Faculty Publications
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Item Frequency and deflection analysis of cenosphere/glass fiber interply hybrid composite cantilever beam(American Institute of Physics Inc. subs@aip.org, 2018) Bharath, J.; Joladarashi, S.; Biradar, S.; Kumar, P.N.Interply hybrid laminates contain plies made of two or more different composite systems. Hybrid composites have unique features that can be used to meet specified design requirements in a more cost-effective way than nonhybrid composites. They offer many advantages over conventional composites including balanced strength and stiffness, enhanced bending and membrane mechanical properties, balanced thermal distortion stability, improved fatigue/impact resistance, improved fracture toughness and crack arresting properties, reduced weight and cost. In this paper an interply hybrid laminate composite containing Cenosphere reinforced polymer composite core and glass fiber reinforced polymer composite skin is analysied and effect of volume fraction of filler on frequency and load v/s deflection of hybrid composite are studied. Cenosphere reinforced polymer composite has increased specific strength, specific stiffness, specific density, savings in cost and weight. Glass fiber reinforced polymer composite has higher torsional rigidity when compared to metals. These laminate composites are fabricated to meet several structural applications and hence there is a need to study their vibration and deflection properties. Experimental investigation starts with fabrication of interply hybrid composite with cores of cenosphere reinforced epoxy composite volume fractions of CE 15, CE 25, CE15-UC as per ASTM E756-05C, and glasss fiber reinforced epoxy skin, cast product of required dimension by selecting glass fibre of proper thickness which is currently 0.25mm E-glass bidirectional woven glass fabric having density 2500kg/m3, in standard from cast parts of size 230mmX230mmX5mm in an Aluminum mould. Modal analysis of cantilever beam is performed to study the variation of natural frequency with strain gauge and the commercially available Lab-VIEW software and deflection in each of the cases by optical Laser Displacement Measurement Sensor to perform Load versus Deflection Analysis. Young's Modulus values obtained from deflection equation of cantilever beam with different respective load versus deflection values are compared and validated with value obtained using first mode of natural frequency equation of cantilever beam. © 2018 Author(s).Item FE analysis of FRP pressure vessel(Trans Tech Publications Ltd ttp@transtec.ch, 2019) Biradar, S.; Joladarashi, J.; Kulkarni, S.M.In this paper the main focus is on analyzing the effect of various parameters like winding angle, winding pattern and fiber volume fraction on the stresses generation in a composite pressure vessel using Finite Element (FE) approach. The present study makes use of three different composite materials namely GFRP (Glass Fiber Reinforced Plastic), CFRP (Carbon Fiber Reinforced Plastic) and AFRP (Aramid Fiber Reinforced Plastic). Further they are compared with metallic pressure vessel (LCS-Low Carbon Steel, Al 6061-T6-Aluminium 6061- T6) to assess their potentiality as a substitute to metallic pressure vessels. Based on Maximum Specific Stress (MSS) results observations it is concluded that optimum parameters suggested for fabrication of pressure vessel are winding angle ±55o, fiber volume fraction, Vf of 0.55 and winding pattern of ((±∅°2)/90°2/(±∅°2)). Following AFRP, CFRP and GFRP provides better performance when compared with LCS and Al 6061 T6 based on MSS value. Considering the availability, cost and application factors it can be concluded that GFRP can be conveniently used as substitute for metallic pressure vessels. © 2019 Trans Tech Publications, SwitzerlandItem 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 Investigation on mechanical behaviour of filament wound glass/epoxy composites subjected to water absorption and also tribological studies using Taguchi method(Elsevier Ltd, 2020) Biradar, S.; Joladarashi, S.; Kulkarni, S.M.The current study is mainly focused on the mechanical and tribological behaviour of GEC (Glass Epoxy Composites) (GEC- fabricated using filament winding technique) over the effect of various water immersion examinations for a defined time limit. In this study we mainly focus on filament wound glass/epoxy composite samples directly taken from composite pressure vessel. The important aspect of this study is to understand and investigate the percentage reduction or increase in the various mechanical and tribological properties under the influence of moisture. Here three (sea water, purified/distil water, boiling water) water containers where samples are treated as per water absorption test ASTM standard. These treated samples are examined for different mechanical strengths. From impact testing, the influence of boiling water on impact strength of glass/epoxy is high (impact strength in