Torsional Vibration of Functionally Porous Nanotube Based on Nonlocal Couple Stress Theory

Abstract

Presented in this paper is a numerical solution for torsional vibration analysis of a functionally porous nanotube under a magnetic field. The size effect in microscale can be captured using the nonlocal couple stress theory that predicts softening and hardening in micro-size. The torsional vibration of functionally porous nanotube with magnetic field based on nonlocal couple stress theory is examined. The governing equation is derived using Hamilton’s principle and the generalized differential quadrature method (GDQM) was employed to solve it. A comparison between the results of this work with the other paper reveals the accuracy of this study. The effects of some parameters such as porosity, magnetic field, and small-scale parameters were investigated. The results show that different materials have different behavior in micro-size that can be covered softening and hardening.