空间螺旋式弹性传热管束模态与应力特性分析

弹性管束换热器利用流体诱导振动实现强化传热,弹性管束的结构优化、模态及应力特性等对弹性管束的使用寿命具有重要影响。基于此,提出一种新型空间螺旋式弹性传热元件,通过ANSYS有限元模拟技术,分析了空间螺旋管束的固有模态特性以及在一定振幅条件下管束的应力分布特性,并与现有的平面弹性管束进行比较。结果表明,在相同尺寸下,空间螺旋式弹性管束固有频率较低,以纵向振动为主;管束的应力分布均匀,最大应力发生在管程流体进出口固定端,其最大应力仅为平面弹性管束的1/4左右。

“迷失”的螺旋空间——东京武藏野美术大学图书馆解析

藤本壮介是日本新生代建筑师中最具才华者之一,他的作品传达了强烈的关于空间的哲学思考,先后提出了“原始的未来”“暧昧空间”等理论。本文通过对该图书馆设计概念、空间建构、细部处理三部分进行分析,重点研究了两个常出现在藤本壮介作品中的主题,即“弱建筑”与“迷失性”是如何体现在该作品中空间设计中。

Computational Simulation of Complex Structure Fancy Yarns

A study is reported for mathematical model and simulative of complex structure fancy yams. The investigated complex structure fancy yams have a multithread structure composed of three components core, effect, and binder yams. In current research the precondition was accepted that the cross-sections of the both two yams of the effect intermediate product in the complex structure fancy yam remain the circles shaped, and this shape does not change during manufacturing of the fancy yam. Mathematical model of complex structure fancy yarn is established based on parameter equation of space helix line and computer simulative is further carried out using the computational mathematical tool Matlab 6.5. Theoretical structure of fancy yam is compared with an experimental sample. The simulative system would help for further the set of informative in designing of new assortment of the complex structure fancy yarns and prediction of visual effects of fancy yams in end-use fabrics.