Faculty Publications

Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736

Publications by NITK Faculty

Browse

Subject: search.filters.subject.Grading

Search Results

Now showing 1 - 10 of 24
  • No Thumbnail Available
    Item
    Buckling and free vibration of nonuniformly heated functionally graded carbon nanotube reinforced polymer composite plate
    (World Scientific Publishing Co. Pte Ltd wspc@wspc.com.sg, 2017) George, N.; Jeyaraj, P.; Murigendrappa, S.M.
    Buckling and free vibration behavior of functionally graded carbon nanotube reinforced polymer composite plate subjected to nonuniform temperature fields have been investigated using finite element approach. The effective material constants of the plate are obtained using the extended rule of mixture along with efficiency parameters of the carbon nanotube (to include geometry-dependent material properties). Influence of boundary conditions, aspect ratio, functional grading of the carbon nanotube, nonuniform thermal loading on thermal buckling and free vibration behavior of the heated plate are analyzed. It is observed that temperature fields and functional grading are influenced on the critical buckling temperature of the plates. Further, nature of functional grading showed significant change in buckling mode shapes irrespective of the boundary conditions. The first few natural frequencies of the plate under thermal load decreases as the temperature increases and they are influenced significantly by the nature of temperature field. Variations in free vibration mode shapes of the square plates found with not significant change as temperature increases. However, free vibration modes of the rectangular plates are sensitive to the nature of temperature field whenever there is a free edge associated with the boundary condition. Influence of functional grading on the free vibration mode shapes is not significant in contrast with the free vibration natural frequencies. The magnitude of free vibration natural frequencies of functional grade-X type carbon nanotube reinforcement showed higher in comparison with other two types of reinforcements considered here. © 2017 World Scientific Publishing Company.
  • No Thumbnail Available
    Item
    Free vibration and static analysis of functionally graded skew magneto-electro-elastic plate
    (Techno-Press, 2018) Kiran, M.C.; Kattimani, S.
    This article presents a finite element (FE) model to assess the free vibration and static response of a functionally graded skew magneto-electro-elastic (FGSMEE) plate. Through the thickness material grading of FGSMEE plate is achieved using power law distribution. The coupled constitutive equations along with the total potential energy approach are used to develop the FE model of FGSMEE plate. The transformation matrix is utilized in bringing out the element matrix corresponding to the global axis to a local axis along the skew edges to specify proper boundary conditions. The effect of skew angle on the natural frequency of an FGSMEE plate is analysed. Further, the study includes the evaluation of the static behavior of FGSMEEplate for various skew angles.The influence of skew angle on the primary quantities such as displacements, electric potential, and magnetic potential, and secondary quantities such as stresses, electric displacement and magnetic induction is studied indetail. In addition, the effect of power-law gradient, thickness ratio, boundary conditions and aspect ratio on the free vibration and static response characteristics of FGSMEE plate has been investigated. © 2018 Techno-Press, Ltd.
  • No Thumbnail Available
    Item
    Vibro-acoustic behavior of functionally graded carbon nanotube reinforced polymer nanocomposite plates
    (SAGE Publications Ltd info@sagepub.co.uk, 2018) George, N.; Jeyaraj, P.; Murigendrappa, S.M.; Mailan Chinnapandi, M.C.
    This paper presents the numerical investigation results carried out on vibro-acoustic behavior of functionally graded carbon nanotube reinforced polymer nanocomposite plate using combined finite element method and Rayleigh integral. Parameter studies are carried out to analyze the in?uence of nature of functional grading, loading of carbon nanotube, and structural boundary conditions on free and forced vibration and sound radiation characteristics in detail. It is found that natural frequencies are significantly in?uenced by the nature of functional grading while the mode shapes are insensitive. The resonant amplitude of vibration and acoustic response are significantly in?uenced with the nature of different functional grading. This re?ects in the bandwise calculation of sound power also which recommends the carbon nanotube functional grading with X distribution along the thickness direction for lower frequency level. Similar variation in vibro-acoustic response has been observed with increase in the carbon nanotube loading also. © 2016, IMechE 2016.
  • No Thumbnail Available
    Item
