Browsing by Author "Kattimani, S."

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A CFD-Based Design of S-Shaped Nozzle Attachment for Aircraft Cabin Gaspers
(Taylor and Francis Ltd., 2023) Srinivasa, V.K.; Kattimani, S.; Ganga Reddy, C.; Kavya, S.
Cough has been the primary mode for transmitting airborne respiratory diseases as the droplets expelled are suspended in the air longer in closed environments like aircraft cabins. Air jets from personal gasper nozzles are studied using computational fluid dynamics (CFD) simulations to understand the flow pattern, which is of high velocity, very narrow, and susceptible to enhanced air mixing. An S-shaped nozzle attachment uses higher-order Bezier curves to spread the flow across the passenger’s face to form a shield to protect the breathing zone from foreign particles. The design of experiments theory, the Box–Behnken design, was employed to understand the influence of nozzle profile geometric parameters on the output criteria through CFD simulations. The numerical simulations were performed on the final design, which shows that the newly designed nozzle attachment can distribute the narrow jet from existing personal gasper nozzles into a curved air curtain across the passenger’s face. © 2024 Informa UK Limited, trading as Taylor & Francis Group.
Active layer damping of bi-directionally tapered functionally graded sandwich plates with 1-3 piezoelectric composites
(Taylor and Francis Ltd., 2024) Shada, S.K.; Kattimani, S.; M.r, R.
This article investigates the effect of smart damping on bi-directionally tapered functionally graded sandwich plates. The substrate comprises FG material on both sides of the core of either soft herex or ceramic material. The viscoelastic layer of ALD is restrained, while the compelling layer consists of 1-3PZC. The finite element formulation developed incorporates layer-wise and first-order-shear-deformation theory. The plate’s damping is actively controlled using velocity feedback control incorporating piezoelectric patches. The effects of various parameters of taper ratio and patch positions on vibration control are investigated. The efficacy of the ALD in improving the structural performance of plates is investigated. © 2024 Taylor & Francis Group, LLC.
Active Vibration Control of Laminated Composite Beam Operating in Thermal Environment using PZT-5H Patches
(Semnan University, Faculty of Mechanical Engineering, 2022) Saini, K.; Ravi Kiran, A.; Kallannavar, V.; Kattimani, S.
This paper investigates the influence of temperature on the active vibration control of laminated composite cantilever beams using collocative experimental and simulation techniques. The system identification toolbox of the MATLAB simulation tool is utilized to obtain the transfer function of the plant model. The adequate vibration attenuation of the glass-epoxy cantilever beam operating in various thermal environments is achieved using the proportional (P) and proportional-integral-derivative (PID) controllers. The vibration attenuation characteristics of the developed control algorithms are comprehensively investigated for a wide temperature range of –20 °C to 60 °C using PZT-5H patches. Particular emphasis is given to the vibration control of the fundamental natural frequency of the laminated composite cantilever beam. The obtained results of open and closed-loop models are presented in both time and frequency domains. The results indicate that for all the temperatures considered, the PID controller is found to be more effective in vibration attenuation than the P controller. The vibration attenuation performance of the cantilever beam considerably improved at the higher magnitude of temperature values. The natural frequency of the system is reduced continuously with an increase in temperature. © 2022 Published by Semnan University Press. All rights reserved.
Aerostructural performance improvement in an unmanned long endurance aircraft using adaptive wing concept
(SAGE Publications Ltd, 2023) Sampath, A.K.; Padmanabhan, M.A.; Kattimani, S.
This paper presents an analytical research study to improve the aerostructural performance of an unmanned medium altitude long endurance aircraft using the adaptive wing concept. Aerodynamic drag and wing root loads are minimized by optimal scheduling of multiple trailing edge flaps located on the wing. A trim optimization process is developed specifically for this purpose. The aeroelastic model is based on finite element formulation for the structure and doublet lattice method for the aerodynamics. A nonlinear numerical lifting line method is used, in combination with airfoil wind tunnel data, to estimate the induced and total drags. Results are presented for the current aircraft configuration and a more flexible proposed configuration, thereby providing an uncommon perspective on the effect of flexibility on the adaptive wing. For example, the benefits of optimal flap deployment turn out to be greater for the flexible aircraft than for the rigid one. It is hoped that this work and its insights will also aid the multidisciplinary design optimization of future aircraft. © IMechE 2023.
