Comparison of the application of smart electrorheological and magnetorheological fluid cores to damp sandwich panels’ vibration behavior, based on a novel higher-order shear deformation theory

2021 ◽  
pp. 095440892110378
Author(s):  
Mehdi Keshavarzian ◽  
Mohammad M Najafizadeh ◽  
Korosh Khorshidi ◽  
Peyman Yousefi ◽  
Seyed Majid Alavi
Keyword(s):  
Electric Fields ◽  
Natural Frequencies ◽  
Sandwich Panels ◽  
Shear Deformation Theory ◽  
Magnetorheological Fluid ◽  
Order Theory ◽  
Higher Order ◽  
Lower Sensitivity ◽  
Inertia Effects ◽  
Vibration Behavior

Background: Magnetorheological and electrorheological materials show variations in their rheological properties when subjected to magnetic and electric fields. We analyzed the vibration control behavior of a sandwich panel with elastic face sheets and an electrorheological or magnetorheological fluid core, using an improved higher-order theory. The theory was applied to the analysis of the structure's components as a combination of exponential, trigonometric, and polynomial functions. The core's flexibility was analyzed based on Frostig's second model, which has attracted material science researchers’ attention. Methods: Using the new theory, we analyzed the transverse shear and rotary inertia effects of the cover sheets. The governing equations and boundary conditions were derived by Hamilton's principle. The natural frequencies and loss factors were derived by solving the eigenvalue problem. The effects of changing the geometric parameters, the thickness of the magnetorheological or electrorheological layer, and thickness ratios on the vibration behavior of the panel were determined. Results: The panel's natural frequencies increased when the magnetic or electric field strength, and the panel's aspect ratio increased. It decreased when the core to panel thickness ratio increased. The magnetorheological material showed higher strength and lower sensitivity to external impurities than did the electrorheological material. Conclusions: We conclude that the magnetorheological materials minimize the structure's vibration at high-frequency operation, and the electrorheological materials are optimal for minimizing the structure's vibration at lower frequency operation. The findings of this study are useful to better understand the vibration behavior of sandwich panels with laminates under free vibration conditions.

A Simple Higher-Order Theory for Laminated Composite Plates

1984 ◽  
Vol 51 (4) ◽  
pp. 745-752 ◽  
Author(s):  
J. N. Reddy
Keyword(s):  
Shear Deformation ◽  
Deformation Theory ◽  
Shear Deformation Theory ◽  
Laminated Composite ◽  
Composite Plates ◽  
Order Theory ◽  
Higher Order ◽  
Laminated Composite Plates ◽  
First Order ◽  
First Order Theory

A higher-order shear deformation theory of laminated composite plates is developed. The theory contains the same dependent unknowns as in the first-order shear deformation theory of Whitney and Pagano [6], but accounts for parabolic distribution of the transverse shear strains through the thickness of the plate. Exact closed-form solutions of symmetric cross-ply laminates are obtained and the results are compared with three-dimensional elasticity solutions and first-order shear deformation theory solutions. The present theory predicts the deflections and stresses more accurately when compared to the first-order theory.

Analysis of damped composite sandwich plates using plate bending elements with substitute shear strain fields based on Reddy's higher-order theory

2002 ◽  
Vol 216 (5) ◽  
pp. 591-606 ◽  
Author(s):  
A K Nayak ◽  
R A Shenoi ◽  
S S J Moy
Keyword(s):  
Natural Frequencies ◽  
Mass Matrix ◽  
Order Theory ◽  
Higher Order ◽  
Sandwich Plates ◽  
Assumed Strain ◽  
Parametric Effects ◽  
Higher Order Theory ◽  
Damping Materials ◽  
Loss Factors

Two new C0 assumed strain finite element formulations of Reddy's higher-order theory are used to determine the natural frequencies and loss factors of layered anisotropic composite and sandwich plates. Material properties typical of fibre polyester resins for the skin and HEREX C70 PVC foam damping materials for cores are used to show the parametric effects of plate aspect ratio, length-thickness ratio on natural frequencies and loss factors. A consistent mass matrix is adopted in the present formulation. Both frequency-independent and frequency-dependent damping of viscoelastic materials are considered. The developed elements are free from spurious zero energy modes due to the assumed strain approach.

