Advances in Applied Mechanical Engineering

In this present study, the effect of heat spreader in a horizontal channel consisting of electronic chips with mixed convection and surface radiation is examined. SIMPLER algorithm with finite volume method is used to solve governing equations using ANSYS 16.2 software. Results show the increase in the performance of heat transfer with an increase in the values of governing parameters like Reynolds number and emissivity of the spreader.

The sequence of hybrid rocket motor static firings is performed, with and without cylindrical protrusion, to evaluate the combustion behavior of bee-wax fuel grain. Firing is done for the injection pressures of 2.75 bar, 4.15 bar, and 5.51 bar, respectively, all firings are done for an identical firing duration of 7 seconds. Experimental outcome confirms the addition cylindrical protrusion as vortex generator yield an average of 45% higher regression rate than that of the baseline rocket motor. Among all injection pressures, modest 4.15 bar with cylindrical protrusion shows a significant improvement in the combustion performance by exhibiting the enhanced regression rate as well as mass consumption rate of the fuel grain. Hence, the addition of cylindrical protrusion as a vortex generator to the classical hybrid motor promise to improve the combustion performance of the bee-wax fuel grain.

In India, farmers depend on variable rainfall and groundwater for irrigation. Load shedding and high diesel cost are the barriers for regular watering of crops. Solar photovoltaic water pumping system (SPVWPS) is a better sustainable option, but the high capital cost is hindering widespread applications. The Maharashtra state government distributed SPVWPS to marginal farmers (Whose land holding is less than 5 acres) and are grid isolated, providing subsidies as high as 95%. Total, 8959 pumps are distributed till November 2018 in the whole Maharashtra state with 210 in Nagpur district only. Current work assesses the impact of the use of SPVWPS on the livelihoods of farmers, their social and economic condition by conducting a survey. The aim of the study is to evaluate the health, reliability and durability of SPVWPS. An effort has been made to understand the grassroots level insights associated with solar pump use. The field research was carried on by interviewing farmers. Questionnaires were created in order to get useful data required easily. By splitting up the questionnaires into different areas, the results gave a general impression of the farmer’s daily challenges and troubles. The authors surveyed total 25 sites from 17 villages of 8 Talukas of Nagpur district. Payback period value of solar pump is calculated with respect to electric and diesel pump using breakeven point analysis and found that shifting from diesel to solar pump have shorter payback period.

The present investigation has been undertaken to assess the effect of axial conduction and viscous dissipation on heat transfer characteristics in the thermally developing region of a parallel plate channel with porous insert attached to both the walls of the channel. Both the walls are kept at uniform heat flux. The fully developed flow field in the porous region corresponds to Darcy–Brinkman equation and the clear fluid region to that of plane Poiseuille flow. The effect of parameters, Brinkman number, Br, Darcy number, Da, Peclet number, Pe, and a porous fraction, γp have been studied. The numerical solutions have been obtained for, 0.005 ≤ Da ≤ 1.0, 0 ≤ γp ≤ 1.0 and −1.0 ≤ Br ≤ 1.0 and Pe = 5, 25, 50, 100 and neglecting axial conduction (designated by Ac = 0) by using the numerical scheme successive accelerated replacement (SAR). There is an unbounded swing in the local Nusselt number because of viscous dissipation.

Thermosyphon is a heat transferring device which transfers heat over long distance and where the liquid is returned to the evaporator by gravitational force. The closed-loop thermosyphon (CLT) transfers heat with phase change phenomenon. A large amount of heat is transferred from evaporator section to condenser section with a relatively small temperature difference. The thermal performance of closed-loop thermosyphon (CLT) is influenced by the governing parameters like filling ratio, heat input, adiabatic length, working fluids, etc. This paper investigates the effects of these parameters on thermal performance of closed-loop thermosyphon system for different working fluids. In this work the filling ratio (FR) is varied in the range of 30–80% in the step of 10% at various heat inputs of 0.5–2 kW with a step of 0.5 kW for each evaporator and adiabatic length (vapor line length) is taken as 200 mm. The working fluid used as methanol, ethanol, acetone, and distilled water. The performance plots of the performance parameters like thermal resistance, evaporative heat transfer coefficient (HTC), and condenser heat transfer coefficient for these different working fluids, heat inputs, and filling ratios are plotted and results are analyzed. From the result, it is found that acetone has comparatively lowest thermal resistance. Water has comparatively highest evaporative heat transfer coefficient as well as condenser heat transfer coefficient.

