Laminated Composite Stiffened Cylindrical Shell Panels with Cutouts under Free Vibration

Laminated Composite Stiffened Cylindrical Shell Panels with Cutouts under Free Vibration

Sarmila Sahoo (Heritage Institute of Technology, Kolkata, India)
DOI: 10.4018/IJMMME.2015070103
OnDemand PDF Download:
$37.50

Abstract

The free vibration of laminated composite stiffened cylindrical shell panels in the presence of cutout is investigated. A finite element code is developed using eight-noded curved quadratic isoparametric element for shell with a three noded beam element for stiffener and the formulation is validated through solution of benchmark problems which were earlier solved by other researchers. Parametric study is carried out varying the size of the cutouts and their positions with respect to the shell centre for different edge constraints. The results are presented in the form of figures and tables. The results are further analyzed to suggest guidelines to select optimum size and position of the cutout with respect to shell centre considering the different practical constraints.
Article Preview

Notations

  • a, b: Length and width of shell in plan

  • : Length and width of cutout in plan

  • bst: Width of stiffener in general

  • bsx, bsy: Width of X and Y stiffeners respectively

  • dst: Depth of stiffener in general

  • dsx, dsy: Depth of X and Y stiffeners respectively

  • {de}: Element displacement

  • E11, E22: Elastic moduli

  • G12, G13, G23: Shear moduli of a lamina with respect to 1, 2 and 3 axes of fibre

  • H: Shell thickness

  • Mx, My: Moment resultants

  • Mxy: Torsion resultant

  • Np: Number of plies in a laminate

  • N1-N8: Shape functions

  • Nx,, Ny: Inplane force resultants

  • Nxy: Inplane shear resultant

  • Qx, Qy: Transverse shear resultant

  • Ry,: Radii of curvature of shell

  • u, v, w: Translational degrees of freedom

  • x, y, z: Local co-ordinate axes

  • X, Y, Z: Global co-ordinate axes

  • zk: Distance of bottom of the kth ply from mid-surface of a laminate

  • α,β: Rotational degrees of freedom

  • εx, εy: Inplane strain component

  • γxy, γxz, γyz: Shearing strain components

  • ν12, ν21: Poisson’s ratios

  • ξ, η, τ: Isoperimetric co-ordinates

  • ρ: Density of material

  • σx, σy: Inplane stress components

  • τxy, τxz, τyz: Shearing stress components

  • ω: Natural frequency

  • : Non-dimensional natural frequency

Complete Article List

Search this Journal:
Reset
Open Access Articles: Forthcoming
Volume 7: 4 Issues (2017)
Volume 6: 4 Issues (2016)
Volume 5: 4 Issues (2015)
Volume 4: 4 Issues (2014)
Volume 3: 4 Issues (2013)
Volume 2: 4 Issues (2012)
Volume 1: 4 Issues (2011)
View Complete Journal Contents Listing