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排序方式: 共有1018条查询结果,搜索用时 46 毫秒
51.
Evolutionary topology optimization for temperature reduction of heat conducting fields 总被引:2,自引:0,他引:2
Qing Li Grant P. Steven Osvaldo M. Querin 《International Journal of Heat and Mass Transfer》2004,47(23):5071-5083
This paper aims at developing an efficient finite element based computational procedure for the topology design of heat conducting fields. To evaluate the temperature change in a specific position, due to varying the conducting material distribution in other regions, a discrete temperature sensitivity is derived for an evolutionary topology optimization method. In the topology optimization of the conducting fields, the thermal conductivity of an individual finite element is considered as the design variable. By removing or degenerating the conductive material of the elements with the most negative sensitivity, the temperature objective at the control point can be most efficiently reduced. Illustrative examples are presented to demonstrate this proposed approach. 相似文献
52.
根据城域网网管软件开发过程中的设计经验,本文阐述了一种基于路由接口地址空间和SNMP异步扫描的网络物理拓扑快速发现的方法,并在具体项目中予以实现和应用,解决了拓扑发现过程中面临的设备搜索的完整性、拓扑发现的速度和拓扑判定的准确性三个主要问题,并取得了良好的效果。 相似文献
53.
以基于结构重用实现产品快速变异设计为目标,在前人研究成果的基础上,提出了基于特征单元移植的结构变异设计系统的构建模型,对其体系结构及其实现的关键技术进行了探讨。详细阐述了特征单元建模技术中特征单元信息模型、特征单元库的建立方法,并根据箱体类零件的功能和结构特点构建了箱体类零件的特征单元库;分析了组成变异零件基型的特征单元之间的布尔运算类型以及特征单元的具体分割操作过程;描述了通过切合面类型的判断,实现变异零件基型与移植特征单元的拓扑搭接操作过程。最后,通过一个箱体类零件结构变异的实例,说明了该系统实现零件结构变异设计的基本过程。 相似文献
54.
Yamazaki Koestu 《机械工程学报(英文版)》2005,18(2):187-191
The biotic branch nets are extreme high-tech product. In order to achieve a certain functional objective, they can adjust their growth direction and growth velocity by according to the varying growth environment. An innovative and effective methodology of topology design optimization based on the growth mechanism of biotic branch nets is suggested, and it is applied to a layout design problem of a conductive cooling channel in a heat transfer system. The effectiveness of the method is validated by the FEM analysis. 相似文献
55.
A topological derivative method for topology optimization 总被引:4,自引:2,他引:2
Julian A. Norato Martin P. Bendsøe Robert B. Haber Daniel A. Tortorelli 《Structural and Multidisciplinary Optimization》2007,33(4-5):375-386
We propose a fictitious domain method for topology optimization in which a level set of the topological derivative field for
the cost function identifies the boundary of the optimal design. We describe a fixed-point iteration scheme that implements
this optimality criterion subject to a volumetric resource constraint. A smooth and consistent projection of the region bounded
by the level set onto the fictitious analysis domain simplifies the response analysis and enhances the convergence of the
optimization algorithm. Moreover, the projection supports the reintroduction of solid material in void regions, a critical
requirement for robust topology optimization. We present several numerical examples that demonstrate compliance minimization
of fixed-volume, linearly elastic structures. 相似文献
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59.
建筑形态的拓扑同胚演化 总被引:5,自引:0,他引:5
拓扑学给当今建筑界带来深刻的变革,这种变革不仅表现在建筑形态上,更重要的是对整个建筑体系的冲击。本文主要从介绍拓扑学的核心问题即同胚变换入手,阐明了拓扑学同胚变换时建筑形态的表现形式,并进一步说明了导致建筑形态同胚变换的深层原因,指出同胚变换是建筑形态变化的深层结构。 相似文献
60.
Zhen Luo Li-Ping Chen Jingzhou Yang Yun-Qing Zhang 《The International Journal of Advanced Manufacturing Technology》2006,30(3-4):203-214
This paper presents a new multi-objective topology optimization algorithm for continuum structures under multiple loading cases. An expert evaluation method of weights based on grey system theory is proposed to calculate the objective weights when the compromise programming approach is employed as a multi-objective optimization scheme converting the multi-objective problem to a single objective problem. A modified updating scheme with a self-adaptive move limit for design variables is also suggested, SIMP is regarded as density-stiffness interpolation scheme and the optimality criteria method is used as the optimizer. Numerical instabilities, such as checkerboards and mesh dependencies, are also discussed. The validities of these methods in this paper are demonstrated by some numerical applications. 相似文献