Computational studies incur engineering costs. While direct numerical simulations can provide detailed solutions, they cannot deliver quick and convenient solutions which are pragmatic for industry applications such as fault detection and diagnosis. But in the study of internal combustion engines, there are no such unified models that can completely capture the engine operation and hence, computational methods still are of great value. In this pursuit, an attempt had been made in this study to evaluate the empirical redundancy amongst the engine variables. Using Pearson correlation coefficient to quantify the linear dependencies among a set of variables, a representation score was developed to measure how effectively various variables can represent other variables. With the suggested methodology, those empirically important variables can be identified and they can be used to develop empirically reduced models for its possible employment in further computational studies.

Numerical analysis of mixed convection with surface radiation on a vertical channel is conducted. Five protruding heat sources are mounted on the left wall of the channel, and copper heat spreader is attached upon each heat source. Governing equations are solved using SIMPLER algorithm in ANSYS 16.2 software. Results are presented to depict the effects of parameters like heat spreader width (Ws = W − 2W), emissivity of heat spreader (εsp = 0.1–0.9) and Reynolds number (Re 250–750) on the rate of heat transfer by fixing emissivity of heat source and substrate. It is found that with increasing spreader width and emissivity, heat transfer performance increases.

Heat transfer enhancement and hence performance of solar air heaters can be improved by absorbing maximum amount of solar insolation. Absorption rate in solar air heater is increased when it is oriented all the time in perpendicular direction to solar insolation. Hence, inclination of solar air heater along with other geometrical and operating parameters plays an important role to decide its thermal performance. In the present work, a double-pass packed bed solar air heater is experimentally tested to know the effect of its inclination to solar insolation on its thermal performance. Experiments are conducted at different mass flow rate of air in the range of 0.038–0.0508 kg/s and at different inclination of solar air heater in the range of 5°–25° to the horizontal surface. It was found that efficiency of solar air heater is lower at 5° and 10° inclinations for all mass flow rates of air. Efficiency increased and reaches to its maximum value for 15° and 20° inclinations of the solar air heater, and it decreases with further increase in inclination to 25° at all mass flow rates of air.

In the present study, the surface pressure distribution of an Indian train engine was experimentally investigated. A scaled model of the engine was tested at different Reynolds numbers ranging from 3.22 × 104 to 14.49 × 104. The variation of aerodynamic drag and pressure distribution with Reynolds number were studied. The results show that the pressure distribution is not significantly affected with the Reynolds number and a maximum coefficient of drag of 0.6005 is obtained at a Reynolds number of 6.44 × 104. The mean drag was also calculated for further understanding of drag characteristic of the engine model.

Energy quality can be best measured through the application of the proven method of exergy analysis. Exergy analysis of thermal systems provides a better way to determine the deficient sub-components and also estimate the amount of losses that occurred in such components. The present work models a coal-fired open-cycle Magneto-hydrodynamics (MHD) power generation system in terms of exergy analysis. The exergy analysis is carried out side-to-side energy analysis in order to determine the components with major energy losses and exergy destruction in the modelled plant. It is observed that the nozzle has the maximum energy losses as well as exergy destruction followed by the generator. Energy losses for the compressor, combustor, air preheater, seed recovery unit, sulphur removal unit and the stack showed a higher value of energy losses in comparison to that of exergy destruction values in these components. From the exergy point, it has been found that the components that require most improvement ar×e the nozzle and the generator.

