Ponnusamy P.,Government Arts College Autonomous
Multidiscipline Modeling in Materials and Structures | Year: 2013
Purpose - This paper aims to describe the method for solving vibration problem of electro-magneto-elastic plate of polygonal (triangle, square, pentagon and hexagon) cross-sections using Fourier expansion collocation method (FECM). Design/methodology/approach - A mathematical model is developed to study the wave propagation in an electro-magneto-elastic plate of polygonal cross-sections using the theory of elasticity. The frequency equations are obtained from the arbitrary cross-sectional boundary conditions, since the boundary is irregular in shape; it is difficult to satisfy the boundary conditions along the surface of the plate directly. Hence, the FECM is applied along the boundary to satisfy the boundary conditions. The roots of the frequency equations are obtained by using the secant method, applicable for complex roots. Findings - From the literature survey, it is clear that the free vibration of electro-magneto-elastic plate of polygonal cross-sections have not been analyzed by any of the researchers, also the previous investigations in the vibration problems of electro-magneto-elastic plates are based on the traditional circular cross-sections only. So, in this paper, the wave propagation in electro-magneto-elastic plate of polygonal cross-sections is studied using the FECM. The computed non-dimensional frequencies are plotted in the form of dispersion curves and their characteristics are discussed. Originality/value - The researchers have discussed the circular, rectangular, triangular and square cross-sectional plates by the boundary conditions. In this problem, the author studied the vibrations of polygonal (triangle, square, pentagon and hexagon) cross-sectional plates using the geometrical relation which is applicable to all the cross-sections. The problem may be extended to any kinds of cross-sections by using the proper geometrical relations. © Copyright - 2013 Emerald Group Publishing Limited. All rights reserved.
Ponnusamy P.,Government Arts College Autonomous
Multidiscipline Modeling in Materials and Structures | Year: 2011
Purpose The purpose of this paper is to study the wave propagation in a homogeneous isotropic, thermo-elastic plate of arbitrary cross-sections using the two-dimensional theory of thermo-elasticity. Design/methodology/approach A mathematical model is developed to study the wave propagation in an arbitrary cross-sectional thermo-elastic plate by using two-dimensional theory of thermo-elasticity. After developing the formal solution of the mathematical model consisting of partial differential equations, the frequency equations have been derived by using the boundary conditions prevailing at the arbitrary cross-sectional surface of the plate for symmetric and antisymmetrical modes in completely separate forms using Fourier expansion collocation method. The roots of the frequency equation are obtained by using the secant method, applicable for complex roots. Findings The computed non-dimensional frequencies are compared with those results available in the literature in the case of elliptic cross-sectional solid plate with clamped edges without thermal field and this result is coincide with the results of Nagaya. The computed non-dimensional frequencies are plotted in the form of dispersion curves for longitudinal and flexural (symmetric and antisymmetric) modes of vibrations for the material copper. Originality/value The wave propagation in a plate of arbitrary cross-sections with the stress free (unclamped) and rigidly fixed (clamped) edges are analyzed with and without thermal field. © Copyright - 2011 Emerald Group Publishing Limited. All rights reserved.
Raja C.R.,Government Arts College Autonomous |
Joseph A.A.,St. Josephs College
Materials Letters | Year: 2010
An organic nonlinear optical material, l-valinium fumarate (abbreviated as LVF) has been successfully synthesized and good quality single crystals have been grown by low temperature solution growth method. The purified form of LVF is achieved by repeated crystallization. The cell parameters of LVF have been determined using single crystal X-ray diffraction technique and the crystal system is found as monoclinic. From the UV-Vis-NIR absorption spectrum, the good transparency is revealed from 300 nm to 1100 nm. The mode of vibration of different molecular groups present in LVF was identified by FT-IR spectral analysis. The thermogravimetric (TGA) and differential thermal analysis (DTA) studies show the thermal behavior and crystal was thermally stable up to 266 °C. Second harmonic generation (SHG) conversion test was made to explore the nonlinear optical behavior of this material using Kurtz and Perry method. © 2009 Elsevier B.V. All rights reserved.
Mahalakshmi G.,Karpagam University |
Mahalakshmi G.,Government Arts College Autonomous |
Balachandran V.,Arignar Anna Government Arts College
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2014
The FT-IR and FT-Raman spectra of 4-Aminomethylpiperidine have been recorded using Perkin Elmer Spectrophotometer and Nexus 670 spectrophotometer. The equilibrium geometrical parameters, various bonding features, the vibrational wavenumbers, the infrared intensities and the Raman scattering activities were calculated using Hartree-Fock and density functional method (B3LYP) with 6-311+G(d,p) basis set. Detailed interpretations of the vibrational spectra have been carried out with the aid of the normal coordinate analysis. The spectroscopic and natural bonds orbital (NBO) analysis confirms the occurrence of intra molecular hydrogen bonds, electron delocalization and steric effects. The changes in electron density in the global minimum and in the energy of hyperconjugative interactions of 4-Aminomethylpiperidine (4AMP) were calculated. The theoretical UV-Visible spectrum of the compound was computed in the region 200-400 nm by time-dependent TD-DFT approach. The calculated HOMO and LUMO energies show that charge transfer occur within the molecule. The dipole moment (μ) and polarizability (α), anisotropy polarizability (Δα) and hyperpolarizability (β) of the molecule have been reported. © 2014 Elsevier B.V. All rights reserved.
Ponnusamy P.,Government Arts College Autonomous |
Selvamani R.,Karunya University
European Journal of Mechanics, A/Solids | Year: 2013
This work investigates the three dimensional wave propagation of a homogeneous transversely isotropic magneto thermo elastic cylindrical panel in the context of the linear theory of thermo elasticity. Three displacement potential functions are introduced to uncouple the equations of motion. A Bessel function solution with complex arguments is directly used to analyze the frequency equations with traction-free boundary conditions. The special cases have also been deduced for magneto elastic, thermo elastic and elastokinetic at various levels from the present analysis. The numerical example which demonstrates the present method is studied for the material magnetostrictive cobalt iron oxide (CoFe2O4). The computed non-dimensional phase velocity and attenuation coefficient are plotted in the form of dispersion curves. The coupling effect among thermal, magnetic and elastic in magneto thermo elastic material provides a mechanism for sensing thermo mechanical disturbances in the design of sensors and surface acoustic damping filters. © 2012 Elsevier Masson SAS. All rights reserved.