    Analytical investigation on free vibration frequencies of polymer nano composite plate: Effect of graphene grading and non-uniform edge loading
    (Elsevier Ltd, 2020) Gunasekaran, V.; Jeyaraj, J.; Mailan Chinnapandi, L.B.M.
    An analytical investigation carried out on free vibration characteristics of functionally graded graphene reinforced nanocomposite (FG-GRC) plate under different non-uniform edge loads is presented. Graphene nano-platelets (GPLs) are homogeneously dispersed and graded by varying weight fraction through the thickness. An analytical method based on strain energy approach is adopted to estimate the buckling load. Natural frequencies of the FG-GRC plate are attained using analytical solutions derived based on Reddy's third-order shear deformation theorem (TDST). Results revealed that buckling and free vibration behavior of the plate is influenced by the GPLs dispersion pattern and weight fraction under non-uniform edge loads. It is also observed that buckling mode and the fundamental vibration mode of the plate under combined tensile-compression load is entirely different from the other non-uniform edge load cases. © 2020 Elsevier Ltd
  • No Thumbnail Available
    Item
    Free vibration and stability of graphene platelet reinforced porous nano-composite cylindrical panel: Influence of grading, porosity and non-uniform edge loads
    (Elsevier Ltd, 2021) Twinkle, T.; Jeyaraj, J.
    Buckling and vibration characteristics of functionally graded(FG) porous(P), graphene platelet (GPL) reinforced cylindrical panel are presented. A multilayer model is considered for analysis with graphene and internal pores distribution varying in an uniformly or two different non-uniformly manner along the thickness. To evaluate the effective mechanical properties, extended rule of mixture together with modified Halpin-Tsai micromechanics model and mechanical properties of open-cell metal foams is used. Considering a higher order shear deformation theory, characteristics of the FG-P-GPL reinforced cylindrical panel under different edge loads such as uniform, triangular, trapezoidal and parabolic are investigated. The Hamilton's principle is used to formulate the governing partial differential equations and buckling and free vibration solutions are obtained by employing the Galerkins method. The influences of grading of GPL and internal pores, porosity coefficient on buckling and dynamic characteristics of functionally graded GPL reinforced porous cylindrical panel under uniform and non-uniform in-plane loads are presented. © 2020 Elsevier Ltd
  • No Thumbnail Available
    Item
    Analytical Solution for Sound Radiation Characteristics of Graphene Nanocomposites Plate: Effect of Porosity and Variable Edge Load
    (World Scientific, 2021) Gunasekaran, V.; Jeyaraj, J.; Mailan Chinnapandi, L.B.; Kumar, A.
    The effects of graded dispersion of graphene platelets and porosity on vibro-acoustics of nanocomposite plate exposed to variable edge loads are analytically investigated. Voigt and Halpin-Tsai micromechanics model is used to obtain effective properties of the porous graphene nanocomposites. The strain energy technique is implemented to estimate the buckling load (Pcr). By means of Reddy's third-order shear deformation theorem and Rayleigh Integral, vibration and acoustic responses are obtained. After validating the present analysis with the published results, the nature of edge loads on buckling and vibro-acoustic response is significant. It is noted that an increase in the intensity of non-uniform in-plane loads leads to changes in free vibration modes and resonant amplitude of response. The weight percentage and grading pattern of graphene reinforcement cause the stiffness hardening effect, whereas porosity distribution and coefficients cause the stiffness softening effect on the nanocomposite plate. It is found that the plate with symmetric distribution of graphene platelets with more concentration at the surface and symmetric porosity variation with more porosity at the center radiates less sound power. © 2021 World Scientific Publishing Company.
  • No Thumbnail Available
    Item
    Buckling and Free Vibration of Porous Functionally Graded Metal Ceramic Beams under Thermal and Mechanical Loading: A Comparative Study
    (Springer, 2021) Patil, H.B.; Jeyaraj, J.; Mailan Chinnapandi, L.B.
    Buckling and free vibration characteristics of functionally graded porous metal ceramic beams subjected to mechanical and thermal loads are presented. Five-noded, beam element with ten degrees of freedom is used to analyse the buckling and vibration behaviour. The effects of porosity, porosity pattern, functional grading of material, elastic foundations, slenderness ratio and different boundary conditions are analysed for critical comparison of behaviour of the beam under thermal and mechanical load. Results revealed that buckling and dynamic behaviour of the beam under thermal load is significantly different compared to the mechanical load. It is also observed that nature of porosity distribution and its volume fraction also influences the buckling strength significantly. Beam with uniform porosity shows better thermal buckling strength likewise beam with graded porosity for mechanical buckling strength. © 2021, The Institution of Engineers (India).