Engines are one of the greatest Mechanical Engineering application developed in 90s. Compression ignition engines are very robust, durable and efficient. The volumetric efficiency of CI engine is higher because of absence of throttle losses in comparison to SI engine. The flow of air through the intake manifold considerably affects the power and volumetric efficiency of CI engines. In present investigation, existing intake manifold of CI engine is modified and manufactured by additive manufacturing technique. The optimized design was finalized by undergoing computational fluid dynamic analysis. The new intake manifold is fitted to the engine intake and performance tests were performed. For all load conditions, the volumetric efficiency, brake power and brake thermal efficiency were considerably improved. The brake specific fuel consumption was also reduced.

The reference wind velocity inside the test section of an open-type subsonic wind tunnel is established from the measurements of dynamic pressure and the average static wall pressure difference between stations at upstream of the test section and at the settling chamber. A wind tunnel calibration factor was obtained which relates the dynamic pressure and thus the wind velocity inside the test section with the average static wall pressure difference at a station near upstream of the test section and at the settling chamber. An average wind tunnel calibration factor was found to be 0.8189. The longitudinal variation of static pressure inside the test section is also obtained using the pitot-static tube.

During past decade, there has been an increasing trend to save the amount of heat energy lost from the steam while carried through pipes. Improper selection of the pipe insulation material leads to the loss of energy and reduces the amount of energy content at the usage point which in turn increases the fuel cost. Hence, there is a need to conserve energy by choosing suitable insulating material. The present paper deals with optimal selection of insulating material based on multi-criteria decision-making analysis using Analytical Hierarchy Process (AHP). Five different criteria (insulating materials) and five alternatives, namely cost, thermal conductivity, flammability, toxicity, and noise are considered for the analysis of decision making in order to choose best insulating material for energy conservation. Ranks are given to the alternatives based on their criteria weights using AHP pairwise comparison matrices. The results indicate that rock wool is the suitable insulating material for the conservation of energy in the steam pipe.

The thermal performance of a heat exchanger can be improved by various techniques. It is a major concern when coming to industries as the heat losses play a major role in efficiency of the overall plant. The present work is carried out to enhance the heat transfer rate of a tubular heat exchanger by incorporating overlapped dual twisted tapes (ODTTs) or inserts into a tube and carrying out the numerical simulation for different twisting ratios of ODTTs. In addition to this, Al2O3 nanoparticles are used as additives to increase the value of heat transfer coefficient (h), thereby improving the Nusselt number (Nu) and overall thermal performance. The addition of ODTTs resulted in improved residence time, more contact surface area and improved fluid mixing and swirling for effective heat transfer to take place. The numerical simulation is repeated for nanofluid concentrations of 1% and 2% and also for varying twisting ratios of Yo/Y = 1.5, 2 and 2.5. The tube with 1% nanofluid concentration and twisting ratio Yo/Y = 2 yielded better results in comparison with all other combinations.

This paper presents the influence of wall contours on a circular cross-section contraction nozzle of compressor intermediate S-shaped duct facility. Flow uniformity and boundary layer development under different wall contours are examined by using numerical simulations. Effect of wall shape on the pressure loss within the contraction is examined, and the maximum difference of pressure loss between the two wall shapes is about 84 Pa. Higher-order equation encounters higher pressure loss due to secondary flow generation and thicker boundary layer development. CT#4 (marched cubic case) shows the minimum value of $$U_{n}$$ and standard deviation at the outlet of contraction which indicates the lowest non-uniformity among all cases.

The researchers focus on eco-friendly and economy of power generation in the thermal power plants. The system-wise analysis will help to find the way to economic power generation. This research focuses the hopper heating concern. Usually, the electric heating is employed to maintaining the hopper as warm to avoid distraction in the flow of ash. The research argues the feasibility of steam heating in the view of waste heat recovery. A new kind of hopper was designed, and its prototype was fabricated, tested and analysed. The qualitative and quantitative benefits of proposed system were discussed. The proposed system, irrespective of climatic changes, works well.