A two-variable simplified nth-higher-order theory for free vibration behavior of laminated plates

2017 ◽  
Vol 182 ◽  
pp. 533-541 ◽  
Author(s):  
Mokhtar Bouazza ◽  
Yamina Kenouza ◽  
Noureddine Benseddiq ◽  
Ashraf M. Zenkour
Keyword(s):  
Free Vibration ◽  
Order Theory ◽  
Higher Order ◽  
Laminated Plates ◽  
Vibration Behavior ◽  
Higher Order Theory

Buckling behaviour of cross-ply laminated plates by a higher-order shear deformation theory

2012 ◽  
Vol 19 (2) ◽  
pp. 119-125 ◽  
Author(s):  
Ana M.A. Neves ◽  
António J.M. Ferreira ◽  
Erasmo Carrera ◽  
Maria Cinefra ◽  
Carla M.C. Roque ◽  
...  
Keyword(s):  
Deformation Theory ◽  
Shear Deformation Theory ◽  
Order Theory ◽  
Higher Order ◽  
Laminated Plates ◽  
Basis Functions ◽  
Governing Equations ◽  
Collocation Technique ◽  
Radial Basis ◽  
Higher Order Theory

AbstractIn this article, Carrera’s Unified Formulation (CUF) is combined with a radial basis function collocation technique. A higher-order theory that considers deformations in the thickness direction was developed under CUF to predict the buckling behaviour of laminated plates. The obtained governing equations and boundary conditions are then interpolated by collocation with radial basis functions. The accuracy and efficiency of the combination of the two techniques for buckling problems of laminated plates are demonstrated through numerical experiments.

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

2021 ◽  
pp. 146442072199941
Author(s):  
Tripuresh Deb Singha ◽  
Tanmoy Bandyopadhyay ◽  
Amit Karmakar
Keyword(s):  
Carbon Nanotube ◽  
Free Vibration ◽  
Shear Deformation ◽  
Conical Shell ◽  
Deformation Theory ◽  
Natural Frequencies ◽  
Shear Deformation Theory ◽  
Higher Order ◽  
Functionally Graded ◽  
Reinforced Composite

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.

A Higher-Order Theory for Vibration of Doubly Curved Shallow Shells

1996 ◽  
Vol 63 (3) ◽  
pp. 587-593 ◽  
Author(s):  
K. M. Liew ◽  
C. W. Lim
Keyword(s):  
Transverse Shear ◽  
Shear Deformation Theory ◽  
Order Theory ◽  
Higher Order ◽  
Shallow Shells ◽  
Shear Distribution ◽  
Strain Components ◽  
Shear Strains ◽  
Doubly Curved ◽  
Transverse Shear Strains

A higher-order shear deformation theory is presented for vibration analysis of thick, doubly curved shallow shells. An orthogonal curvilinear coordinate system is employed to arrive at the strain components. A third-order displacement field in transverse coordinate is adopted. Though no transverse normal stress is assumed, the theory accounts for cubic distribution of the transverse shear strains through the shell thickness in contrast with existing parabolic shear distribution. The unsymmetric shear distribution is a physical consequence of the presence of shell curvatures where the stress and strain of a point above the mid-surface are different from its counterpart below the mid-surface. Imposing the vanishing of transverse shear strains on top and bottom surfaces, the rotation field is reduced from a six-degree to a two-degree system. The discrepancy between the existing and the present theories is highlighted.

On the flexural and vibration behavior of imperfection sensitive higher order functionally graded material skew sandwich plates in thermal environment

2018 ◽  
Vol 233 (4) ◽  
pp. 1271-1288 ◽  
Author(s):  
Sanjay Singh Tomar ◽  
Mohammad Talha
Keyword(s):  
Functionally Graded Material ◽  
Volume Fraction ◽  
Thermal Environment ◽  
Shear Deformation Theory ◽  
Higher Order ◽  
Functionally Graded ◽  
Sandwich Plates ◽  
Skew Angle ◽  
Vibration Behavior ◽  
Graded Material

This work presents an investigation on the flexural and vibration behavior of imperfection sensitive higher order functionally graded material skew sandwich plates in thermal environment. Material properties have been assumed to be temperature dependent and graded in transverse direction following the power law distribution. Reddy’s higher order shear deformation theory has been used to model displacement field kinematics of skew sandwich plate. Variational principle has been used for deriving the governing equations. Finite element methodology has been adopted to discretize plate domain. Convergence and comparison studies have been performed to demonstrate the reliability of present formulation. Effect of various system parameters such as thickness ratio, volume fraction index, skew angle, imperfection parameter, and boundary conditions on the flexural and vibration response have been investigated.

A Higher Order Theory for Bending of Cross Ply Laminated Cylindrical Shell under Hygrothermal Loads

2015 ◽  
Vol 1115 ◽  
pp. 509-512 ◽  
Author(s):  
J.S. Mohamed Ali ◽  
Saleh Alsubari ◽  
Yulfian Aminanda
Keyword(s):  
Shear Deformation ◽  
Deformation Theory ◽  
Shear Deformation Theory ◽  
Order Theory ◽  
Higher Order ◽  
Graphical Form ◽  
Laminated Shells ◽  
Elasticity Solutions ◽  
3D Elasticity ◽  
Higher Order Theory

The combined effect of moisture and temperature on the bending behaviour of simply supported cross ply composite laminated shells has been investigated. A 13 term accurate higher order shear deformation theory with zigzag function is used in this analysis in which the effects of transverse shear deformation are taken into account. The results are presented for thermal load cases are validated against available 3D elasticity solutions in the literature and useful results for combined hygrothermal loading are presented in tabular and graphical form.

Sign in / Sign up

Export Citation Format

Share Document