematical examples 总被引:1,自引:0,他引:1
Recently, engineering systems are quite large and complicated. The design requirements are fairly complex and it is not easy
to satisfy them by considering only one discipline. Therefore, a design methodology that can consider various disciplines
is needed. Multidisciplinary design optimization (MDO) is an emerging optimization method that considers a design environment
with multiple disciplines. Seven methods have been proposed for MDO. They are Multiple-discipline-feasible (MDF), Individual-discipline-feasible
(IDF), All-at-once (AAO), Concurrent subspace optimization (CSSO), Collaborative optimization (CO), Bi-level integrated system
synthesis (BLISS), and Multidisciplinary design optimization based on independent subspaces (MDOIS). Through several mathematical
examples, the performances of the methods are evaluated and compared. Specific requirements are defined for comparison and
new types of mathematical problems are defined based on the requirements. All the methods are coded and the performances of
the methods are compared qualitatively and quantitatively. 相似文献
3.
4.
Liansheng Li Ji Hong Liu Shaohua Liu 《Structural and Multidisciplinary Optimization》2014,49(2):239-252
The conventional reliability-based multidisciplinary design optimization (RBMDO) integrates the reliability-based design optimization and multidisciplinary design optimization (MDO) directly, which leads to a triple-level nested optimization loop. Especially, the multidisciplinary reliability analysis in the middle layer dominates the whole efficiency of RBMDO. To tackle this problem, first of all, a sequential multidisciplinary reliability analysis (SMRA) approach that integrates the concurrent subspace optimization (CSSO) strategy and the performance measure approach is proposed, in which the multidisciplinary analysis, system sensitivity analysis and reliability analysis are decoupled and arranged sequentially, making a recursive loop. The multidisciplinary analysis and system sensitivity analysis provide the value and gradient information of limit-state function for reliability analysis respectively. As a result, a great number of repeated iterations of the whole reliability analysis are eliminated. Secondly, the CSSO has been integrated with the sequential optimization and reliability assessment (SORA) to decouple the triple-level nested RBMDO procedures into a sequence of cycles of deterministic MDO and multidisciplinary reliability analysis. Therefore, the expensive computation of the whole reliability analysis model in each iteration of RBMDO is avoided. And also, the CSSO is adopted in the deterministic MDO to deal with medium-scale and coupled multidisciplinary systems. The procedures of the proposed approaches are presented in detail. The effectiveness of the proposed strategies is demonstrated and verified with two design examples. 相似文献
5.
Mathieu Balesdent Nicolas Bérend Philippe Dépincé Abdelhamid Chriette 《Structural and Multidisciplinary Optimization》2012,45(5):619-642
Optimal design of launch vehicles is a complex problem which requires the use of specific techniques called Multidisciplinary
Design Optimization (MDO) methods. MDO methodologies are applied in various domains and are an interesting strategy to solve
such an optimization problem. This paper surveys the different MDO methods and their applications to launch vehicle design.
The paper is focused on the analysis of the launch vehicle design problem and brings out the advantages and the drawbacks
of the main MDO methods in this specific problem. Some characteristics such as the robustness, the calculation costs, the
flexibility, the convergence speed or the implementation difficulty are considered in order to determine the methods which
are the most appropriate in the launch vehicle design framework. From this analysis, several ways of improvement of the MDO
methods are proposed to take into account the specificities of the launch vehicle design problem in order to improve the efficiency
of the optimization process. 相似文献
6.
Jonathon Leverenz Meng Xu Margaret M. Wiecek 《Structural and Multidisciplinary Optimization》2016,54(4):795-810
The area of Multiparametric Optimization (MPO) solves problems that contain unknown problem data represented by parameters. The solutions map parameter values to optimal design and objective function values. In this paper, for the first time, MPO techniques are applied to improve and advance Multidisciplinary Design Optimization (MDO) to solve engineering problems with parameters. A multiparametric subgradient algorithm is proposed and applied to two MDO methods: Analytical Target Cascading (ATC) and Network Target Coordination (NTC). Numerical results on test problems show the proposed parametric ATC and NTC methods effectively solve parametric MDO problems and provide useful insights to designers. In addition, a novel Two-Stage ATC method is proposed to solve nonparametric MDO problems. In this new approach elements of the subproblems are treated as parameters and optimal design functions are constructed for each one. When the ATC loop is engaged, steps involving the lengthy optimization of subproblems are replaced with simple function evaluations. 相似文献
7.
In complex engineering optimization, multilevel or two-level approaches are often applied. These approaches are carried out in assumption that there are no connections among sub problems at the same level. But it is difficult to construct the models that suit to this assumption. In recent years, the complexity of engineering systems has led to the rapid development in the field of Multidisciplinary Design Optimization (MDO). In MDO, two kinds of coupled factors, coupled variables (or functions) and system (or global) variables, always exist among all disciplines. These variable5 or functions make it disordered to solve the whole system. So, how to handle these variables is one of important studies in MDO. In this paper two approaches are discussed for handling these coupled factors in non-hierarchic system in MDO. And a test engineering example gives a demonstration about the implemeniation of these approaches. 相似文献
8.
With higher reliability and safety requirements, reliability-based design has been increasingly applied in multidisciplinary
design optimization (MDO). A direct integration of reliability-based design and MDO may present tremendous implementation
and numerical difficulties. In this work, a methodology of sequential optimization and reliability assessment for MDO is proposed
to improve the efficiency of reliability-based MDO. The central idea is to decouple the reliability analysis from MDO with
sequential cycles of reliability analysis and deterministic MDO. The reliability analysis is based on the first-order reliability
method (FORM). In the proposed method, the reliability analysis and the deterministic MDO use two MDO strategies, the multidisciplinary
feasible approach and the individual disciplinary feasible approach. The effectiveness of the proposed method is illustrated
with two example problems. 相似文献
9.
With the increased complexity of complex engineering systems (CES), more and more disciplines, coupled relationships, work processes, design data, design knowledge and uncertainties are involved. Currently, the MDO is facing unprecedented challenges especially in dealing with the CES by different specialists dispersed geographically on heterogeneous platforms with different analysis tools. The product design data integration and data sharing among the participants and the workflow optimization hamper the development and applications of MDO in enterprises seriously. Therefore, a multi-hierarchical integrated product design data model (MiPDM) supporting the MDO in web environment and a web services-based MDO framework considering aleatory and epistemic uncertainties are proposed in this paper. With the enabling technologies including web services, ontology, workflow, agent, XML, and evidence theory, the proposed framework enables the designers geographically dispersed to work collaboratively in the MDO environment. The ontology-based workflow enables the logical reasoning of MDO to be processed dynamically. Finally, a proof-of-concept prototype system is developed based on Java 2 Platform Enterprise Edition (J2EE) and an example of supersonic business jet is demonstrated to verify the web services-based MDO framework. 相似文献
10.
多学科优化设计也是在传统设计优化基础上重要的质的发展。它是设计方法、传统机械设计知识、过程设计知识、现代信息技术交叉集成的大系统方法。多学科设计优化技术 以提高产品性能、缩短设计周期和降低研制成本为目的。本文将多学科优化设计与传统优化设计进行对比,并以实例分别进行多学科设计优化和传统优化设计,证明了多学 科优化设计的可行性和高效性. 相似文献