An electromechanical coupling isogeometric approach using zig-zag function for modeling and smart damping control of multilayer PFG-GPRC plates
(Springer, 2024) Nguyen, T.; Ly, D.-K.; Kattimani, S.; Thongchom, C.
In this article, a novel numerical approach based on electromechanical coupling isogeometric analysis employing a piecewise linear zig-zag function is proposed for modeling and analysis of smart constrained layer damping (SCLD) treatment in multilayer porous functionally graded graphene platelets-reinforced composite (PFG-GPRC) plates. The approach efficiently approximates the geometric, mechanical, and electric displacement fields by utilizing non-uniform rational B-splines (NURBS) basis functions. These basis functions are subsequently integrated with the zig-zag formulation to characterize the system dynamic and help handle both continuous/discontinuous material properties at all interfaces, as well as improve the effectiveness of global–local numerical solutions for the analysis of current structures. The multilayer PFG-GPRC plate model is designed to incorporate porous, uniformly, or non-uniformly distributed layers based on three different graphene platelet patterns. The analysis of the SCLD treatment encompasses an examination of the frequency response function of the damped structure under passive/hybrid mechanisms, taking into account viscoelastic behavior and the converse piezoelectric effect. Reliability in the current analysis is demonstrated through a validation study, and a comprehensive parametric investigation is undertaken to analyze the impact of various parameters related to graphene platelets (GPLs) and distribution types of porosity on the damping behavior of multilayer PFG-GPRC plates. © The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature 2023.
An experimental evaluation of the microstructure, mechanical and functional fatigue properties of the boron-doped Cu-Al-Be SMA wires
(Elsevier Ltd, 2021) Singh, R.K.; Biswas, P.; Murigendrappa, S.M.; Kattimani, S.
An experimental evaluation of the microstructure, mechanical and functional fatigue properties of the Cu-11.70Al-0.45Be doped with Bx (x = 0.05, 0.10, 0.12, and 0.14 wt%) SMA wires has been carried out. The experiments were performed to investigate microstructure, phase/precipitates, and transformation temperatures for both as-cast and wire samples. Furthermore, tensile properties, shape recovery ratio, and functional fatigue evaluation have also been carried out for the wire samples. The investigation shows that the addition of the minor amount of boron and secondary processes involved during the specimen preparation induced excellent grain refinement. The addition of boron decreased transformation temperatures; however, there was not a considerable change observed due to the secondary process. It was observed that tensile properties increases with the boron addition, and complete shape recovery was observed for all the selected alloys. Finally, functional fatigue tests were conducted under constant stress condition and observed that the number of cycles until the failure has increased and more distance recovery was achieved with an increase in boron doping. © 2021
Analysis of 3D-Printed Nylon/PETG Hybrid Polymer Laminate Plate for Wind Turbine Nacelle Application
(Springer, 2025) Senthil Murugan, S.S.; Shankar, E.; Kattimani, S.; Abish, V.R.; Anbu, G.; Avinash, A.R.
This study aims to develop hybrid polymer laminate (HPL) structure utilizing the 3D printing fused filament fabrication (FFF) method and analyze the printing process. The HPL plates were fabricated using PETG and nylon 66 thermoplastic polymers at varying infill densities, printing speeds, and layer thicknesses. The experimental setup followed a fixed matrix based on the L9 orthogonal array (OA). Each HPL consisted of a bottom layer printed with nylon 66, with PETG layers sandwiched on top. Subsequently, the samples underwent testing using a UTM m/c to assess their tensile and flexural strength, as well as printing efficiency. Warping was observed on the printed samples, with a maximum tensile strength of 27 MPa and flexural strength of 14.5 MPa recorded. Notably, different strength values were observed when altering printing parameters. While the printing process was successful, the resulting HPL exhibited slightly lower strength compared to PETG or nylon 66 filaments. The study achieved a maximum printing efficiency of 90% (?), with the layer thickness parameter significantly impacting tensile properties. These findings offer valuable insights and required for various industrial applications, including wind turbines, electronics, automotive, and aeronautics. © The Author(s), under exclusive licence to The National Academy of Sciences, India 2024.
