Conference Papers
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Item Study on ballistic energy absorption capability of glass-epoxy and jute-epoxy-rubber sandwich composites(Trans Tech Publications Ltd ttp@transtec.ch, 2018) Rajole, S.; Ravishankar, K.S.; Kulkarni, S.M.High velocity impact analysis of natural fiber reinforced composites is essential as the trend is focused towards the development of light weight, environment-friendly, non-corrosive and economical materials. At present, the defence, aerospace and automobile sectors are using synthetic fiber composites which are expensive and non-eco-friendly. In the present study ballistic impact of jute-epoxy (JEC), glass-epoxy (GEC), jute-epoxy-rubber (JERC) sandwich composites are simulated with different thickness (1, 2 and 3 mm) and velocity variations (100, 200 and 300m/s) using Finite Element analysis software. Although different approaches to the analysis of the effect response of composite structures are available, numerical modeling is based on strict constitutive models is often preferred because it can provide valuable detailed information about the spatial and temporal distribution of damage during the impact. The ballistic parameters such as energy absorption, ballistic limit and fracture behaviors are predicted. The composite is made of 8 noded linear brick elements and the bullet/projectile is modeled as a discrete rigid element in which deformation behavior, energy absorption and penetration behaviors obtained are clearly represented. The simulation results predicted match well with the analytical results obtained. Among all the combination of the materials simulated, the sandwiches have better ballistic qualities. Energy absorption of sandwich(JERC) was found 67 percentage higher than GEC and 56 percentage higher than JEC laminate. In future, these materials can be the alternative materials for defence sector for bullet proofing. © 2018 Trans Tech Publications, Switzerland.Item Comparative study on filament wounded and laminated GFRP composites for tensile characterization(American Institute of Physics Inc. subs@aip.org, 2019) Biradar, S.; Joladarashi, S.; Rajole, S.; Hiremath, S.; Kulkarni, S.M.The demand of composite materials has increased tremendously in various industries such as processing industries in making tanks used to process chemicals, in commercial and domestic application such as to LPG cylinders, in automobile industries like in case of car bodies, fuel tanks, aerospace industries, where fuselage wings, landing gears, doors and many other parts of aircraft. The current demand for composites is mainly due to high strength to weight ratio. Hence, we need to understand criticality in the design of composite products. In this paper primarily focused on GFRP for pressure vessels. Hence in this work an initial study was done to compare tensile properties of filament wounded GFRP test coupons with laminated GFRP test coupons which are cut as per ASTM D3039, both these types of samples are fabricated by using glass fiber direct rovings of 2400TEX. Tensile testing samples are prepared by directly cutting test coupons from fabricated vessel and whereas in case of laminated GFRP specimen are cut using hand cutting tool. The obtained results are further compared with analytical results. From comparative study, it is found that there exists considerable difference between experimental and theoretical results for tensile strength and tensile modulus in case of specimens prepared from GFRP pressure vessel. The variation in results is mainly due to presence of void content, poor interfacial bonding between fiber and matrix, fiber fragmentation, improper spacing between fibers, the presence of all these possible defects are justified by fractography study of failed samples in a scanning electron microscope. Hence from fractography study it is clearly justified that why there is least percentage error in tensile properties of laminated composites. © 2018 Author(s).Item Effect of Mechanical properties on Multi Axially Forged LM4 Aluminium Alloy(Elsevier Ltd, 2020) Sajjan, S.S.; Kulkarni, M.V.; Ramesh, S.; Sharath, P.C.; Kumar, V.; Rajole, S.Commercially available LM4 Aluminum alloy was subjected through Severe Plastic Deformation (SPD) method by Multi-Axial Forging Process (MAF) in ambient temperature. In this process, the material was processed successfully up to 5 Passes and mechanical properties such as tensile strength, compression strength and hardness of the as received and processed samples at ambient temperature were evaluated. The MAF processed sample result showed that the ultimate strength, percentage elongation and compression strength improved by 55 MPa, 3.75% and 162 MPa respectively as compared with the unprocessed sample. Hardness also increased with the increase in the number of passes. In the case of microstructure, grain size reduced from 110 μm to 8 μm after subjecting the sample to MAF. Fractography explains the nature of the fracture from received to processed samples by decreasing the size of the dimple and the type of fracture observed was ductile in nature. Improvement in strength and hardness of processed samples was observed due to the grain refinement and high amount of density dislocation in the material during MAF. © 2018 Elsevier Ltd.Item Fault Detection and Health Condition Analysis of Single Stage Gear Box System(Springer Science and Business Media Deutschland GmbH info@springer-sbm.com, 2021) Mohiuddin, B.; Kivade, S.B.; Rajole, S.Every machine with the relative motion of parts produces sound and vibration. All the gear boxes usually generate vibrations and respective vibration signatures may be taken as referable characteristics if the condition of the gear is good. During working condition, whenever fault occurs, it may result in serious damage of the gear box. The change in the gear pair meshing could result in changes in vibration signals. The accelerometer mounting on the gear box system is the accurate task for assessment of pair of gear. So the technique of monitoring the condition is very essential to prevent and diagnose the vibration of gear box. Nowadays damage identification and condition monitoring of gear boxes in the industrial machinery have received more attention from the researchers. To analyze the various fault and problems related with gear box failure in a working environment efficiently and accurately, few technologies like material technology, information technology, and processing of signals, etc. bring latest solutions. For the assessment of industrial gear boxes, many investigations are carried out for monitoring the condition of machinery. Signal processing and vibration analysis techniques are well known and much suitable for industrial practices. Since, the signals of vibrations from the gear box are transient and non-stationary in nature. Every technique has some disadvantages and may not be used in all condition, i.e., few failure detection is not possible by simple vibration method. At an early stage, simple analysis by spectral is not very successful to find the injury of gear. © 2021, Springer Nature Singapore Pte Ltd.