基于非局部效应和表面效应的输流碳纳米管稳定性分析简

应用非局部黏弹性夹层梁模型分析双参数弹性介质中输送脉动流碳纳米管的稳定性. 新模型中同时考虑了由管道内、外壁上的薄表面层引起的表面弹性效应和表面残余应力,经典的欧拉梁模型因此通过引入非局部参数和表面参数得到了改进. 用平均法对其控制方程进行求解,得到了管道稳定性区域. 数值算例揭示了纳米材料的非局部效应、表面效应及两个弹性介质参数对管道固有频率、临界流速和动态稳定性的复杂影响,结论可为纳米流体机械的结构设计和振动分析提供理论基础.

STABILITY ANALYSIS OF A FLUID-CONVEYING CARBON NANOTUBE WITH CONSIDERATION OF NONLOCAL AND SURFACE EFFECTS

In this paper, a nonlocal viscoelastic sandwich-beam model is developed to investigate the stability of a pulsating-fluid-conveying carbon nanotube (CNT) embedded in two-parameter elastic mediums. In the new model, thin surface layers are on the inner and outer tube surfaces and both the resulting effects of the surface elasticity and the surface residual stress are taken into account. The classical Euler-Bernoulli beam model is modified by introducing nonlocal and surface parameters. The governing equation is solved via the averaging method and the stability regions are obtained. Numerical examples show the complicated influences of the nonlocal, surface effects and the two medium parameters on the natural frequency, the critical flow velocity and the dynamic stability of the CNT. The conclusions of the present paper may be used in the structural design and vibration analysis of nanofluidic devices.