Energy absorption induced oscillation of a rotating curved carbon nanotube in a nano bearing

In a nano bearing, a curved inner carbon nano tube (CNT) constrained by two short outer CNTs will have an oscillation along the curved axis of the tube when a specified rotational velocity is input on one end of the inner tube. It is found that the free end has periodic axial translational oscillation and the amplitude of oscillation is very high when the frequency of the input rotational velocity is close to an eigen/resonance frequency of the system, i.e., energy absorption of the inner tube from the interaction between the inner and outer tubes. Higher curvature of the inner tube leads to higher value of fundamental frequency of the system. The free end of the inner tube also has obvious torque oscillation. Both of the axial translational oscillation and torque oscillation of the free end can be used as output signals of the system as working in a nano signal generator. The mid part of the inner tube, i.e., the part between two outer tubes, has obvious in-plane vibration, which indicates that the present nano bearing is a two-dimensional device. (C) 2015 Elsevier B.V. All rights reserved.