Analysis of UNS S31603 ferrous joint made by rotary friction welding
(Springer, 2024) Senthil Murugan, S.; Girisankar, S.; Devanathan, C.; Kattimani, S.
This study delves into the effects of employing low friction pressure and high axial penetration during the fabrication of friction-welded joints using UNS S31603 stainless steel. The experiments were conducted using a continuous-drive rotary friction welding machine. Crucially, the research showcases the feasibility of creating robust welds in the metal, surpassing the strength of the parent metal. The resulting weld interfaces were remarkably narrow and well-defined. The mechanical properties of the welded joints, including tensile strength, yield strength, microhardness, impact toughness, and bending/flexural strength, were meticulously evaluated following ASTM standards. The findings indicate that the welded joints exhibited impressive tensile strength, approximately 803 MPa, and withstood a peak load of 52.0 kN. Additionally, these joints demonstrated a maximum elongation of 15.3% and a yield strength of 714.0 MPa. When subjected to bending conditions, similar joints made of UNS S31603 withstood loads of up to 19.0 kN before experiencing crack propagation. Ductility was observed in the fracture mode within the weld region, characterized by the formation of cup and cone necking, highlighting the joints' ductile behaviour. Furthermore, the joint efficiency was calculated to be over 100%. Utilizing these specific parameters, this method resulted in a maximum axial shortening or material loss of approximately 14 mm. © Indian Academy of Sciences 2024.
Buckling analysis of skew magneto-electro-elastic plates under in-plane loading
(SAGE Publications Ltd info@sagepub.co.uk, 2018) Kiran, M.C.; Kattimani, S.
This article deals with the study of buckling behaviour of multilayered skew magneto-electro-elastic plate under uniaxial and biaxial in-plane loadings. The skew edges of the skew magneto-electro-elastic plate are obtained by transforming the local skew coordinate to the global using a transformation matrix. The displacement fields corresponding to the first-order shear deformation theory along with constitutive equations of magneto-electro-elastic materials are used to develop a finite element model. The finite element model encompasses the coupling between electric, magnetic and elastic fields. The in-plane stress distribution within the skew magneto-electro-elastic plate due to the enacted force is considered to be equivalent to the applied in-plane compressive loads in the pre-buckling range. This stress distribution is used to derive the potential energy functional of the skew magneto-electro-elastic plate. The non-dimensional critical buckling load is attained from the solution of the allied linear eigenvalue problem. Influence of skew angle, stacking sequence, span-to-thickness ratio, aspect ratio and boundary condition on the critical buckling load and their corresponding mode shapes is investigated. © 2018, © The Author(s) 2018.
Characterisation of fatigue delamination growth in plain woven hybrid laminated composites subjected to Mode-I loading
(Elsevier B.V., 2024) Suman, M.L.J.; Murigendrappa, S.M.; Kattimani, S.
