Faculty Publications
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Item Heterogeneous locational optimisation using a generalised Voronoi partition(2013) Guruprasad, K.R.; Ghose, D.In this paper a generalisation of the Voronoi partition is used for locational optimisation of facilities having different service capabilities and limited range or reach. The facilities can be stationary, such as base stations in a cellular network, hospitals, schools, etc., or mobile units, such as multiple unmanned aerial vehicles, automated guided vehicles, etc., carrying sensors, or mobile units carrying relief personnel and materials. An objective function for optimal deployment of the facilities is formulated, and its critical points are determined. The locally optimal deployment is shown to be a generalised centroidal Voronoi configuration in which the facilities are located at the centroids of the corresponding generalised Voronoi cells. The problem is formulated for more general mobile facilities, and formal results on the stability, convergence and spatial distribution of the proposed control laws responsible for the motion of the agents carrying facilities, under some constraints on the agents speed and limit on the sensor range, are provided. The theoretical results are supported with illustrative simulation results. © 2013 Taylor & Francis Group, LLC.Item Multi-response optimisation of surface texturing using artificial bee colony algorithm(Inderscience Publishers, 2016) Chakraborty, S.; Chakraborty, R.; Nagendrababu, K.; Talla, G.; Gangopadhyay, S.Determination of the optimal combination of process parameters plays a pivotal role in reducing manufacturing costs while enhancing rate of productivity and standard of quality of the product. This paper deals with fabrication of arrayed structures consisting of cylindrical pillars using reverse electro discharge machining (R-EDM) process, followed by optimisation of the process using artificial bee colony (ABC) algorithm. The influence of various machining parameters such as peak current (Ip), pulse-on time (Ton) and flushing pressure (Fp) on multiple performance measures in R-EDM like material removal rate (MRR), surface roughness (SR), taper and cylindricity error (CE) has been investigated using response surface methodology (RSM) based approach. In the course of this paper, the optimal parameters have been found to be Ip = 10 A; Ton = 179.091 ?s; Fp = 0.2 kg/cm2. The fast convergence and the high degree of closeness with the experimental data under optimal condition establishes the efficiency and robustness of the algorithm. © © 2016 Inderscience Enterprises Ltd.Item Multi-objective optimisation of cryogenic turning process using Taguchi-based grey relational analysis(Inderscience Publishers, 2017) Sivaiah, P.; Dupadu, D.Cryogenic machining is a sustainable manufacturing approach; it eliminates coolant disposal cost, health problems compared to the conventional flood cooling. The present study investigates the multiple response optimisation of turning process while machining AISI 17-4 PH stainless steel under the cryogenic environment (jetting of liquid nitrogen at -196°C at the rake face of the tool) by using Taguchi-based grey relational analysis. The optimum levels of the machining parameters are cutting speed at 120.89 m/min, feed rate at 0.048 mm/rev, depth of cut 0.4 mm and physical vapour deposition (PVD) AlTiN coated tungsten carbide (WC). Taguchi-based grey relational analysis method reduced the cutting forces by 7.75%, improved the surface finish by 55.87%, and increased the material removal rate (MRR) by 154.76% and 25% increased the tool flank wear in cryogenic turning process. From the analysis of variance, it was identified that feed rate is the most influenced process parameter on turning performance characteristics. © © 2017 Inderscience Enterprises Ltd.Item Optimization of Fenton’s oxidation of herbicide dicamba in water using response surface methodology(Springer Verlag, 2017) Sangami, S.; Manu, B.In this study Fenton’s oxidation of dicamba in aqueous medium was investigated by using the response surface methodology. The influence of H2O2/COD (A), H2O2/Fe2+ (B), pH (C) and reaction time (D) as independent variables were studied on two responses (COD and dicamba removal efficiency). The dosage of H2O2 (5.35–17.4 mM) and Fe2+ (0.09–2.13 mM) were varied and optimum percentage removal of dicamba of 84.01% with H2O2 and Fe2+ dosage of 11.38 and 0.33 mM respectively. The whole oxidation process was monitored by high performance liquid chromatography (HPLC) along with liquid chromatography/mass spectrometry (LC/MS). It was found that 82% of dicamba was mineralized to oxalic acid, chloride ion, CO2 and H2O, which was confirmed with COD removal of 81.53%. The regression analysis was performed, in which standard deviation (<4%), coefficient of variation (<8), F value (Fisher’s Test) (>2.74), coefficient of correlation (R2 = Radj2) and adequate precision (>12) were in good agreement with model values. Finally, the treatment process was validated by performing the additional experiments. © 2017, The Author(s).Item Optimum location and influence of tilt angle on performance of solar PV panels(Springer Science and Business Media B.V., 2020) Khan, T.M.; Soudagar, M.E.M.; Kanchan, M.; Afzal, A.; Banapurmath Nagaraj, N.R.; Akram, N.; Mane, S.D.; Shahapurkar, K.With the growing demand of economically feasible, clean, and renewable energy, the use of solar photovoltaic (PV) systems is increasing. The PV panel performance to generate electrical energy depends on many factors among which tilt angle is also a crucial one. Among hundreds of research work performed pertinent to solar PV panels performance, this work critically reviews the role of tilt angles and particularly locating the optimum tilt angle using different methods. The past data collected for analysis can be categorized mainly into mathematical model based, experimental based, simulation based, or combination of any of these. Single-axis tracking, dual-axis tracking, simple glass cover, hydrophobic glass cover, soiled glass, clean glass, partial shadow, use of phase-change material, computational fluid dynamic analysis, etc., are the novel methods found in the literature for analysis and locating the optimum tilt angle. For illustration purpose, few figures are provided in which the optimum tilt angle obtained on monthly, seasonally, and annual basis is shown. Research works are growing in the field of computations and simulations using online software and codes. Pure mathematical-based calculations are also reported but the trend is to combine this method with the simulation method. As the PV panel performance is found to be affected by number of parameters, their consideration in any single study is not reported. In future, work is required to carry out the experiment or simulation considering the effect of soiling, glass material, temperature, and surrounding ambience on the location of optimum tilt angle. As a whole, the optimum tilt angles reported for locations exactly on the equator line, i.e., 0° latitude, ranges between ? 2.5° and 2.5°, for locations just above the equator line, i.e., latitude 2.6°–30° N ranges between 5° and 28°, for 40°–70° N, it is 29°–40°, and for 71°–90° N, it is 41°–45°. For locations at 2.6°–30° S, optimum tilt angles range between ? 4° and ? 32°, 30°–46° S, it is ? 33° to ? 36°, 47°–65° S, it is ? 34° to ? 50°, and for 66°–90° S it is ? 51° to ? 62°. © 2019, Akadémiai Kiadó, Budapest, Hungary.Item Mathematical modeling and optimization of tribological behaviour of Al 7075 based hybrid nanocomposites(SAGE Publications Ltd, 2021) Kannan, C.; Radhakrishnan, R.; Balan, A.S.S.Many industrial applications necessitate lightweight materials that possess better tribological behaviour. Whilst aluminium based nanocomposites are proposed owing to their lightness, their tribological characteristics must be improved which are dominantly influenced by the selection of reinforcements, manufacturing process and heat treatments. In this research, an aluminium hybrid nanocomposite is produced using a novel molten salt processing and subjected to different heat treatments. Their tribological behaviour is assessed under different operating conditions viz. load, sliding velocity and material condition of the pin. Regression models are formulated to predict the tribological behaviour of developed hybrid composite under different heat treatments. The most significant parameter and optimum level for each of these operating parameters are determined using analysis of variance, main and interaction plots and response surface methodology in the end. The integrated approach helps in deciding the optimum parameter setting for the development of nanocomposite with ameliorated tribological behaviour. Under the optimized conditions, the hybrid nanocomposite could able to reduce the wear resistance by about 63% and the coefficient of friction by 18.5% than unreinforced alloy. © IMechE 2020.Item Experimental assessment of FSW process to join AA6061/Rutile composite and parametric optimization using TGRA(IOP Publishing Ltd, 2021) Prabhu B, S.R.; Shettigar, A.; Herbert, M.A.; Rao, S.S.Present study is focused on investigating the effect of various friction stir welding (FSW) process variables on AA6061/Rutile composites welding quality. FSWof composites was performed considering tool geometry (Tg), welding speed (Ws) and rotational speed (Ns) as ideal parameters for multi-response optimization. Experiments were designed based on the L9 orthogonal array. Analysis of variance (ANOVA) was utilized to evaluate the effects of these welding process variables on output responses namely hardness and ultimate tensile strength (UTS). Main