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航天器模块划分数值优化方法 总被引:1,自引:0,他引:1
对航天器模块划分主要依靠经验和定性方法的问题,构建了一种通用的模块划分数值优化方法。利用功能分解方法、相关性评价准则、设计矩阵与设计结构矩阵(DesignStructureMatrix,DSM)同步演化的机制获得了基于功能元的数值DSM;基于DSM构建了遵循公理化设计原理的通用优化模型;利用遗传 模拟退火算法获得了可对模块划分方式及数目进行同步优化的模块划分方法;给出了不同于优化目标的评价方法。仿真结果表明,该方法可将航天器划分为一系列内聚度高、耦合度低的模块。 相似文献
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航空电子设备用于飞行中的数据采集,通常使用安装支架固定于机头雷达罩,研究安装支架的刚度和一阶频率性能,避免设备支架在飞行过程中出现塑性变形和共振现象,对提高飞行稳定性具有重要的工程意义。在惯性载荷下对安装支架进行静强度和模态分析,采用一种灵敏度分析方法确定安装支架的设计变量,以结构总质量最小为优化目标,在保证安装支架的刚度和一阶模态性能的前提下对支架各个构件的厚度进行优化设计,并对优化后的安装支架结构进行振动试验。结果表明:优化后的安装支架结构刚度基本保持不变,一阶频率提高了18.09%,质量减少了19.33%,改进设计满足设备安装要求。 相似文献
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设备软件的质量控制工作是设备总体工作不可缺少的一部分,它直接影响产品的使用质量和维护成本。本文从软件工程化管理角度出发,结合设备总体工作实践和软件测试工作实践,提出了在设备软件研制的不同阶段应该特别关注的质量要素,对设备总体工作人员具有一定的帮助。 相似文献
448.
J.Roshanian Z.Keshavarz 《中国航空学报》2007,20(1):86-96
Different multidisciplinary design optimization (MDO) problems are formulated and compared. Two MDO formulations are applied to a sounding rocket in order to optimize the performance of the rocket. In the MDO of the referred vehicle, three disciplines have been considered,which are trajectory, propulsion and aerodynamics. A special design structure matrix is developed to assist data exchange between disciplines. This design process uses response surface method (RSM) for multidisciplinary optimization of the rocket. The RSM is applied to the design in two categories: the propulsion model and the system level. In the propulsion model, RSM deter-mines an approximate mathematical model of the engine output parameters as a function of design variables. In the system level, RSM fits a surface of objective function versus design variables. In the first MDO problem formulation, two design variables are selected to form propulsion discipline. In the second one, three new design variables from geometry are added and finally, an optimization method is applied to the response surface in the system level in order to find the best result. Application of the first developed multidisciplinary design optimization procedure increased accessible altitude (performance index) of the referred sounding rocket by twenty five percents and the second one twenty nine. 相似文献
449.
Toufik Zebbiche ZineEddine Youbi 《中国航空学报》2007,20(1):29-39
When the stagnation temperature of a perfect gas increases, the specific heat ratio does not remain constant any more, and start to vary with this temperature. The gas remains perfect, its state equation remains always valid, except it will name in more calorically im-perfect gas or gas at High Temperature. The goal of this work is to trace the profiles of the supersonic Minimum Length Nozzle with centered expansion when the stagnation temperature is taken into account, lower than the threshold of dissociation of the molecules and to have for each exit Mach number several nozzles shapes by changing the value of the temperature. The method of characteristics is used with a new form of the Prandtl Meyer function at high temperature. The resolution of the obtained equations is done by the second order of finite differences method by using the predictor corrector algorithm. A study on the error given by the perfect gas model com-pared to our model is presented. The comparison is made with a calorically perfect gas for goal to give a limit of application of this model. The application is for the air. 相似文献
450.
CHENG Wen-yuan CHANG Yan CUI De-gang XIE Xiang-hui 《中国航空学报》2007,20(1):55-59
To solve the topology optimization of complicated multi-objective continuous/discrete design variables in aircmit structure design, a Parallel Pareto Genetic Algorithm (PPGA) is presented based on grid platform in this paper. In the algorithm, the commercial finite element analysis (FEA) software is integrated as the calculating tool for analyzing the objective functions and the filter of Pareto solution set based on weight information is introduced to deal with the relationships among all objectives. Grid technology is utilized in PPGA to realize the distributed computations and the user interface is developed to realize the job submission and job management locally/remotely. Taking the aero-elastic tailoring of a composite wing for optimization as an example, a set of Pareto solutions are obtained for the decision-maker. The numerical results show that the aileron reversal problem can be solved by adding the limited skin weight in this system. The algorithm can be used to solve complicated topology optimization for composite structures in engineering and the computation efficiency can be improved greatly by using the grid platform that aggregates numerous idle resources. 相似文献