Effect of similar and dissimilar crack plane interface configuration on fatigue delamination growth in plain woven hybrid composite laminates under Mode-I has been investigated. Constant displacement amplitude fatigue testing with displacement ratio of 0.1 was carried out on 3 configurations of plain woven glass/carbon epoxy composite laminates. A power law like fit between recorded delamination length and corresponding cycle was used to predict crack length for each of the cycle. Delamination growth rate,da/dN is computed by differentiating the expression of power-law like fit. The obtained crack growth rate for each of the specimens were plotted with respect to two normalised functions, G^Imax=GImax(a)/GIR(a) where GImax is maximum mode-I energy release rate and GIR(a) is the interlaminar fracture toughness resistance and ΔG^Ieff=G^Imax-G^Imin2 as crack driving parameters computed on the basis of Modified Beam Theory (MBT) and Valvo's mode partition method (MPV) are used in Paris relation to quantify delamination propagation. It is observed that the exponent values predicted by MBT method for G^Imax is lower as compared to ΔG^Ieff. Whereas, exponent values predicted for G^Imax is higher as compared to ΔG^Ieff predicted by MPV method. The higher the exponent value, the higher is the sensitivity of the model leading to uncertainties in the crack growth prediction. Also, it is to be noted that cyclic loading effect is when both GImax and GImin is considered, the use of ΔG^Ieff as crack driving parameter to quantify delamination propagation is justified. Secondly, MBT method does not account for the mode-mixity arising due to hybrid material configuration as in the case of Local Symmetry Fatigue (LSF) and Asymmetry Fatigue (ASF) specimens. Hence, results in higher exponent as compared to MPV method. On the other side, the G^Imax and ΔG^Ieff computed on the basis of MPV method is the pure Mode-I component deduced from the total energy release rate of mode-mixity. The equations of curve fitting is very much the same for Simple Symmetry Fatigue (SSF) specimens indicating that MBT and MPV methods predict pure Mode-I behaviour for symmetric configuration for delamination growth under fatigue Mode-I loading. From the composite laminate configuration point of view, LSF specimens have higher exponents as compared to ASF and SSF specimens indicating, local symmetry configuration laminates are highly sensitive to the small uncertainties and results in unstable crack growth. Comparison of results of all hybrid composite laminates shows that the normalised functions of G^Imax and ΔG^Ieff as crack driving parameters computed on the basis of MPV method is able to capture the effect of interlayers and stacking effect on the delamination growth in hybrid plain woven composites in fatigue loading and MPV method is found to be not sensitive to G^Imax and ΔG^Ieff for displacement ratio of 0.1. © 2023 Elsevier Ltd
Coupled evaluation of the free vibration characteristics of magneto-electro-elastic skew plates in hygrothermal environment
(Techno-Press, 2019) Mahesh, V.; Kattimani, S.; Harursampath, D.; Nguyen, N.-T.
The present article addresses the coupled free vibration problem of skew magneto-electro-elastic plates (SMEE) considering the temperature-moisture dependent material properties. The plate kinematics follows Reddy?s higher order shear deformation theory. With the aid of finite element methods, the governing equations of motion are derived considering the Hamilton?s principle and solved by adopting condensation technique. The influence of different temperature and moisture dependent empirical constants on the frequency response of SMEE plate has been assessed. In addition, the natural frequencies corresponding to various fields are evaluated and the effect of empirical constants on these coupled frequencies is determined. A detailed parametric study has been carried out to assess the individual effects of temperature and moisture dependent empirical constants along with their combined effect, aspect ratio, length-to-width ratio, stacking sequence and boundary conditions. The results reveal that the external environment as well as the geometrical skewness has a significant influence on the stiffness of the SMEE plates. © 2019 Techno-Press, Ltd.
Design of novel test rig for prosthetic finger distal interphalangeal and phalanx strengths
(Wolters Kluwer Health, 2025) Madhu Mohan, R.; Kattimani, S.; Koorata, P.K.; Girisha, C.
Testing is one of the most significant phases of any engineering process, the last process followed by conceptualization, designing, and fabricating. If the testing outcomes are not genealogy sensible measurables, then eventually it calls for a redesign overhaul. Existing testing equipment to analyze the load and failures are conventional digital universal testing machines with minimum jigs and fixtures. In addition, the existing fixtures cannot be adapted to the anatomy of a human finger. Consequently, the present work explores the best possible design of a jig for testing the naturally articulated movement of a human finger (prosthetic wear-on). Furthermore, the present jig design checks a wide range of parameters such as freedom of motion, a path along with curvature, load, failures, and intermittent positions of applied load, which is adaptable to existing universal testing machines available for broader applications. © 2024 International Society for Prosthetics and Orthotics.
Development of Metal Matrix Composites Through Liquid State Technique
(CRC Press, 2025) Senthil Murugan, S.; Kattimani, S.
