J4 ›› 2015, Vol. 12 ›› Issue (4): 634-642.doi: 10.1016/S1672-6529(14)60153-0

• 论文 • 上一篇    下一篇

Synergistic Effects of Chiral Morphology and Reconfiguration in Cattail Leaves

Zilong Zhao1,2, Weixi Huang1, Bingwei Li1, Kexing Chen1, Kuifu Chen3, Hongping Zhao1, Xiqiao Feng1,2   

  1. 1. AML, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
    2. Center for Nano and Micro Mechanics, Tsinghua University, Beijing 100084, China
    3. College of Sciences, China Agricultural University, Beijing 100083, China
  • 收稿日期:2015-01-12 修回日期:2015-09-12 出版日期:2015-10-10 发布日期:2015-10-10
  • 通讯作者: Hongping Zhao, Xiqiao Feng E-mail:zhaohp@tsinghua.edu.cn, fengxq@tsinghua.edu.cn
  • 作者简介:Zilong Zhao1,2, Weixi Huang1, Bingwei Li1, Kexing Chen1, Kuifu Chen3, Hongping Zhao1, Xiqiao Feng1,2

Synergistic Effects of Chiral Morphology and Reconfiguration in Cattail Leaves

Zilong Zhao1,2, Weixi Huang1, Bingwei Li1, Kexing Chen1, Kuifu Chen3, Hongping Zhao1, Xiqiao Feng1,2   

  1. 1. AML, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
    2. Center for Nano and Micro Mechanics, Tsinghua University, Beijing 100084, China
    3. College of Sciences, China Agricultural University, Beijing 100083, China
  • Received:2015-01-12 Revised:2015-09-12 Online:2015-10-10 Published:2015-10-10
  • Contact: Hongping Zhao, Xiqiao Feng E-mail:zhaohp@tsinghua.edu.cn, fengxq@tsinghua.edu.cn
  • About author:Zilong Zhao1,2, Weixi Huang1, Bingwei Li1, Kexing Chen1, Kuifu Chen3, Hongping Zhao1, Xiqiao Feng1,2

摘要:

Cattail, a type of herbaceous emergent aquatic macrophyte, has upright-standing leaves with a large slenderness ratio and a chiral morphology. With the aim of understanding the effect of chiral morphology on their mechanical behavior, we investi-gated, both experimentally and theoretically, the twisting chiral morphologies and wind-adaptive reconfigurations of cattail leaves. Their multiscale structures were observed by using optical microscope and scanning electron microscopy. Their me-chanical properties were measured by uniaxial tension and three-point bending tests. By modeling a chiral leaf as a pre-twisted cantilever-free beam, fluid dynamics simulations were performed to elucidate the synergistic effects of the leaf’s chiral mor-phology and reconfiguration in wind. It was observed that the leaves have evolved multiscale structures and superior mechanical properties, both of which feature functionally gradient variations in the height direction, to improve their ability to resist lodging failure by reducing the maximal stress. The synergistic effect of chiral morphology and reconfiguration can greatly improve the survivability of cattail plants in wind.

关键词: cattail, chiral morphology, reconfiguration, fluid-structure interaction, lodging resistance

Abstract:

Cattail, a type of herbaceous emergent aquatic macrophyte, has upright-standing leaves with a large slenderness ratio and a chiral morphology. With the aim of understanding the effect of chiral morphology on their mechanical behavior, we investi-gated, both experimentally and theoretically, the twisting chiral morphologies and wind-adaptive reconfigurations of cattail leaves. Their multiscale structures were observed by using optical microscope and scanning electron microscopy. Their me-chanical properties were measured by uniaxial tension and three-point bending tests. By modeling a chiral leaf as a pre-twisted cantilever-free beam, fluid dynamics simulations were performed to elucidate the synergistic effects of the leaf’s chiral mor-phology and reconfiguration in wind. It was observed that the leaves have evolved multiscale structures and superior mechanical properties, both of which feature functionally gradient variations in the height direction, to improve their ability to resist lodging failure by reducing the maximal stress. The synergistic effect of chiral morphology and reconfiguration can greatly improve the survivability of cattail plants in wind.

Key words: cattail, chiral morphology, reconfiguration, fluid-structure interaction, lodging resistance