Thermoelastic free vibration of rotating pretwisted sandwich conical shell panels with functionally graded carbon nanotube-reinforced composite face sheets using higher-order shear deformation theory

Abstract

This article presents a numerical investigation on the free vibration characteristics of rotating pretwisted sandwich conical shell panels with two functionally graded carbon nanotube-reinforced composite (FG-CNTRC) face sheets and a homogeneous core in uniform thermal environments. The carbon nanotubes are considered to be aligned with the span length and distributed either uniformly or functionally graded along the thickness of the sandwich conical shell panel. The material properties of FG-CNTRC face sheets and homogenous core are assumed to be temperature-dependent and computed employing micromechanics models. The shallow conical shell is modeled using finite element method within a framework of the higher-order shear deformation theory. Lagrange’s equation of motion is employed to derive the dynamic equilibrium equations of sandwich conical shell panels rotating at moderate rotational speeds wherein Coriolis effect is neglected. Computer codes are developed on the basis of present mathematical formulation to determine the natural frequencies of the sandwich conical panels. Convergence and comparison studies are performed to examine the consistency and accurateness of the present formulation. The numerical results are presented to analyze the effects of various parameters on the natural frequencies of the pretwisted FG-CNTRC sandwich conical shell panels under different thermal conditions.

Transient response of pre-twisted FG-GRC sandwich conical shell subjected to low-velocity impact in thermal environment

“…The shell curvature radius in the y -direction r y ( x , y ) is dependent on both x and y coordinates and may be expressed as 65,66…”

“…61,62 However, cantilever pre-twisted open conical shells may be more appropriate models for the actual blades due to their variable chordwise curvature. [63][64][65][66][67] Bandyopadhyay et al 68 developed an FE procedure using Mindlin's plate theory to investigate the dynamic behavior of delaminated composite pretwisted conical shells subjected to multiple impacts in hygrothermal environments incorporating Green-Lagrange non-linear strains. The authors also included the modified indentation law in the FE formulation to evaluate the impact-induced contact force.…”

Conical-Shaped Shells of Non-Uniform Thickness Vibration Analysis Using Higher-Order Shear Deformation Theory

“…The free vibration of conical shells using HSDT in thermal surrounding were examined by Singha et al [13]. Deb Singha et al [14] analysed pre-twisted conical shells with functionally graded carbon nanotube. The frequencies of coupled conical shells have also been investigated (Gia Ninh [15] and Bagheri [16]).…”