The stir casting process (SC or SCP) is an established technique for achieving effective bonding and mixing between matrix materials and ceramic reinforcements. This method facilitates chemical interactions through vortex flow within the melt, ensuring uniform distribution of the reinforcements. While SCP has demonstrated notable success in producing aluminium and magnesium matrix composites, its potential for polymer composite development is still being explored, offering promising opportunities for innovation. This chapter examines the research advancements in SCP for various materials, its industrial challenges, and its evolving applications. Effective degassing is identified as a critical step in the production of high-quality metal matrix composites (MMCs). SCP-derived MMCs find extensive applications in the automotive and aerospace industries, underscoring their significance. The versatility of SCP extends to the fabrication of advanced materials such as hybrid metal composites, nanocomposites (NCs), functionally graded materials (FGMs), and ultra-fine graded composites (UFGs) when combined with other manufacturing methods. The performance and outcome of SCP are influenced by factors such as process temperature, reinforcement proportion, and key process parameters. Further research is essential to optimise these parameters, explore novel applications, and fully realise the potential of SCP in producing next-generation materials. © 2025 selection and editorial matter, Tharmaraj Ramakrishnan and PM Gopal; individual chapters, the contributors.
Effect of BTO piezoceramic on the mechanical and dielectric properties of 3D-printed PLA.BTO functional polymer composite
(Springer Nature, 2025) Senthil Murugan, S.; Kattimani, S.; Saminathan, R.
The development of polymer composite materials for additive manufacturing is critical for advancing industrial applications. This study enhances the functional performance of poly-lactic acid (PLA) by incorporating barium titanate (BTO/BaTiO?) particles. Uniform dispersion of BTO within the PLA matrix was achieved, and filaments were fabricated using fused deposition modelling (FDM) with a 60% infill rate, adhering to ASTM standards. The influence of BTO fillers on the mechanical and dielectric properties of PLA.BTO composites were analysed and compared to pure PLA. FESEM microstructural analysis confirmed distinct layering, defect-free deposition, and uniform BTO distribution. Mechanical testing revealed notable improvements, including increases in tensile strength (16.4%), flexural strength (17.1%), shore hardness (4.7%), impact strength (17.7%), and drop-weight energy absorption for a 5 mm plate (26%), attributed to enhanced interfacial bonding and reduced void formation. The dielectric properties exhibited significant enhancements, with a 12.9% increase in dielectric strength, a 15% higher dielectric constant, an 8% greater breakdown strength, and a 21.74% rise in electrical susceptibility. Furthermore, reductions in loss tangent (19.1%), AC conductivity (7.8%), and dielectric loss (6.8%) demonstrated the material’s ability to store and withstand electric fields efficiently. Ferroelectric analysis revealed improved remanence, coercivity, and polarization, underscoring the composite’s potential as a piezoelectric material. These findings highlight the suitability of PLA.BTO composites for energy storage devices, sensors, and biodegradable functional applications, offering a promising balance of mechanical durability and superior dielectric performance. © Qatar University and Springer Nature Switzerland AG 2025.
Effect of different geometrical non-uniformities on nonlinear vibration of porous functionally graded skew plates: A finite element study
(China Ordnance Industry Corporation, 2022) Kumar H S, H.S.; Kattimani, S.
This article presents the investigation of nonlinear vibration analysis of tapered porous functionally graded skew (TPFGS) plate considering the effects of geometrical non-uniformities to optimize the thickness in the structural design. The TPFGS plate is analyzed considering linearly, bi-linearly, and exponentially varying thicknesses. The plate's effective material properties are tailor-made using a modified power-law distribution in which gradation varies along the thickness direction of the TPFGS plate. Incorporating the non-linear finite element formulation to develop the kinematic equation's displacement model for the TPFGS plate is based on the first-order shear deformation theory (FSDT) in conjunction with von Karman's nonlinearity. The nonlinear governing equations are established by Hamilton's principle. The direct iterative method is adopted to solve the nonlinear mathematical relations to obtain the nonlinear frequencies. The influence of the porosity distributions and porosity parameter indices on the nonlinear frequency responses of the TPFGS plate for different skew angles and variable thicknesses are studied for various geometrical parameters. The influence of taper ratio, variable thickness, skewness, porosity distributions, gradation, and boundary conditions on the plate's nonlinear vibration is demonstrated. The nonlinear frequency analysis reveals that the geometrical non-uniformities and porosities significantly influence the porous functionally graded plates with varying thickness than the uniform thickness. Besides, exponentially and linearly variable thicknesses can be considered for the thickness optimizations of TPFGS plates in the structural design. © 2021 China Ordnance Society
Effect of piezoelectric ceramic on natural frequency, structural, and thermal properties of additively manufactured PLA/BTO composite structure
(Elsevier Ltd, 2025) Senthil Murugan, S.S.; Kattimani, S.
