Buckling Analysis of Symmetric Cross-Ply Laminated Annular Plates with Carbon Nanotubes

2014 ◽  
Vol 592-594 ◽  
pp. 901-905
Author(s):  
Pankaj Kumar ◽  
Pandey Ramesh
Keyword(s):  
Carbon Nanotubes ◽  
Boundary Condition ◽  
Carbon Nanotube ◽  
Aspect Ratio ◽  
Energy Method ◽  
Buckling Analysis ◽  
Buckling Load ◽  
Buckling Loads ◽  
Annular Plates ◽  
Buckling Behavior

The Paper presents the buckling response of composite annular plates with under uniform internal and external radial edge loads using energy method. For the equation of stability Trefftez rule is used. The paper consists of buckling behavior of laminate (90/0) s, influence of some parameters such as thickness, boundary condition, aspect ratio on buckling loads and modes are investigated. Present results are compared with other papers. In this paper the effect of % weight of carbon nanotube (MWCNT) on the buckling load is also investigated.

Critical Buckling Load of Triple-Walled Carbon Nanotube Based on Nonlocal Elasticity Theory

2020 ◽  
Vol 62 ◽  
pp. 108-119
Author(s):  
Tayeb Bensattalah ◽  
Ahmed Hamidi ◽  
Khaled Bouakkaz ◽  
Mohamed Zidour ◽  
Tahar Hassaine Daouadji
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Axial Compression ◽  
Buckling Load ◽  
Small Scale ◽  
Beam Model ◽  
Buckling Loads ◽  
Critical Buckling Load ◽  
Nonlocal Continuum Theory ◽  
Walled Carbon Nanotubes

The present paper investigates the nonlocal buckling of Zigzag Triple-walled carbon nanotubes (TWCNTs) under axial compression with both chirality and small scale effects. Based on the nonlocal continuum theory and the Timoshenko beam model, the governing equations are derived and the critical buckling loads under axial compression are obtained. The TWCNTs are considered as three nanotube shells coupled through the van der Waals interaction between them. The results show that the critical buckling load can be overestimated by the local beam model if the small-scale effect is overlooked for long nanotubes. In addition, a significant dependence of the critical buckling loads on the chirality of zigzag carbon nanotube is confirmed, and these are then compared with: A single-walled carbon nanotubes (SWCNTs); and Double-walled carbon nanotubes (DWCNTs). These findings are important in mechanical design considerations and reinforcement of devices that use carbon nanotubes.

Buckling of fiber metal laminated plates – numerical and experimental studies

2020 ◽  
Vol 92 (3) ◽  
pp. 472-481
Author(s):  
Elluri Venkata Prasad ◽  
Shishir Kumar Sahu
Keyword(s):  
Aspect Ratio ◽  
Boundary Conditions ◽  
Thickness Ratio ◽  
Buckling Load ◽  
Element Formulation ◽  
Buckling Loads ◽  
Content Type ◽  
Buckling Behavior ◽  
Fiber Metal ◽  
Ply Orientation

Purpose The purpose of this study is to study the buckling behavior of new aircraft material, i.e. glass fiber metal laminated (GFML) plates. Design/methodology/approach The first-order Reissner–Mindlin theory is used in the present finite element formulation to determine the buckling loads of GFML plates. A program is developed in MATLAB for analyzing the effect of different parameters on buckling loads GFML plates. A set of experiments was performed to determine critical buckling loads of GFML plates using universal testing machine INSTRON 8862 and compared with predictions using the numerical model. Findings The effects of various parameters such as aspect ratio, side to thickness ratio, ply orientation and boundary conditions on buckling loads of GFMLs are examined. With the increase of aspect ratio, the reduction in buckling load is observed, while the increase inside to thickness ratio decreases the buckling load of GFML plates. There is a slight variation in buckling load with the increase of ply orientation. The buckling load is significantly influenced by boundary conditions because of restraint at the edges. Practical implications These types of materials are used in lightweight structures such as aircraft, aerospace and military vehicles. The results reported in the present study can be used as design guidelines while designing fiber metal laminated (FML) plated structures. Originality/value For the first time, the authors have studied the buckling behavior of bidirectional woven FML plates using both numerical and experimental techniques.

scholarly journals EFFECT OF HELICITY ON THE BUCKLING BEHAVIOR OF SINGLE-WALL CARBON NANOTUBES

