MODELS AND TOOLS FOR HEAT TRANSFER,THERMAL STRESSES,AND STABILITY OF COMPOSITE AEROSPACE STRUCTURES

An overview of DLR's current research activities and results in the fields of heat transfer, thermal stresses, and thermally induced buckling in composite aerospace structures is given. Novel theories and finite element formulations are presented, realistic modeling of boundary conditions and junction areas is highlighted, experimental validation is discussed, and design guidelines are given.     

Material Behaviour: Embedding Physical Properties in Computational Design Processes

Material behaviour computes form. In the physical world, material form is always inseparably connected to internal constraints and external forces; in the virtual space of digital design, though, form and force are usually treated as separate entities – divided into processes of geometric form generation and subsequent engineering simulation. Using the example of the interdisciplinary ICD/ITKE Research Pavilion, constructed at the University of Stuttgart in 2010, Moritz Fleischmann, Jan Knippers, Julian Lienhard, Achim Menges and Simon Schleicher explain how feedback between computational design, advanced simulation and robotic fabrication expands the design space towards previously unexplored architectural possibilities. Copyright © 2012 John Wiley & Sons, Ltd.     

一种基于离散实镜像理论的修正物理光学法在金属平行板内嵌电大尺寸结构中的应用

传统的物理光学法(PO)能够方便高效地处理开放空间中电大尺寸结构的电磁散射问题,并且通常能获得较好的精度。然而,对于电大尺寸结构内嵌在金属平行板之间的这种特殊问题,传统的PO方法不再适用,而采用全波分析方法来处理往往需要消耗巨大的计算资源。该文在离散实镜像理论的基础上,提出了一种修正的物理光学法(DRMI-PO),基本思想是先将金属平行板间的激励电磁流展开为傅里叶级数,再对级数的每一项分别应用2维物理光学法求解场,最后把所有求得的场解作线性组合。与多层快速多极子(MLFMA)的全波方法相比,DRMI-PO在解决该类特殊结构的电磁仿真问题时能在保证足够高精度的同时大幅度提高计算效率;作为应用实例,对两种不同极化方式的太赫兹波段扇形波束扫描天线分别进行了DRMI-PO数值仿真与实验测试,结果表明仿真和实验得出的天线方向图吻合较好,从而证实了DRMI-PO方法的有效性。