Aircraft propeller performance study is one of the most challenging areas in the aeronautical research field. This paper compares the experimental and theoretical thrust results for various propellers and also provides a methodology for a portable static experimental setup. This will pave the way for propeller design by comparing the thrust values. These data will give more clarity to researchers comparing the experimental and theoretical thrust values of micro-aerial vehicle (MAV) propeller.

Active and passive techniques are generally used by the researchers for the heat transfer augmentation of fluids. Conventional fluids like water, ethylene glycol, and oils have not enough heat transfer capabilities to fulfill current requirements of high heat transfer rates of heat exchangers. Nanofluids are the new-generation fluids that have better heat transfer capabilities over traditional heat transfer fluids. The current study examines heat transfer analysis in a shell and helical tube heat exchanger using Al2O3 nanoparticles in aqueous solution. The analysis was carried out to determine the enhanced heat transfer rate as compared to the base fluid (water) in a vertical shell and helical coil geometry. Four different nanoparticle concentrations—1–4% by volume along with four different mass flow rates vary from 0.03 to 0.113 kg/s—were used to simulate the results. Results showed that the heat transfer rate of nanofluids was enhanced at higher mass flow rates, concentrations, and coil-side inlet temperatures.

The present study discusses the effect of fluid–structure interaction (FSI) in a square cavity with a top wall oscillating, i.e., sinusoidal variation of the velocity of the top wall. Due to this varying motion of the top plate, fin (flexible plate) starts oscillating in the transverse direction of the fin length. Due to flexible plate motion, fluid motion also gets disturbed, and because of this it can increase or decrease the heat transfer rate of the hot wall. For checking the effect of fin, flexible plate is set on the left, right and bottom wall. It is observed that incorporation of flexible flap on any wall decreases the heat transfer rate.

The dimensionless heat transfer parameters such as Nusselt number, Reynolds number and Prandtl number are function of thermophysical properties of the nanofluids and these numbers strongly influence the convective heat transfer coefficient. In thermal systems, the heat transfer coefficient quantifies the rate of heat transfer. The thermophysical properties of the nanofluid vary with particle concentration and temperature. In the present study, experimental analysis has been performed to evaluate the influences of particle concentration and temperature on thermophysical properties of various metal oxide nanofluids. For this study, aluminium oxide (Al2O3), copper oxide (CuO), titanium dioxide (TiO2) and silicon dioxide (SiO2) nanoparticles with de-ionized water are chosen and all the experimental results are compared with pure water. The experimentally measured thermophysical properties of the various nanofluids with the empirical correlations are compared. A considerable deviation is observed between the measured results and the empirical solutions. Finally, from the results it can be concluded that, nanofluids have enhanced thermophysical properties, and they may be considered as a suitable fluid for various heat transfer applications.

Numerical simulations using Euler-Euler model (also known as two-fluid model) were used to predict pressure drop in pneumatic conveying (i.e., gas-solid flows) in vertical pipes. Standard $$k - \varepsilon$$ turbulence model has been used for gas phase, and kinetic theory of granular flows (KTGF) was used to close solid phase stresses and solid pressure aroused due to inter-particle collisions. The model was validated by comparison with the available experimental data and good agreement was found for pressure drop prediction. The effect of important flow parameters like gas phase Reynolds number, solid loading ratio and particle density on pressure drop was investigated. It was observed that pressured drop increased with gas velocity and solid loading ratio. Finally, computed results for pressure drop are compared with the existing correlations. Present predictions showed good agreement with the correlations of (Reddy and Pei in Ind Eng Chem Fundam 8:490–497, 1969 [1], Capes and Nakamura in Can J Chem Eng 51:31–38, 1973 [2]) data.