increasing order untreated < distilled < sea < boiling) when compared with other cases. Similar outcomes have been observed in case bending test also. Presence of water molecules enhances mechanical strength as water particles fills the gap or delays the voids or imperfections of samples to reach the boundaries. GEC samples made of filament winding process are examined for wet slurry erosion wear in an erosion testing machine as per the respective ASTM standard. The selection of number of experiments and identifying the most influencing parameter is done using the DOE (Design of Experiments) tool Taguchi L9 method. In the outcomes, erosion rate of glass/epoxy composite have highest influence of large sized sand particles with sand concentration 900 g, at a spindle speed of 1000 rpm. Whereas the smaller sand particles with lesser sand concentration have least impact on the erosion rate. © 2019 Elsevier Ltd. All rights reserved.Item Highlighting Nerves in Images for Ultrasound Guided Regional Anesthesia(Institute of Electrical and Electronics Engineers Inc., 2020) Akkasaligar, P.T.; Koolagudi, S.G.; Biradar, S.; Hotagi, P.; Badiger, S.Surgery is a treatment given to the patient, when patient is having injuries in the body parts. While doing the surgery the patient will undergo pain and discomfort, to reduce the pain of patient anesthesia is given before surgery. There are many types of anesthesia procedure called local, regional and general. Local anesthesia is given to specific part of the body; general anesthesia is where the patient is completely senseless. Regional anesthesia is procedure, where anesthetist does injection near a class of nerves to numb the area of human body that requires surgery. There is difference in structure of every person. This makes doctor hard to detect nerve in internal organ. Ultrasound image provide information about structure of body which can be used for regional anesthesia. Ultrasonography is the safest method compared to the other imaging techniques like Xray, CT, and MRI; because it is not based on ionizing radiation. In this paper, we simplify the issue of detection of nerve in ultrasound image. For input, image such as ultrasound images of brachial plexus are used. Initially in preprocessing, filtering technique is used to remove noise from ultrasound image and then segmentation is carried out using active contour model. Performance of segmentation is evaluated using dice coefficient and Jaccard coefficient. The nerve location in ultrasound image is detected to help the doctors in giving regional anesthesia. © 2020 IEEE.Item Investigation on Hybrid Polyester Composite Comprising of Sisal and Coir as a Reinforcement and Fly Ash as Filler(Springer Science and Business Media Deutschland GmbH, 2021) Darshan, M.L.; Biradar, S.; Ravishankar, K.S.The use of lignocellulosic fibers such as coir and sisal as reinforcements in thermoplastic and thermosetting resins for developing new material having property superior than the existing one. These biofibers have several advantages, such as good strength, flexibility, low densities, low cost, and biodegradability; over synthetic fibers, these natural fibers are made hydrophobic by 8% NaOH treatment. Alkali treatment increases wettability of fibers with resin and interfacial bond strength. This paper is highlighting about the preparation of hybrid composite and testing the prepared samples for various mechanical and tribological tests such as tensile, flexural, and slurry erosion tests conducted for coir/sisal-hybrid fibers with fly ash as a filler in unsaturated polyester resin. The obtained results are further justified by the SEM images of tested samples from different mechanical tests. This material has been used for automobile application and packing material, roofing material in construction technology. © 2021, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.Item Tribo-mechanical and physical characterization of filament wound glass/epoxy composites(Institute of Physics Publishing helen.craven@iop.org, 2019) Biradar, S.; Joladarashi, S.; Kulkarni, S.M.The present research aims to investigate mechanical, physical and tribological properties of filament wound Glass Fibre Reinforced Polymer (GFRP) composite pressure vessel as per respective ASTM standards. Here test coupons prepared from GFRP vessel are subjected to tensile, compression, flexural and impact testing to investigate mechanical properties. The physical properties are studied from density, ignition loss and water absorption tests. The tribological study was carried out using abrasive slurry erosion tester. All tests carried out in this study are as per respective ASTM standard. The results obtained from various mechanical testings are satisfactory and also almost equal in strength with respect to metallic pressure vessels. Particularly from impact testing, the strength of sea water treated sample has considerably increased. Fractography study was conducted on failed samples to study various mode of failure in detail. The