2008 ◽  
Vol 22 (31n32) ◽  
pp. 5872-5877 ◽  
Author(s):  
JEEHYANG HUH ◽  
HOON HUH
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Young’S Modulus ◽  
Interatomic Potential ◽  
Young's Modulus ◽  
Compressive Force ◽  
Buckling Load ◽  
Single Wall Carbon Nanotubes ◽  
Single Wall Carbon ◽  
Buckling Behavior

Simulations of single-wall carbon nanotube(SWCNT)s having a different chiral vector under axial compression were carried out based on molecular dynamics to investigate the effect of the helicity on the buckling behavior. Calculation was performed at room temperature for (8,8) armchair, (14,0) zigzag and (6,10) chiral single-wall carbon nanotubes. The Tersoff potential was used as the interatomic potential since it describes the C - C bonds in carbon nanotubes reliably. A conjugate gradient (CG) method was used to obtain the equilibrium configuration. Compressive force was applied at the top of a nanotube by moving the top-most atoms downward with the constant velocity of 10m/s. The buckling load, the critical strain, and the Young's modulus were calculated from the result of MD simulation. A zigzag carbon nanotube has the largest Young's modulus and buckling load, while a chiral carbon nonotube has the lowest values.

Buckling Analysis of Wind Power Tower Considering the Effect of Nonlinearity

2012 ◽  
Vol 256-259 ◽  
pp. 792-795
Author(s):  
Bo Song ◽  
Shuai Huang ◽  
Wen Shan He ◽  
Wei Wei
Keyword(s):  
Wind Power ◽  
Geometric Nonlinearity ◽  
Local Buckling ◽  
Element Model ◽  
Buckling Analysis ◽  
Buckling Load ◽  
Nonlinear Buckling ◽  
Buckling Behavior ◽  
Geometry Nonlinearity ◽  
Material And Geometric Nonlinearity

Based on the 3D finite element model of the wind power tower, buckling behavior of the wind power tower in different wind directions is analyzed, and the effect considering geometry nonlinearity and considering the material and geometry nonlinearity to the buckling analysis is studied. The results show when the ratio of the radius of the tower drum and the length of the element is 18.75, the calculated precision can reach 95%. Local buckling of the wind power tower first appears, and buckling load and displacement considering the material and geometric nonlinearity reduce 52% and 58% compared with that only considering geometry nonlinearity. The linear and nonlinear buckling load of the wind power tower which is 90° sidewind are 1.8 and 1.2 times than those facing the wind direction.

The effects of cutouts on buckling behavior of composite plates

2012 ◽  
Vol 19 (3) ◽  
pp. 323-330 ◽  
Author(s):  
Ahmet Erkliğ ◽  
Eyüp Yeter
Keyword(s):  
Fiber Orientation ◽  
Polymer Matrix Composites ◽  
Orientation Angle ◽  
Composite Plates ◽  
Buckling Load ◽  
Matrix Composites ◽  
Element Analysis ◽  
Buckling Loads ◽  
Buckling Behavior ◽  
Fiber Orientation Angle

AbstractCutouts such as circular, rectangular, square, elliptical, and triangular shapes are generally used in composite plates as access ports for mechanical and electrical systems, for damage inspection, to serve as doors and windows, and sometimes to reduce the overall weight of the structure. This paper addresses the effects of different cutouts on the buckling behavior of plates made of polymer matrix composites. To study the effects of cutouts on buckling, loaded edges are taken as fixed and unloaded edges are taken as free. Finite element analysis is also performed to predict the effects of different geometrical cutouts, orientations, and position of cutouts on the buckling behavior. The results show that fiber orientation angle and cutout sizes are the most important parameters on the buckling loads. For all types of cutouts the buckling loads decrease dramatically by increasing the fiber orientation angle. It is observed that minimum buckling load is reached when 45° fiber angle is used, and after this angle critical buckling load begins to increase. Also, it is concluded that while fiber orientation angle is 0°, elliptical cutout has the highest buckling load and while fiber orientation angle is 45°, circular cutout has the highest buckling load.

