Nonlocal shell model for elastic wave propagation in single- and double-walled carbon nanotubes
Nonlocal shell model for elastic wave propagation in single- and double-walled carbon nanotubes
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DOI：
10.1016/j.jmps.2008.08.010
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发表时间：
2008-12
影响因子：
5.3
通讯作者：
Yan-Gao Hu;K. Liew;Quan Wang;Xiaoqiao He;B. Yakobson
中科院分区：
文献类型：
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作者：
Yan-Gao Hu;K. Liew;Quan Wang;Xiaoqiao He;B. Yakobson
本文研究了单壁和双壁碳纳米管（SWCNTs和DWCNTs）中的横波和扭转波，重点研究了碳纳米管微结构对波频散的影响。单壁碳纳米管和多壁碳纳米管被建模为非局部单弹性和双弹性圆柱壳。分子动力学（MD）模拟结果表明，波的色散预测的非局部弹性圆柱壳理论显示出良好的协议与MD模拟在很宽的频率范围内的太赫兹区域。非局部弹性壳理论提供了一个更好的预测的色散关系比经典的壳理论时，波数是足够大的碳纳米管的微结构有一个显着的影响波的色散。对于扶手椅型（15，15）单壁碳纳米管中的横波和扶手椅型（10，10）单壁碳纳米管中的扭转波，当波长分别约小于2.36×10− 9和0.95×10− 9 m时，需要采用非局域壳模型.此外，基于MD的估计的比例系数e0的非局部弹性圆柱壳模型的建议。由于单壁碳纳米管的小尺度效应和层间货车德瓦耳斯相互作用，在高频波传播的MD模拟中可以观察到内外管中横波的相位差。而货车德瓦耳斯相互作用对横波相位差的影响很小。
This paper investigates the transverse and torsional wave in single- and double-walled carbon nanotubes (SWCNTs and DWCNTs), focusing on the effect of carbon nanotube microstructure on wave dispersion. The SWCNTs and DWCNTs are modeled as nonlocal single and double elastic cylindrical shells. Molecular dynamics (MD) simulations indicate that the wave dispersion predicted by the nonlocal elastic cylindrical shell theory shows good agreement with that of the MD simulations in a wide frequency range up to the terahertz region. The nonlocal elastic shell theory provides a better prediction of the dispersion relationships than the classical shell theory when the wavenumber is large enough for the carbon nanotube microstructure to have a significant influence on the wave dispersion. The nonlocal shell models are required when the wavelengths are approximately less than 2.36×10−9and 0.95×10−9m for transverse wave in armchair (15,15) SWCNT and torsional wave in armchair (10,10) SWCNT, respectively. Moreover, an MD-based estimation of the scale coefficient e0for the nonlocal elastic cylindrical shell model is suggested. Due to the small-scale effects of SWCNTs and the interlayer van der Waals interaction of DWCNTs, the phase difference of the transverse wave in the inner and outer tube can be observed in MD simulations in wave propagation at high frequency. However, the van der Waals interaction has little effect on the phase difference of transverse wave.