  • No Thumbnail Available
    Item
    Influence of porosity distribution on nonlinear free vibration and transient responses of porous functionally graded skew plates
    (China Ordnance Industry Corporation, 2021) Kumar H S, N.; Kattimani, S.; Nguyen, T.
    This article deals with the investigation of the effects of porosity distributions on nonlinear free vibration and transient analysis of porous functionally graded skew (PFGS) plates. The effective material properties of the PFGS plates are obtained from the modified power-law equations in which gradation varies through the thickness of the PFGS plate. A nonlinear finite element (FE) formulation for the overall PFGS plate is derived by adopting first-order shear deformation theory (FSDT) in conjunction with von Karman's nonlinear strain displacement relations. The governing equations of the PFGS plate are derived using the principle of virtual work. The direct iterative method and Newmark's integration technique are espoused to solve nonlinear mathematical relations. The influences of the porosity distributions and porosity parameter indices on the nonlinear frequency responses of the PFGS plate for different skew angles are studied in various parameters. The effects of volume fraction grading index and skew angle on the plate's nonlinear dynamic responses for various porosity distributions are illustrated in detail. © 2021 The Authors
  • No Thumbnail Available
    Item
    Sound absorption and transmission loss characteristics of 3D printed bio-degradable material with graded spherical perforations
    (Elsevier Ltd, 2022) Sailesh, R.; Yuvaraj, L.; Doddamani, M.; Mailan Chinnapandi, L.B.M.; Jeyaraj, J.
    The influence of spherical bubble perforations and their grading on acoustic characteristics of a 3D printed bio-degradable material is investigated. Samples with spherical bubble perforations of different sizes are distributed either uniformly or graded across the specimen thickness. A sample having typical cylindrical perforations is also analyzed for comparative analysis. Sound absorption (SA) and sound transmission loss (STL) characteristics are estimated by the impedance tube method. The results reveal that the SA of all functionally graded (FG) perforations is higher at low frequencies. The SA and bandwidth are higher for a specimen with uniform, lower diameter bubbles at higher frequencies. The STL of FG perforations is highest among the specimens, and the difference increases significantly with frequency. The numerical and experimental results match a high degree of accuracy. FG perforations exhibited superior performance for both SA and STL. The proposed graded spherical porosity can be effectively utilized in soundproofing applications across building and transportation sectors. © 2021 Elsevier Ltd
  • No Thumbnail Available
    Item
    Nonlinear analysis of two-directional functionally graded doubly curved panels with porosities
    (Techno-Press, 2022) Naveen Kumar, H.S.; Kattimani, S.
    This article investigates the nonlinear behavior of two-directional functionally graded materials (TDFGM) doubly curved panels with porosities for the first time. An improved and effectual approach is established based on the improved first-order shear deformation shell theory (IFSDST) and von Karman’s type nonlinearity. The IFSDST considers the effects of shear deformation without the need for a shear correction factor. The composition of TDFGM constitutes four different materials, and the modified power-law function is employed to vary the material properties continuously in both thickness and longitudinal directions. A nonlinear finite element method in conjunction with Hamilton’s principle is used to obtain the governing equations. Then, the direct iterative method is incorporated to accomplish the numerical results using the frequency-amplitude, nonlinear central deflection relations. Finally, the influence of volume fraction grading indices, porosity distributions, porosity volume, curvature ratio, thickness ratio, and aspect ratio provides a thorough insight into the linear and nonlinear responses of the porous curved panels. Meanwhile, this study emphasizes the influence of the volume fraction gradation profiles in conjunction with the various material and geometrical parameters on the linear frequency, nonlinear frequency, and deflection of the TDFGM porous shells. The numerical analysis reveals that the frequencies and nonlinear deformations can be significantly regulated by changing the volume fraction gradation profiles in a specified direction with an appropriate combination of materials. Hence, TDFGM panels can overcome the drawbacks of the functionally graded materials with a gradation of properties in a single direction. © © 2022 Techno-Press, Ltd.