Faculty Publications
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Item Enhancing the Dewatering Ability of Sludge by Locally Available Biomass(Springer Nature, 2023) Chopade, G.; Devatha, C.P.In this study, the effect of modified coconut shell biochar is analyzed for its efficacy achievable in sludge dewatering properties. Initially the coconut shell biochar is modified at different molar concentrations of FeCl3, i.e., 1, 2, and up to 5 mol/L, and it is analyzed with different dosages at 0.1, 0.2, and up to 0.4 (g/g of dry solids (DS)) for the improvement in capillary suction time (CST) (s), moisture content reduction (%), filterability (min), and settleability (SV30%) of the sludge. It is found that there is significant decrease in each of these parameters. The optimization study is carried out to optimize the process of sludge conditioning, considering independent regression parameters as dosage (g/g of DS), molarity (M), mixing time (min), and response taken as moisture content (%), the optimum values for the dosage, molarity, mixing time is found to be 0.4 (g/g of DS), 2.5 M and 24.72 min, respectively, with optimized moisture content value of 78% was achieved. Hence, the modified coconut shell biochar can be used as a potential candidate to increase the dewatering ability of the sludge. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2023.Item Experimental investigations on hole quality in drilling of cenosphere reinforced epoxy composite(Institute of Physics Publishing helen.craven@iop.org, 2019) Angadi, S.B.; Ashrith, H.S.; Gaitonde, V.N.; Karnik, S.R.; Doddamani, M.Cenosphere reinforced epoxy composites are steadily replacing the conventional materials in marine, aerospace and automobile structuresowing to their lightweight properties.Drilling is an important conventional machining process essential for assemblyof polymer composites using rivets and bolts. Drilling induces damage around the hole which significantly deteriorates composite performance. In the present study, hole quality characteristicssuch as cylindricity and delamination in drilling of fly ash cenosphere filled epoxy composites are investigated using coated tungsten carbide drill bits.Feed, cutting speed, filler content and drill diameter are considered as the drilling process variables.Samples are fabricated by varying cenosphere content from 10to 60by volume %inepoxy resin.Full factorial design (FFD) based experiments are conducted on CNC vertical machining center. Response surface methodology (RSM) based mathematical models are proposed to estimate the characteristics of the hole quality in developed composites. Analysis of variance is used to validate the developed mathematical models.Present study reveals that the cylindricity and delamination decreases with increasing feed. Increasing cutting speed decreases the cylindricity, however delamination is found to be increasing.Results also shows the importance of using high cenosphere content for producing sound quality holes, which is also beneficial from weight savingperspective. © 2019 IOP Publishing Ltd. All rights reserved.Item Optimal Parameters Identification of Quarter Car Simulink Model for Better Ride Comfort and Road Holding(Springer Science and Business Media Deutschland GmbH, 2021) Puneet, P.; Hegale, A.; Kumar, H.; Gangadharan, K.V.Advancement in vehicle technology has explored many possibilities for improvement, keeping customer satisfaction in mind. One major criterion which a passenger always wishes to possess is ride comfort. But the suspension parameters suitable for a good ride comfort may not support another salient feature called road holding. Hence, in this work an attempt has been made to simultaneously improve the ride comfort and road holding, using a quarter car test model using MATLAB Simulink for a commercial light motor vehicle. Initially, a commercially available passive damper of light motor vehicle has been characterized using dynamic testing machine (DTM) in order to obtain its force–displacement behavior and damping nature. A design of experiment (DOE) has been conducted by taking vehicle velocity, sprung mass, spring stiffness and damping coefficient into consideration, for experimentation using quarter car model. Regression equations have been extracted for relating the problem parameters to both ride comfort and road holding. Analysis of variance (ANOVA) has been used to know the influence of each parameter toward the target response. In the later stage, response surface methodology optimization technique has been used in order to optimize the parameters for better ride comfort and road holding. Optimized parameters are substituted again in the quarter car model, to validate the results obtained during optimization. The present work concluded with an optimal ride comfort and road holding and proved the effectiveness of optimization technique in achieving so. © 2021, The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.Item Modelling of squeeze casting process using design of experiments and response surface methodology(Maney Publishing maney@maney.co.uk, 2015) Gowdru Chandrashekarappa, M.; Krishna, P.; Parappagoudar, M.B.The present work makes an attempt to model and analyse squeeze casting process by utilising design of experiments and response surface methodology. The input–output data for developing regression models