Faculty Publications
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Item Physio-mechanical and wear properties of novel jute reinforced natural rubber based flexible composite(Institute of Physics Publishing helen.craven@iop.org, 2019) Mahesh, V.; Joladarashi, S.; Kulkarni, S.M.This paper deals with the design, fabrication, physio-mechanical and wear characterization of the composites prepared from naturally available jute fiber and rubber matrix materials. Jute and natural rubber are cost effective, abundant and environmental friendly materials which can be used as fiber and matrix respectively. The flexible composite with different stacking sequence are manufactured using compression moulding machine and void percentage, water absorption percentage, tensile properties, tear strength, impact strength and shore hardness of the prepared composites are found along with the wear. The void content and water absorption are found to increase with increased number of plies in the composite with fibers contributing more compared to rubber. Tensile, tear, specific wear rate and hardness are found to better with a composite having minimum number of plies, which is JRJ. Charpy impact test revealed that the variation in specific impact strength of the three configuration of composites are negligible and no failure of composites were absorbed owing to their flexibility indicating all the three composites have additional capability to absorb much higher energy and suitable as sacrificial components for structural applications subjected to low velocity impact. The fractography analysis of tensile and tear test shows that the flexible composites are free from matrix cracking, but matrix tearing plays a vital role in failure. The mechanism of wear involved in the proposed composites when different constituents of the composite are exposed to abrasive medium is studied through surface morphology. © 2019 IOP Publishing Ltd.Item Influence of additives on the synthesis of carbonyl iron suspension on rheological and sedimentation properties of magnetorheological (MR) fluids(Institute of Physics Publishing helen.craven@iop.org, 2019) Aruna, M.N.; Rahman, M.R.; Joladarashi, S.; Kumar, H.Magnetorheological (MR) fluid is one of the major constituent element in structural suspensions and damping characteristic in automobile applications. The major drawback is sedimentation in MR fluids, in the present study an attempt has been done to address the sedimentation issue. The synthesis and characterization of MR fluid in combination with clay and additives leads to improvement in sedimentation rate. The four different types of MR fluid were prepared in combination with clay, friction reducing agent and poly-alpha-olefin (PAO) oil naming as MRFp-1, 2, 3 and 4 as tabulated in table 1. The cost effective MRFp-3 shows better result compared to commercially available MR fluid with respect to off/on state shear stress, viscosity. It is also observed that in-house prepared MRFp-3 has better sedimentation than commercially available (LORD-132DG) up to 700 h. © 2019 IOP Publishing Ltd.Item Design and fabrication of optimized magnetic roller for permanent roll magnetic separator (PRMS): Finite element method magnetics (FEMM) approach(Elsevier B.V., 2021) Mohanraj, G.T.; Rahman, M.R.; Joladarashi, S.; Hanumanthappa, H.; Shanmugam, B.K.; Vardhan, H.; Rabbani, S.A.In the present work, an attempt has been made to develop a PRMS in a cost effective and environmental friendly way through FEMM analysis of magnetic roller (active part of PRMS). The FEMM analysis indicates that, the optimized magnetic roller having magnet-to-steel disk thickness ratio of 5 mm: 2.5 mm was proved to be gainful in beneficiating paramagnetic minerals due to the best magnetic field value from the roller surface that is, 0.89 to 2.59 T. Prediction analysis was performed on FEMM data using artificial neural network (ANN) modelling technique. Further, the design calculations of lab scale PRMS in terms of power requirements and belt tensions were addressed. The fabricated PRMS was tested on paramagnetic mineral (hematite ore) assayed 51.24% of Fe, 10.20% of SiO2, and 2.98% of Al2O3 for different roller speeds and the belt thickness. The result showed that, at 0.5 mm belt thickness with 180 rpm roller speed the fabricated lab scale PRMS works well in terms of improvement in the Fe content up to 59.5% at the concentrate along with the Fe recovery of 71.41%. The obtained results suggest that, the FEMM analysis is more suitable to optimize the effective magnetic roller for the PRMS. © 2021 The Society of Powder Technology JapanItem Real-time testing and thermal characterization of a cost-effective magneto-rheological (MR) damper for four-wheeler application(Springer Science and Business Media Deutschland GmbH, 2023) Jamadar, M.E.H.; Devikiran, P.; Desai, R.M.; Kumar, H.; Joladarashi, S.Recent studies show that the Magento-Rheological (MR) dampers can serve as a suitable replacement for passive dampers on ground vehicles. MR dampers are factory fitted in premium luxury vehicles. However, the high price of these MR dampers has restricted their use to premium vehicles only. The study presented in this article attempts to develop a MR damper, in collaboration with a shock absorber manufacturer, that can replace the existing passive dampers on a passenger van while being more affordable than the commercially available MR dampers. The developed MR damper is subjected to rigorous testing on the damper testing machine to evaluate its damping performance, reliability and thermal performance. The simulation results of the test vehicle model revealed a superior MR damper performance compared to the stock passive damper. The MR damper is later installed on the test vehicle to conduct real-time experiments. The real-time experiments showed that the developed MR damper improved the ride comfort of the test vehicle by 16.2% at 10 km/hr and by 17.6% at 20 km/hr compared to passive dampers while running over a speed bump. The road handling also improved by 14.32% at 10 km/hr and by 29.3% at 20 km/hr. At the end of the study, the cost evaluation performed on the developed MR damper revealed that it was more affordable than the commercially available MR dampers. © 2023, The Author(s), under exclusive licence to The Brazilian Society of Mechanical Sciences and Engineering.Item Optimization and experimental analysis of a cost-effective magneto-rheological (MR) fluid for application in semiactive suspension of a passenger van(SAGE Publications Ltd, 2024) Jamadar, M.E.H.; Devikiran, P.; Kumar, H.; Joladarashi, S.The study presented in this article attempts to determine the optimal composition of iron particles in the MR fluid for vehicular application based on the size of the particles, the simulation response of a test vehicle model, and the cost of the fluid. The MRF samples with two different-sized particles in varying compositions are prepared and characterized on a rheometer. The performance of each MRF sample in the semiactive suspension of a test vehicle is determined by simulating its full car model on a random road. The response of the vehicle model during simulation, the size of the particles, the volume fraction of the particles in the carrier fluid, and the fluid’s calculated cost are input for the Response surface optimization technique. The optimization results revealed that the MR fluid with large-sized particles in a 25% volume fraction would be suitable for the said application. Moreover, it was found that the rheological performance of the optimized MR fluid was better than the commercial MR fluid. The performance of the optimized fluid in a MR damper was experimentally evaluated against the stock passive damper of the test vehicle. The results of the experiment on the test vehicle showed that the MR damper improved the test vehicle’s ride comfort by 36.58% over a speed bump and 11.3% on an off-road test track. The road handling was also improved by 45% over a speed bump and 46% over the test track. © IMechE 2023.