effects plots were drawn to found out the optimal levels of these process parameters. Multi-response optimization of the welding process has been performed using Taguchi's grey relational analysis (TGRA). Analysis revealed that welding speed of 90mmmin-1, a tool with a square pin, and rotational speed of 1000 rpm produced an FSWjoint with excellent mechanical properties. Microstructure analysis revealed that refinement in the grain structure and redistribution of reinforced particles helped in improved joint strength. © 2021 IOP Publishing Ltd.Item Control and dynamic optimization of middle vessel batch distillation column for the separation of ethanol/propanol/butanol mixture(Institution of Chemical Engineers, 2021) Krishna, P.; Desikan, B.; Sankar Rao, C.The middle vessel batch distillation column is an alternative to the regular batch distillation column. This configuration allows simultaneous separation of the light fraction (accumulated at top), heavy fraction (accumulated at bottom) and the intermediate fraction (accumulated in the middle vessel) in a single column. The objective of this article is to extensively analyse and discuss different control systems for the middle vessel batch distillation column (MVBDC) and dynamically optimize the column. Three control structures such as composition level cascade, composition temperature cascade, and temperature control system, have been tested and evaluated. Further, a dynamic optimization study has been performed on the control system providing the fastest separation. The optimizer is set to minimize the total energy consumed during the process. This resulted in a decrease in batch time from 26.8 to 25.2 h and a 13.5% decrease in overall energy usage. The presented dynamic optimization technique and control system design is useful for improving the performance of the MVBDC. © 2021 Institution of Chemical EngineersItem Exergoeconomic Optimization of Low Temperature Solar Driven Organic Rankine Cycle(Pleiades journals, 2021) Upadhyaya, S.; Gumtapure, V.Abstract: One of the most promising technologies in the field of distributed energy is the use of installations operating on the so-called organic Rankine cycle (ORC). The ORC technology is applicable for the utilization of low-potential thermal energy of natural or man-made origin. At the same time, in each specific case of using ORC systems, it is important to carry out technical and economic optimization of the project. In this paper, it is proposed to estimate the cost of electricity production by an ORC power unit using an exergoeconomical model. To optimize the system parameters in order to minimize the electricity cost rate, the method of a genetic algorithm is used. The paper presents the results of optimization of the parameters of the ORC system, which includes a solar collector in combination with an ORC power unit. R245fa is used as the working fluid in this analysis. With the help of a mathematical model, the electricity cost is calculated by comparing the costs for each of the components of the ORC system. For a given operating range of parameters of an ORC power unit with an electric capacity of 1.03 kW, a minimum cost rate of $0.056/(kW h) is determined. The optimal parameters of the working fluid in the ORC power unit, at which the minimum electricity cost can be obtained, are also determined. © 2021, Pleiades Publishing, Inc.Item Investigation on the operational parameters of screening coal in the vibrating screen using Taguchi L27 technique(Taylor and Francis Ltd., 2022) Shanmugam, B.K.; Vardhan, H.; Raj, M.G.; Kaza, M.; Sah, R.; Hanumanthappa, H.In the present work, optimization of the newly developed vibrating screen’s operational parameters was carried out to obtain a high response parameter. The operational parameters considered in the present work were moisture content, angle, and frequency. The Taguchi L27 design technique was used to optimize three different operational parameters to obtain high screening efficiency of coal in the vibrating screen. The maximization of screening efficiency was obtained by selecting the “larger the better” condition for developing the model. The regression coefficient of 99.6% shows the close relationship between the predicted and experimental values. The lower value mean error and standard deviation of normal probability indicate that the developed model has less error. From the optimization results, it was clear that the 4% moisture content (low level), 1-degree angle (low level), and 9 Hz frequency (medium level) yielded high screening efficiency. Further, a confirmation test was carried out with the optimized condition, which has yielded a screening efficiency of 84.40%. The results showed that the Taguchi technique could be applied to study the influential operational parameters for maximizing the vibrating screen efficiency. © 2021 Taylor & Francis Group, LLC.