This study investigates the fabrication and characterisation of filaments and 3D-printed samples using polylactic acid (PLA) and PLA/BTO (Barium Titanate) composites via fused deposition additive manufacturing (FDAM). PLA/BTO composite filaments were prepared by blending PLA granules with BTO particles using hot extrusion. Samples were 3D printed under controlled parameters and analyzed for dynamic, thermal, and structural properties. The inclusion of BTO significantly enhanced natural frequency (11 Hz-first peak) and structural rigidity compared to pure PLA (8 Hz-first peak), particularly under cantilever beam configurations. Microstructural analysis via optical and field emission scanning electron microscopy (FESEM) revealed uniform particle dispersion and good layer adhesion in composites with a peak width of 340 ?m. Energy-dispersive X-ray diffraction (EDS) study insisted that the presence of BTO improves functionality with minimal reinforcement with other trace elements. X-ray diffraction (XRD) confirmed increased crystallinity in PLA/BTO samples and improved alignment of the crystalline regions post-FDAM process, while Fourier transform infrared spectroscopy (FTIR) demonstrated molecular interactions between PLA and BTO and highlights the structural modifications in the composite due to the act of BTO reinforcement as nucleating agent. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) highlighted enhanced thermal stability and modified crystallinity due to BTO incorporation. Printed PLA/BTO demonstrates the highest resistance to thermal degradation than pure PLA, with degradation onset at an elevated temperature. Results validate the suitability of PLA/BTO composites for applications requiring tailored dynamic, thermal, and structural properties, emphasizing the FDAM process's potential for advanced material development. © 2025 Elsevier Ltd and Techna Group S.r.l.
Effect of Piezoelectric Interphase Thickness on Nonlinear Behavior of Multiphase Magneto–Electro–Elastic Fibrous Composite Plate
(Springer, 2021) Kattimani, S.
This paper presents the effect of piezoelectric interphase thickness on the nonlinear behavior of multiphase magneto–electro–elastic (MMEE) fibrous composite plates. A layer-wise shear deformation theory has been considered for the kinematics of the MMEE plate integrated with the principle of virtual work in a three-dimensional finite element (FE) formulation. To incorporate the effect of piezoelectric interphase thickness on the nonlinear behavior of the plate, the multiphase fibrous composite substrate considered for the evaluation is consists of carbon fibers surrounded by a thin coating of piezoelectric fiber (PZT-7A) embedded in piezomagnetic (cobalt ferrite-CoFe2O4) matrix material. The influence of piezoelectric and piezomagnetic coupled fields on the stiffness and nonlinear behavior of MMEE (CoFe2O4/PZT-7A/Carbon) composites considerably varies with PZT-7A interphase thickness. Thus, the transient response, nonlinear frequency ratio, and nonlinear deflection of the structure remarkably changes. Besides, the variation of fiber/matrix volume fraction and interphase thickness exhibits tremendous influence on the nonlinear behavior of the MMEE fibrous composite plate. Further attention has been paid to investigate the influence of boundary conditions, aspect ratio, volume fraction, and coupled fields on the nonlinear behavior of the MMEE fibrous composite plate. © 2021, Krishtel eMaging Solutions Private Limited.
