eng
Shahid Chamran University of Ahvaz
Journal of Applied and Computational Mechanics
2383-4536
2383-4536
2016-08-01
2
3
128
133
10.22055/jacm.2016.12364
12364
مقاله پژوهشی
Free Vibration of Annular Plates by Discrete Singular Convolution and Differential Quadrature Methods
Kadir Mercan
mercankadir32@gmail.com
1
Hakan Ersoy
hakanersoy@akdeniz.edu.tr
2
Omer Civalek
civalek@yahoo.com
3
Akdeniz University Civil ENG.DEPT.
Akdeniz University Mechanical Engineering Dept.
Civil Engineering Dept.
Plates and shells are significant structural components in many engineering and industrial applications. In this study, the free vibration analysis of annular plates is investigated. To this aim, two different numerical methods including the differential quadrature and the discrete singular convolution methods are performedfor numerical simulations. Moreover, the Frequency values are obtained via these two methods and finally, the performance of these methods is investigated.
http://jacm.scu.ac.ir/article_12364_88f0f2fec3a098cf8da424a85eb4d15e.pdf
Differential quadrature
discrete singular convolution
annular plate
Free vibration
eng
Shahid Chamran University of Ahvaz
Journal of Applied and Computational Mechanics
2383-4536
2383-4536
2016-08-01
2
3
134
143
10.22055/jacm.2016.12453
12453
مقاله پژوهشی
Springbackward Phenomenon of a Transversely Isotropic Functionally Graded Composite Cylindrical Shell
V. R. Manthena
vkmanthena@gmail.com
1
N. K. Lamba
navneetkumarlamba@gmail.com
2
G. D. Kedar
gdkedar2013@gmail.com
3
Department of Mathematics, RTM Nagpur University, Nagpur, India.
Deptt. of Mathematics, Shri Lemdeo Patil Mahavidyalya, Nagpur, India.
Deptt. of Mathematics, RTM Nagpur University, Nagpur, India.
This study provides an approach to predict the springback phenomenon during post-solidification cooling in a functionally graded hybrid composite cylindrical shell with a transverse isotropic structure. Here, the material properties are given with a general parabolic power-law function. During the theoretical analysis, an appropriate transformation is introduced in the equilibrium equation, which is resulting in a hypergeometrical differential equation. Thermoelastic solutions are obtained and analyzed for a homogeneous, nonhomogeneous, and elastic-plastic state. The solution is validated by applying it to the multilayered functionally graded cylindrical shell using the transfer or propagator matrix method.
http://jacm.scu.ac.ir/article_12453_4f251b9e37e05534954578425bbf937f.pdf
Thermoelasticity
Functionally Graded Hybrid Composites
Cylindrical shell
Spring Backward Effect
eng
Shahid Chamran University of Ahvaz
Journal of Applied and Computational Mechanics
2383-4536
2383-4536
2016-08-01
2
3
144
151
10.22055/jacm.2016.12516
12516
مقاله پژوهشی
Conjugate and Directional Chaos Control Methods for Reliability Analysis of CNT–Reinforced Nanocomposite Beams under Buckling Forces; A Comparative Study
Behrooz Keshtegar
bkeshtegar@uoz.ac.ir
1
Zeng meng
mengz@hfut.edu.cn
2
University of Zabol
hefei university of technology
The efficiency and robustness of reliability methods are two important factors in the first-order reliability method (FORM). The conjugate choice control (CCC) and directional chaos control method (DCC) are developed to improve the robustness and efficiency of the FORM formula using the stability transformation method. In this paper, the CCC and DCC methods are applied for the reliability analysis of a nanocomposite beam as a complex engineering problem, which is reinforced by carbon nanotubes (CNTs) under buckling force. The probabilistic model for nanocomposite beam is developed through the buckling failure mode which is computed by using the Euler-Bernoulli beam model. The robustness and efficiency CCC and DCC are compared using the stable solution and a number of call limit state functions. The results demonstrate that the CCC method is more robust than the DCC in this case, while the DCC method is simpler than the CCC.
http://jacm.scu.ac.ir/article_12516_73ba1fbeb8bc9c72b9a4ab117f913bfc.pdf
Reliability analysis
Nanocomposite beam
Conjugate chaos control
Directional chaos control
eng
Shahid Chamran University of Ahvaz
Journal of Applied and Computational Mechanics
2383-4536
2383-4536
2016-08-01
2
3
152
173
10.22055/jacm.2016.12525
12525
مقاله پژوهشی
Generalized Warping In Flexural-Torsional Buckling Analysis of Composite Beams
Amalia Argyridi
a.argyridi@gmail.com
1
Evangelos Sapountzakis
cvsapoun@central.ntua.gr
2
Institute of Structural Analysis &amp; Aseismic Research
School of Civil Engineering
National Technical University of Athens
Zografou Campus
Athens 157 80, Greece
Institute of Structural Analysis & Aseismic Research School of Civil Engineering National Technical University of Athens Zografou Campus Athens 157 80, Greece
The finite element method is employed for the ﬂexural-torsional linear buckling analysis of beams of arbitrarily shaped composite cross-section taking into account generalized warping (shear lag effects due to both ﬂexure and torsion). The contacting materials, that constitute the composite cross section, may include a finite number of holes. A compressive axial load is applied to the beam. The influence of nonuniform warping is considered by the usage of one independent warping parameter for each warping type, i.e. shear warping in each direction and primary as well as secondary torsional warping, multiplied by the respective warping function. The calculation of the four aforementioned warping functions is implemented by the solution of a corresponding boundary value problem (longitudinal local equilibrium equation). The resulting stress field is corrected through a shear stress correction. The equations are formulated with reference to the independent warping parameters additionally to the displacement and rotation components.