and test cases is obtained by conducting the experiments. Surface roughness, ultimate tensile strength and yield strength have been measured for different combinations of process variables, namely, squeeze pressure, pressure duration, pouring temperature and die temperature. Two non-linear regression models based on central composite design (CCD) and Box-Behnken design (BBD) of experiments have been developed to establish the input–output relationships. The effects of process variables on the measured responses have been studied using surface plots. The performances of the two non-linear models have been tested for their prediction accuracy with the help of 15 test cases. It is observed that, both CCD and BBD, the non-linear regression models are statistically adequate and capable of making accurate predictions. © 2015 W. S. Maney & Son Ltd.Item Isolation of Novel Aerobic denitrifier and optimization of process parameters for biological denitrification using RSM(Slovak University of Agriculture info@jmbfs.org, 2019) Joshi, K.; Navalgund, N.; Shet, V.B.; Srinikethan, G.; Ashwini; Sneha; Anusha; Aparna, A.The study aimed to isolate and characterize a high efficiency novel bacterium for denitrification in waste water and also to optimize process parameters under aerobic condition. One of the bacteria chosen among four, displayed a maximum of 98% reduction of nitrate. The strain was identified as Enterobacter sp. NCCP-29 by biochemical tests and further identified based on similarity of PCR-16S rRNA using universal primers. The parameters (pH, temperature, agitation speed, C:N ratio) which effect the denitrification were screened using one factor at a time. The pH, temperature and C:N ratio exhibited significant effect on the denitrification using Enterobacter sp. NCCP-29. The levels of these parameters were optimized using a central composite design (CCD). A maximum of 98% denitrification was achieved at pH 6.5, temperature 30°C and C: N ratio of 3:1. The second order model was generated and found to have a good fit with R2 value of 0.93. Investigations revealed the ability of Enterobacter sp. NCCP-29 to remove nitrate under aerobic conditions. © 2019, Slovak University of Agriculture.Item Generation of microholes on GFRP composite using ES-µ-ECDM system(Elsevier Ltd, 2022) Bhargav, K.V.J.; Shanthan, P.; Balaji, P.S.; Sahu, R.K.; Sahoo, S.K.Microfeatures fabrication on FRPs is very essential nowadays because of its growing demand in various industries like aerospace, automobile, space, marine, etc. Glass fiber reinforced plastic (GFRP) composite is one among the FRPs that has many potential applications with extraordinary physical, chemical and mechanical properties. Generation of microholes on GFRP composite has gained its pace in recent years because of its applications in circuit boards and filters in biomedical applications. This study focuses on the generation of microholes in GFRP composite using an in-house developed electrolyte-sonicated micro-electrochemical discharge machining (ES-µ-ECDM) system. The process parameters voltage (V), concentration (wt%), and feed rate (µm/s) are selected at three levels for performing experiments using FCC-RSM modeling. The machining responses material removal rate (MRR) and overcut (OC) are analyzed. A RSM-based regression model is developed, and a multi-objective optimization using the MOJAYA algorithm is employed to obtain a set of non-dominated Pareto optimal solutions. The Pareto optimal solution set showed a feed rate of 5 µm/s should be employed for better MRR and OC. The SEM micrographs have shown a feed rate of 5 µm/s produced smooth surfaces at voltages and concentrations less than 55 V and 17.5 wt%, respectively. © 2022 Elsevier LtdItem Study and Experimental Investigation of the Effect of Progressive Feed Rate on Surface Roughness in CNC End Milling Process Using RSM(International Information and Engineering Technology Association, 2022) Bommisetty, S.R.; Chettu, K.B.; Hanumanthappa, S.N.The objective of this research work is to investigate the influence of cutting parameters on the average surface roughness (Ra) in an end milling process. Feed rate if). Spindle speed (s) and Depth of cut (d) are the cutting parameters considered as significant factors. A case study on the progressive feed (PF) and conventional constant feed (CF) machining characteristics of Aluminum alloy BS L168-T6511 using end milling is considered. Taguchi's design of experiments (DoE) technique is applied for various combinations of cutting factors and average surface roughness was measured using Mitutoyo surftest SJ-301 surface roughness tester. The experimental results of Ra are analyzed by response surface methodology (RSM). The predicted values using the developed regression mathematical model are compared against experimental results and were found in close agreement. ANOVA technique was applied to further analyze the data for checking the model adequacy and to predict the influence of each parameter on output response Ra. Main effect plots. Interaction plots. 3D surface plots, and Contour plots are established. The investigation reveals that output response (Ra) is predominantly affected by feed rate and progressive feed machining (PFM) yields better surface finish than the conventional constant feed machining (CFM) for the end milling. © 2022 Lavoisier. All rights reserved.