碳纳米管质量传感器振动特性研究  

Investigation on the Vibration of Carbon Nanotube Based Mass Sensors

作　　者：陈越[1] 李明林[1] 

机构地区：[1]福州大学机械工程及自动化学院,福建福州350108

出　　处：《机械制造与自动化》2015年第5期171-175,共5页Machine Building & Automation

基　　金：国家自然科学青年科学基金课题(50903017)

摘　　要：基于欧拉-伯努利梁理论对单壁碳纳米管质量传感器的振动特性进行研究。分别考虑悬臂梁式和两端固定式碳纳米管质量传感器,研究吸附质量对其谐振频率漂移的影响。推导出任意位置的吸附质量下,碳纳米管质量传感器的等效刚度、等效质量和谐振频率的解析表达式,推导出传感器的非线性应用方程及其简化形式。在特定位置下吸附质量对不同长度碳纳米管谐振频率的影响进行了研究。数值仿真结果表明,对于不同的边界约束和特定的吸附位置条件下,吸附质量越大、碳纳米管的长度越短,导致的碳纳米管频率漂移越大。对于8 nm长的碳纳米管,在悬臂式约束下,吸附质量越远离固定端,引起的频率漂移越大。而在两端固定约束下,则是吸附质量越靠近固定端,频率漂移越大。揭示了传感器的谐振特性,有助于促进碳纳米管在纳机谐振器领域的推广应用。Vibrational properties of single-walled carbon nanotubes （SWCNTs） as a mass sensor is examined using Euler - Bernoulli beam theory based approach. In order to figure out how the attached mass affects the resonant frequency of the carbon nano- tube resonators, the resonators both in bridged and in cantilevered configurations are studied. Firstly, analytical formulas of equiva-lent stiffness, equivalent mass and resonant frequency are developed for CNT-based nanoresonators with attached mass at any location. In addition, a simplified form of the nonlinear sensor equation and image analysis of the relationship among load location, the attached mass and resonant frequency have been investigated. Then for different lengths of SWCNTs, the influence of the attached mass in a specific location on the resonant frequency has been derived. The simulation results indicate that in the condition of differ- ent boundary constraints and the specific adsorption location, the heavier attached mass and shorter carbon nanotube is,the greater frequency drift will be. As for the nanotube of 8nm, the attached mass which is farther away from the fixed boundary causes the greater frequency drift in cantilevered. While the attached mass closer to the fixed boundary causes the greater frequency driff in bridged. The results illustrate that the new vibrational properties can be used for CNT-based mass sensors for further promote application.

关 键 词：单壁碳纳米管 质量传感器 欧拉-伯努利梁理论 谐振频率 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]