Effect of porosity on active damping of geometrically nonlinear vibrations of a functionally graded magneto-electro-elastic plate
(China Ordnance Industry Corporation, 2022) Esayas, L.S.; Kattimani, S.
This paper investigates the effect of porosity on active damping of geometrically nonlinear vibrations (GNLV) of the magneto-electro-elastic (MEE) functionally graded (FG) plates incorporated with active treatment constricted layer damping (ATCLD) patches. The perpendicularly/slanted reinforced 1–3 piezoelectric composite (1–3 PZC) constricting layer. The constricted viscoelastic layer of the ATCLD is modeled in the time-domain using Golla-Hughes-McTavish (GHM) technique. Different types of porosity distribution in the porous magneto-electro-elastic functionally graded PMEE-FG plate graded in the thickness direction. Considering the coupling effects among elasticity, electrical, and magnetic fields, a three-dimensional finite element (FE) model for the smart PMEE-FG plate is obtained by incorporating the theory of layer-wise shear deformation. The geometric nonlinearity adopts the von Kármán principle. The study presents the effects of a variant of a power-law index, porosity index, the material gradation, three types of porosity distribution, boundary conditions, and the piezoelectric fiber's orientation angle on the control of GNLV of the PMEE-FG plates. The results reveal that the FG substrate layers' porosity significantly impacts the nonlinear behavior and damping performance of the PMEE-FG plates. © 2021 China Ordnance Society
Effect of radiofrequency coil and primary magnetic field on radiolucent composite plates
(SAGE Publications Inc., 2023) Gawande, A.S.; Mukka Ramachanra, S.; kamyab, H.; Nguyen, N.-T.; Kattimani, S.
Magnetic Resonance Imaging (MRI) systems need a material compatible with the imaging technique with lesser attenuation and provide accurate images without distortion. Carbon fibers are the best-suited materials for x-ray applications because of their radiolucent properties and reduced attenuation characteristics. However, carbon fiber produces images with distortion in the MRI system by absorbing electromagnetic energy because of its conductive nature. In the present study, five different fiber-reinforced radiolucent composite plates are analyzed to predict their suitability for a radio frequency coil and the effect of a primary magnetic field of 1.5 T and 3.0 T on mechanical responses. Simulation models are built to explore the impact of electromagnetic waves and birdcage coil configurations on composite material and quantify the temperature changes caused due to energy absorption. A multiphysics coupling simulation is being used to understand the effect of stacking sequence, ply orientation, and boundary conditions on the response of composite plates under an electro-magneto-mechanical environment. © The Author(s) 2022.
Effect of similar and dissimilar interface layers on delamination in hybrid plain woven glass/carbon epoxy laminated composite double cantilever beam under Mode-I loading
(Elsevier B.V., 2021) Suman, M.L.J.; Murigendrappa, S.M.; Kattimani, S.
Effect of similar and dissimilar interface layers on delamination in hybrid plain woven glass/carbon epoxy laminated composite double cantilever beam under Mode-I loading has been investigated experimentally and analytically. Glass-glass, glass-carbon interface layers in three different configurations of hybrid plain woven glass/carbon epoxy laminated composites were fabricated. Valvo's mode partition method from the literature is utilised to compute individual modal contributions and total fracture toughness of the hybrid composite laminates. Mode-I fracture toughness contribution is compared with standard data reduction schemes of ASTM D5528-13. The comparison reveals that Valvo's mode partition method considers mode-mixity and provides conservative results. The Valvo's mode partition does not require any correction factors including curve fitting, it provides a straightforward method for evaluating fracture toughness as they are based on the mechanics of composite materials. The comparison of R-curves of hybrid configurations reveal that the insertion of carbon with glass at the interface of symmetric hybrid configuration enhances initial fracture toughness and stabilises whereas, with the change in layer configuration of anyone arm of the double-cantilever beam, the crack growth trend is also affected irrespective of same interface layers. The fractography analysis of delamination surfaces reveals that crack propagation through a resin-rich layer creates a rougher fracture surface resulting in higher energy dissipation as compared to crack propagation through resin-rich pockets. © 2021 Elsevier Ltd