physical characterization has elaborated the behavior of filament wound GFRP material under moisture environment which has observed a maximum of 0.5% water absorption rate. As per ignition loss study which reveals about 95%-98% weight of ignition loss is recorded, which indicates perfect fibre to resin ratio and almost nil or least % of void content. The slurry erosion test results are within the expected range and maximum wear of 9.67% is recorded under extreme case. The overall study reveals that the presence of voids, non-uniform distribution of fibre and matrix have an impact on the outcomes of many mechanical properties. From the above study we can conclude that filament wound GFRP pressure vessel can be used in many applications since it is a non-hydrophobic, better wear resistant and several strength parameters have also improved or unaltered under rigorous testing conditions. © 2019 IOP Publishing Ltd.Item The influence of hygrothermal aging on the hoop tensile strength of glass fiber wound polymer composites fabricated via filament winding technique(Institute of Physics, 2024) Biradar, S.; Hiremath, S.; Vishwanatha, H.M.; Joladarashi, S.; Kulkarni, S.M.The study investigates the impact of moisture environment treatment, on the hoop tensile strength (HTS) of glass fiber-reinforced polymer (GFRP) composites, through hygrothermal aging. GFRP cylinders were fabricated with varied parameters—volume fraction, winding angle, and stacking sequences using a filament winding machine. The fabricated samples are subjected to hygrothermal aging using seawater and tap water with oil at 80 °C for 1080 h (45 days). The HTS tests were performed on unaged and aged samples. There was a reduction in HTS for aged samples which is attributed to heat, seawater contamination, and oil. The highest and lowest HTS values recorded are 402.9 MPa and 118.3 MPa for unaged and tap water with oil-aged samples respectively. HTS in aged samples is compared with unaged samples. The study opens up avenues in identifying the best-suitable combination for retaining HTS under various aging conditions. © 2024 The Author(s). Published by IOP Publishing Ltd.Item Effect of alkaline treatment on mechanical properties of natural fiber-reinforced composite(Korean Society of Mechanical Engineers, 2024) Sangamesh, R.; Hiremath, S.; Biradar, S.; Kumar B, S.; Sondar, P.; Vishwanatha, H.M.Natural fiber-reinforced composites are gaining popularity as eco-friendly alternatives to conventional plastics across various industries. This study investigated the fabrication of composites using areca leaves as the reinforcing filler material within an epoxy matrix. The composites were prepared using the hand-layup technique, with different weight fractions of fibers. Before composite fabrication, the areca leaves were treated with NaOH solution. A comprehensive set of tests, including tensile, compression, flexural, impact, and erosion tests, was conducted on these composites to evaluate their mechanical properties. The results showed that untreated composites exhibited superior performance in tensile (39 MPa) and compression tests (59 MPa with 45 % fiber content), while NaOH-treated composites performed better in flexural (64–67 MPa) and impact tests (21 kJ/m2 at higher fiber content). Erosion testing revealed that composites with lower filler concentrations demonstrated improved wear resistance compared to those with higher filler content, with erosion rates significantly influenced by sand concentration and particle size. These findings were supported by fracture surface analysis using scanning electron microscopy (SEM). This study provides valuable insights into the potential of areca leaf-reinforced composites as sustainable materials for various applications. © The Korean Society of Mechanical Engineers and Springer-Verlag GmbH Germany, part of Springer Nature 2024.Item Mode-I fracture behaviour of aramid/glass-epoxy interply hybrid composites(SAGE Publications Ltd, 2025) Kanakannavar, S.; Biradar, S.; Hiremath, S.; Rajole, S.; Pitchaimani, J.; Kulkarni, S.M.; Goh, K.-L.This article presents the influence of hybridisation of aramid and glass fibre woven fabric on fracture toughness (KIC) of the composites. Experiments using single-edge-notched-bending (SENB) were conducted to investigate the hybridisation effect on the Mode I fracture toughness specimen of aramid/glass laminates. The results revealed that the aramid epoxy composites yielded the highest KIC, followed by aramid/glass epoxy hybrid composites, and finally, glass epoxy composites, which exhibited the lowest KIC. Fracture micrographs of the hybrid composites showed similar fracture patterns – fibre pullout, fibre rupture and matrix rupture – to those of the aramid and glass epoxy composites. The mechanical properties of the hybrid composites being inferior to those of the aramid epoxy composites suggest that there is no advantage in using glass fibres to partially replace aramid fibres in achieving hybrid composites. © The Author(s) 2025