Evaluation of mechanical and dynamic mechanical properties of multiwalled carbon nanotube-based ethylene–propylene copolymer composites mixed by masterbatch dilution

2016 ◽  
Vol 50 (29) ◽  
pp. 4093-4101 ◽  
Author(s):  
Maija Hoikkanen ◽  
Minna Poikelispää ◽  
Amit Das ◽  
Uta Reuter ◽  
Wilma Dierkes ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Aspect Ratio ◽  
Melt Mixing ◽  
Multiwalled Carbon ◽  
Mixing Processes ◽  
Ethylene Propylene ◽  
Dynamic Mechanical ◽  
Mixing Method

A two-step masterbatch mixing technique was studied for preparation of carbon nanotube-filled ethylene–propylene diene elastomer compounds, and compared to conventional one-step mixing process. In the two-step process, a masterbatch compound with carbon nanotube content of 50 parts per hundred was prepared by melt-mixing ethylene–propylene diene elastomer. This material was then compounded with pristine ethylene–propylene diene elastomer and composites with different carbon nanotube concentrations were compared. The aim of this study is to compare the efficiency of two different mixing processes on the dispersion of carbon nanotubes and to facilitate the handling of carbon nanotubes, as the masterbatch can be prepared in a controlled way and used for further dilution without the problems related to carbon nanotube processing. The compound properties were studied with emphasis on mechanical characterization and dynamic mechanical thermal analysis. Masterbatch mixing resulted in the similar mechanical properties of the composites compared to the direct mixing method. At the relatively low loadings of carbon nanotubes, the considerable improvements of the mechanical properties were observed. The aspect ratio of the carbon nanotubes determined by transmission electron microscope was found to be similar to the one calculated from the Guth equation. It showed a considerable reduction in aspect ratio independent of the used mixing method.

scholarly journals Buckling Behavior of Nanobeams Placed in Electromagnetic Field Using Shifted Chebyshev Polynomials-Based Rayleigh-Ritz Method

Nanomaterials ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 1326 ◽  
Author(s):  
Subrat Kumar Jena ◽  
Snehashish Chakraverty ◽  
Francesco Tornabene
Keyword(s):  
Boundary Condition ◽  
Closed Form ◽  
Chebyshev Polynomials ◽  
Ritz Method ◽  
Closed Form Solution ◽  
Form Solution ◽  
Buckling Load ◽  
Mode Shapes ◽  
Critical Buckling Load ◽  
Buckling Behavior

In the present investigation, the buckling behavior of Euler–Bernoulli nanobeam, which is placed in an electro-magnetic field, is investigated in the framework of Eringen’s nonlocal theory. Critical buckling load for all the classical boundary conditions such as “Pined–Pined (P-P), Clamped–Pined (C-P), Clamped–Clamped (C-C), and Clamped-Free (C-F)” are obtained using shifted Chebyshev polynomials-based Rayleigh-Ritz method. The main advantage of the shifted Chebyshev polynomials is that it does not make the system ill-conditioning with the higher number of terms in the approximation due to the orthogonality of the functions. Validation and convergence studies of the model have been carried out for different cases. Also, a closed-form solution has been obtained for the “Pined–Pined (P-P)” boundary condition using Navier’s technique, and the numerical results obtained for the “Pined–Pined (P-P)” boundary condition are validated with a closed-form solution. Further, the effects of various scaling parameters on the critical buckling load have been explored, and new results are presented as Figures and Tables. Finally, buckling mode shapes are also plotted to show the sensitiveness of the critical buckling load.

scholarly journals Model Progress for Tensile Power of Polymer Nanocomposites Reinforced with Carbon Nanotubes by Percolating Interphase Zone and Network Aspects

Polymers ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1047 ◽  
Author(s):  
Yasser Zare ◽  
Kyong Yop Rhee
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanotube ◽  
Aspect Ratio ◽  
Polymer Nanocomposites ◽  
Simple Simulation ◽  
Advanced Model

In the present work, a simple simulation is advanced based on a Callister equation considering the impacts of interphase and carbon nanotube (CNT) nets on the strength of nanocomposites after percolation onset. The advanced model can analyze the strength of nanocomposite by filler aspect ratio (α), percolation beginning ( φ p ), interphase depth (t), interphase power (σi), net density (N), and net power (σN). The empirical consequences of several samples agree with the estimations of the industrialised model. The nanocomposite strength straightly depends on “α”, “t”, “σi”, “N”, and “σN”, while the radius and percolation onset of CNT play the inverse characters. The reasonable impacts of net and interphase possessions on the nanocomposite strength rationalise the accurate progress of the Callister equation.

Sign in / Sign up

Export Citation Format

Share Document