http://jacm.scu.ac.ir/article_12525_cfcd6a2d7bf38582043a42498f071397.pdf
Nonuniform warping
Shear lag
Shear deformation
Composite beams
Flexural-torsional buckling
eng
Shahid Chamran University of Ahvaz
Journal of Applied and Computational Mechanics
2383-4536
2383-4536
2016-08-01
2
3
174
191
10.22055/jacm.2016.12515
12515
مقاله پژوهشی
Deformation Characteristics of Composite Structures
Theddeus T. AKANO
takano@unilag.edu.ng
1
Omotayo. A FAKINLEDE
oafak@unilag.edu.ng
2
Patrick Olayiwola
olayiwola_patrickshola@yahoo.com
3
Department of Systems Engineering, University of Lagos, NIGERIA
Department of Systems Engineering, University of Lagos, NIGERIA
Bells University of Technology
The composites provide design flexibility because many of them can be moulded into complex shapes. The carbon fibre-reinforced epoxy composites exhibit excellent fatigue tolerance and high specific strength and stiffness which have led to numerous advanced applications ranging from the military and civil aircraft structures to the consumer products. However, the modelling of the beams undergoing the arbitrarily large displacements and rotations, but small strains, is a common problem in the application of these engineering composite systems. This paper presents a nonlinear finite element model which is able to estimate the deformations of the fibre-reinforced epoxy composite beams. The governing equations are based on the Euler-Bernoulli beam theory (EBBT) with a von Kármán type of kinematic nonlinearity. The anisotropic elasticity is employed for the material model of the composite material. Moreover, the characterization of the mechanical properties of the composite material is achieved through a tensile test, while a simple laboratory experiment is used to validate the model. The results reveal that the composite fibre orientation, the type of applied load and boundary condition, affect the deformation characteristics of the composite structures. The nonlinearity is an important factor that should be taken into consideration in the analysis of the fibre-reinforced epoxy composites.
http://jacm.scu.ac.ir/article_12515_012626b5b1aa42624b3e4979ade796c5.pdf
Anisotropic elasticity
composite material
large displacement
eng
Shahid Chamran University of Ahvaz
Journal of Applied and Computational Mechanics
2383-4536
2383-4536
2016-08-01
2
3
192
199
10.22055/jacm.2016.12526
12526
مقاله پژوهشی
Modified Rectangular Patch Antenna Loaded With Multiple C Slots for Multiple Applications
Amit Jain
jain.2102@gmail.com
1
Monika Surana
suranamonika@gmail.com
2
Poorima College of Engineering, Jaipur, Rajasthan, India
Poorima College of Engineering, Jaipur, Rajasthan, India
A new multiple C-slotted microstrip patch antenna is proposed in the present study. A patch antenna is a wide-beam narrowband antenna. The microstrip patch antenna consists of a very thin metallic strip (patch) placed a small fraction of a wavelength above a ground plane. The patch can be designed in any possible shape and normally made of conducting materials such as copper or gold. This study presents a design of a C-Slotted microstrip patch antenna for multiple applications. The proposed antenna's characteristics include a low cost, easy fabrication and good isolation along with Quad different frequency bands which are centered at 1.60 GHz, 2.50 GHz, 4.70 GHz and 5.50 GHz for parameter S11. The antenna is designed, simulated, and optimized for Quad band performance by using IE3D software. The C-shape-slotted patch antenna is designed on a FR4 substrate with the thickness of 1.59 mm and the relative permittivity of 4.4. The proposed patch dimension is 16*16 mm and it utilizes the microstrip line feed. The simulated results parameter S11 and S12, shows that the antenna can cover the bands of several applications including GPS (1.2-1.6 GHz), GSM (1.8-1.9 GHz) and WiMAX (2.3-5.8 GHz). Simulation results are presented in terms of Resonant Frequency, Return Loss, Voltage Standing Wave Ratio (VSWR) and Radiation Pattern.
http://jacm.scu.ac.ir/article_12526_05757c3e6ba8ad3459696bbf7348aece.pdf
Microstrip antenna
Slotted patch
GPS
GSM
WiMAX