Iranian Journal of Mechanical Engineering Transactions of ISME

Iranian Journal of Mechanical Engineering Transactions of ISME

Effect of geometrical parameters on natural frequencies of sandwich beam with composite faces reinforced with FG-CNT and two types of stiff and flexible core

Author
sajjad etehadi
shahrekord university
Abstract
In this article, the vibrational behavior of sandwich beams with stiff and flexible core and face sheets reinforced with carbon nanotubes has been investigated. Carbon nanotubes are used as materials that their properties change along the thickness. In this research for modelling the sandwich beam an extended high order sandwich theory is used. In order to model the behavior of faces the Timoshenko beam’s theory is employed and also for modeling the behavior of the core, three-degree displacement field is used considering the axial stresses and also compatibility conditions of the core. The equations of motion are derived using the variations of energy and the Ritz method is used to solve the equations of motion. The obtained results are compared with available results that show the high accuracy of the present modelling. The results for different distributions of carbon nanotubes and different boundary conditions have been investigated. In this research new results are presented for different boundary conditions in terms of different length to thickness ratio. One of the important result of this research is that, generally it cannot be say that what distribution of CNT leads to maximum or minimum natural frequency of the structure and this problem is strongly depended on the length to thickness ratio of the bam and also stiffness or flexibility of the core.
Keywords
frequency analysis
FG-CNT
stiff and flexible core
extended high order sandwich theory

Subjects

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Iranian Journal of Mechanical Engineering Transactions of ISME
Volume 21, Issue 3 - Serial Number 56
System Dynamics and Solid Mechanics
Autumn 2019
Pages 101-137

  • Receive Date 11 January 2018
  • Revise Date 10 February 2018
  • Accept Date 19 January 2020