Faculty Publications
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Item Ballistic impact analysis of multilayered armour system using finite element analysis(Elsevier, 2024) Doddamani, S.; Kulkarni, S.M.; Joladarashi, S.; Mohan Kumar, T.S.; Gurjar, A.K.The application of finite element analysis (FEA) to the ballistic impact analysis of polymer composites used in armor is covered in this chapter. This study aims to assess polymer composite armor materials' performance and establish their resistance to high-velocity projectile impacts. The use of FEA enables accurate simulations of the impact process that take into consideration the properties of the materials, the geometry of the projectile and the armor panel, and the impact conditions. The investigation' findings shed important light on how the polymer composite armor responds to impacts and its capacity to absorb and dissipate impact energy. For the development of cutting-edge armor materials and the multiscale modeling method of armor design, this information is essential. The chapter ends with recommendations for further research as well as a discussion of the difficulties and restrictions of employing FEA for ballistic impact analysis. © 2024 Elsevier Ltd. All rights are reserved including those for text and data mining AI training and similar technologies.Item Investigation of fracture toughness analysis of polymer composites using finite element analysis(Elsevier, 2024) Doddamani, S.; Begum, Y.; Bharath, K.N.; Rajesh, A.M.; Mohamed, K.K.This chapter includes a study on using finite element analysis (FEA) to investigate the fracture toughness of polymer composites. This study’s objective is to assess polymer composites' fracture toughness. By considering the material properties and stress distributions, multiscale modeling approaches in FEA enable a thorough assessment of the material behavior under various loading circumstances. The analysis’s findings shed important light on the polymer composites' fracture toughness. The chapter ends with recommendations for further research and a review of the benefits and drawbacks of employing multiscale modeling and FEA techniques to analyze fracture toughness in polymer composites. The results of this work have significant ramifications for polymer composite structure design and optimization, particularly in applications requiring high fracture toughness. © 2024 Elsevier Ltd. All rights are reserved including those for text and data mining AI training and similar technologies.Item Vibration Analysis of Composite Viscoelastic Core Sandwich Beam Using Active Control Techniques(Springer Science and Business Media Deutschland GmbH, 2024) Raghavendra, P.; Gatty, A.S.; Rajesh, H.; Deepak, T.N.; Rawal, Y.; Nagiredla, S.; Joladarashi, S.Vibration control is swiftly advancing in research, with diverse techniques being investigated to minimize detrimental vibration levels. Compared to metallic alloys, composite materials offer superior material properties while being lightweight. The main objective of this study is to develop active control techniques on Carbon/Glass Epoxy-reinforced composite sandwich beams with viscoelastic core using Proportional Integral Derivative (PID), Linear Quadratic Regulator (LQR), and Linear Quadratic Gaussian (LQG) Controllers. The approach involves conducting an experiment to obtain the Transient Response of the beams subjected to free vibration, which is then utilized to obtain the Transfer Function and State Space variables. MATLAB-Simulink obtained transfer function is used for implementing controllers to actively attenuate vibrational amplitudes and settling time. The outcomes reveal a significant reduction in settling time and vibrational peak amplitudes. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.Item Review on fiber composites for sustainable high strain rate applications(Elsevier Inc., 2025) Lakshme Gowda, D.M.; Bhat, R.S.; Rangappa, S.M.; Siengchin, S.Over the past two decades, the growing demand for sustainable, high-performance materials has driven significant advancements in fiber reinforced polymer composites (FRPCs), particularly for dynamic and ballistic applications. This review provides an integrated overview of recent developments, highlighting sustainable reinforcements, novel stacking configurations, and advanced machine learning (ML) predictive approaches. Particular emphasis is placed on bio-inspired helicoidal laminates and hybrid architectures, which offer superior energy absorption, damage tolerance, and impact mitigation. Hybrid laminates incorporating satin weaves, high-modulus fibers, and compliant matrices enhance post-impact toughness and better structural integrity. Additionally, embedding a high-hardness (70–90 Shore A) rubber core with a compliant matrix mitigates conical crack propagation, improves strain rate sensitivity, and reduces delamination under both low- and high-velocity impacts. The dynamic response of FRPCs is examined using experimental techniques such as Split Hopkinson Pressure Bar (SHPB) testing and impact assessments, revealing the influence of design variables on strain-rate-dependent behavior. To support material selection and design optimization in fiber composites, ML techniques, Ashby charts, and Multi-Criteria Decision-Making (MCDM) frameworks are explored, balancing performance, sustainability, and manufacturability. Failure mechanisms such as delamination, fiber pull-out, and matrix cracking are analyzed with respect to hybridization strategies and environmental effects. Finite element analysis (FEA) tools, including ABAQUS, ANSYS AUTODYN, and LS-DYNA, are reviewed for their predictive accuracy, validated against experimental results. Standardized testing protocols (ASTM D7136, D7137, F1342; NIJ-0101.06) ensure the consistent evaluation of both flexible and rigid armor systems. The review also discusses manufacturing advancements such as resin transfer molding (RTM) and filament winding, which improve scalability and reduce waste. Non-destructive testing (NDT) methods, including acoustic emission, ultrasonic C-scanning, and X-ray CT, are highlighted for real-time damage assessment. Finally, integrating ML algorithms such as MLP, SVM, RF, and CNN with experimental and simulation data enhances predictive modeling, damage classification, and tailored composite design. This convergence of bio-inspired design, computational tools, and intelligent systems is accelerating the development of next-generation FRPCs for aerospace, defense, automotive, and civil engineering applications. © 2025 The AuthorsItem Heat transfer during the solidification of an Al-Cu-Si alloy (LM4) and commercial pure tin in single steel, graphite, and graphite-lined metallic (composite) molds was investigated. Experiments were carried out at three different superheats. In the case of composite molds, the effect of the thickness of the graphite lining and the outer wall on heat transfer was studied. Temperatures at known locations inside the mold and casting were used to solve the Fourier heat conduction equation inversely to yield the casting/mold interfacial heat flux transients. Increased melt superheats and higher thermal conductivity of the mold material led to an increase in the peak heat flux at the metal/mold interface. Factorial experiments indicated that the mold material had a significant effect on the peak heat flux at the 5% level of significance. The ratio of graphite lining to outer steel wall and superheat had a significant effect on the peak heat flux in significance range varying between 5 and 25%. A heat flux model was proposed to estimate the maximum heat flux transients at different superheat levels of 25 to 75°C for any metal/mold combinations having a thermal diffusivity ratio (?R) varying between 0.25 and 6.96. The heat flow models could be used to estimate interfacial heat flux transients from the thermophysical properties of the mold and cast materials and the melt superheat. Metallographic analysis indicated finer microstructures for castings poured at increased melt superheats and cast in high-thermal diffusivity molds.(Effect of superheat, mold, and casting materials on the metal/mold interfacial heat transfer during solidification in graphite-lined permanent molds) Prabhu, K.; Suresha, K.M.2004Item Epoxy systems with and without different volume fractions of fly ash particulate fillers are made and their absorption due to immersion in saline water maintained at room temperature are established through weight measurements recorded up to 100h. The 100-h exposed samples are additionally subjected to compression tests to evaluate the strength. The results show that both neat epoxy and fly ash-bearing composites exhibit differing levels of aqueous medium absorption - it being less in ash-free samples. When the ash content in the system is large, the absorption levels are high. The data further revealed that the unexposed samples generally record an increasing strength value with ash content. However, for the exposed cases, a reversal in trend with the ash content is noticed. Attempts to explain these differing trends are made in this work by analyzing the features observed on the surface of compression-failed samples using fractography employing scanning electron microscopy (SEM). © 2005 Sage Publications.(Compression strength of saline water-exposed epoxy system containing fly ash particles) Kishore; Barpanda, P.; Kulkarni, S.M.2005Item The inhibition efficiency of Glycyl Glycine (GG) on the corrosion behaviour of Al-SiC(p) composite in 0.01, 0.1 and 1.0 N HCl solution has been investigated in the temperature range 30°-50°C using polarization techniques. The results indicate that GG acts as an anodic inhibitor and is chemisorbed following Temkin's model. The inhibitor efficiency increases with increase in inhibitor concentration and also with increase in temperature for a given inhibitor concentration. © 2006 SAEST.(Glycyl glycine as corrosion inhibitor for aluminium silicon carbide composite in hydrochloric acid) Rao, S.A.; Padmalatha; Nayak, J.; Nityananda Shetty, A.N.2006Item Higher order refined computational models for the free vibration analysis of antisymmetric angle ply plates(2008) Swaminathan, K.; Patil, S.S.Analytical formulations using two higher order refined displacement models have been developed and solutions presented for the first time to the natural frequency analysis of antisymmetric angle-ply composite and sandwich plates. These computational models already reported in the literature are based on Taylor's series expansion of the displacements in the thickness coordinate and consider the realistic parabolic distribution of transverse shear strains through the laminate thickness. One of them, with 12 degrees of freedom, considers the effects of both transverse shear and normal strain/stress while the other with 9 degrees of freedom includes only the effect of transverse shear deformation. In addition to above, a few higher order models and the first order model developed by other investigators and available in the literature are also considered for the evaluation. A simply supported plate is considered throughout as a test problem. The equations of motion are obtained using Hamilton's principle. Solutions are obtained in closed form using Navier's technique by solving the eigenvalue equation. Plates with varying slenderness ratios, number of layers, fiber orientations, degrees of anisotropy, edge ratios and thickness of core to thickness of face sheet ratios are considered for the analysis. Accuracy of the theoretical formulations and the solution method is first ascertained by comparing the results with those already available in the literature. After establishing the accuracy of the solutions, extensive numerical results are presented for the free vibration analysis of multilayer antisymmetric angle-ply composite and sandwich plates using all the models, which will serve as a benchmark for future investigations. © SAGE Publications 2008.Item The inhibition action of ethyl-2-phenyl hydrozono-3-oxobutyrate on the corrosion of 6061 Al alloy/SiCp composite in hydrochloric acid medium(Sociedad Chilena de Quimica, 2010) Kini U, U.A.; Shetty, P.; Shetty, S.D.; Isloor, A.M.; Herle, R.The inhibition behavior of ethyl-2-phenyl hydrozono-3-oxobutyrate on the corrosion of 6061 Al alloy/SiCp composite in 0.1, 0.5 and 1 N hydrochloric acid solution at four different temperatures (30-60 °C) has been investigated using potentiostatic polarization techniques and weight loss method. The results indicated that the corrosion inhibition efficiency and the extent of surface coverage were increased with the increase in inhibitor concentration up to a critical concentration. The adsorption of the inhibitor compound on the composite surface was found to obey Temkins' and Langmuir adsorption isotherms. The potentiostatic polarization results have revealed that oxobutyrate acts as an efficient cathodic inhibitor for the corrosion of 6061 Al alloy/SiCp composite in HCl medium. The thermodynamic parameters for the corrosion and adsorption processes were determined. © 2010.Item Potential use of natural fiber composite materials in India(2010) Saravana Bavan, D.; Mohan Kumar, G.C.M.This study focuses on the potential use of natural fibers in composite materials, their availability, processing features, mechanical and physical properties, and some of their applications in India. © 2010 The Author(s).