The CFD analysis for design of diffuser for air cooling of low-concentrated photovoltaic (PV) solar collector is carried out. PV panel is made up of silicon, a semiconductor, which have the capacity to convert dispersed as well as concentrated solar radiation into electricity directly. The problem encountered with silicon PV panel is overheating due to excessive solar radiation and high ambient temperature. Overheating drastically lowers the efficiency of solar panel. The proper cooling system is required to remove excessive heat and to increase the efficiency of PV panel. One method of cooling PV panel is the supply of uniformly distributed air along the panel. The diffuser is used for uniform distribution of air. Different shapes of diffusers with and without deflector plates are analysed for uniform distribution of air using commercial software ANSYS FLUENT. The CFD analysis revealed that the diffuser with curved sidewalls and deflector plates distribute the air more uniformly than the diffuser with straight sidewalls.

Computational fluid dynamics (CFD) analysis of circular diffuser with flange is carried in present analysis using ANSYS CFD tool. A wind turbine with circular diffuser and flange attached over the periphery of the diffuser is simulated for various flange angle range of 0°–25°. Provision of diffuser has demonstrated significant augmentation in power and speed of the turbine. The study also shows that the variation of flange angle creates strong vortices behind the flange, resulting in sudden decrease in static pressure in the exit of the diffuser. This will increase the velocity through entrance of the wind turbine and is responsible for power augmentation in the wind turbine. Contour plots show an increase in velocity up to optimum flange angle of 15°, and then it decreases gradually afterwards. The results obtained in the present analysis are in good agreement with the previous published experimental work.

There is an urgent need to explore the substitute for conventional fossil fuel in light of environmental sustainability. Attempts were made to improve engine efficiency and to reduce greenhouse gasses by certain modification in the use of biofuel. In the present work, experiments have been performed on a single cylinder, four-strokes, direct injection, diesel engine with cottonseed biofuel and its blends. In order to ensure complete combustion of the fuel, cylinder head and piston crown have been coated with yttria partially stabilized zirconia (YPSZ) for a thickness of 0.2 mm. The plasma spray technique has been used for coating engine components. Combustion properties of the cottonseed oil have been improved with the transesterification process. The experimental results showed significant improvement in performance and reduction in emission characteristics of a coated engine. The biodiesel blend B10 and B25 showed good results compared to diesel in an uncoated and coated engine, respectively.

In the present work, experiments were carried out on four-stroke, single cylinder, water cooled, constant speed, variable compression ratio (VCR) diesel engine. Experiments are done with the engine being fuelled with DI diesel fuel followed by fuel blends of RME20 (20% rapeseed methyl ester and 80% diesel), RME40 (40% rapeseed methyl ester and 60% diesel) and RME100 (pure rapeseed methyl ester) on volume basis. Performance and emission characteristics of diesel and rapeseed methyl ester (RME) with diesel blends are examined. The engine speed is maintained constant at 1500 rpm at different loads and at compression ratios of 16:1, 17:1 and 18:1. The performance parameters like brake thermal efficiency (BTE), brake-specific fuel consumption (BSFC) and exhaust gas temperatures are measured, and the results are recorded. The emission parameters like carbon monoxide (CO), carbon dioxide (CO2), unburnt hydrocarbons (UHC), nitrogen oxides (NOx) and smoke are measured. The correctness of experimental results is analysed with artificial neural network (ANN). Artificial neural network is a tool to efficiently predict the combustion, performance and emission characteristics by using measured data. Artificial neural network toolbox in MATLAB software is used for simulation of engine parameters. The coefficient of determination R2 values is in the range of 0.942–0.990.

A mathematical model has been developed to study the synchronized effects of particle drag and slip parameter on velocity and rate of flow in an annular cross-sectional region bounded by two eccentric cylinders. In physiological flows, this phenomenon can be seen in blood flow in an eccentric catheterized artery in which the inner cylinder (Catheter) wall is impermeable and the outer cylinder (Artery) wall is permeable. Blood is a combination of plasma in fluid stage and suspended cells as well as proteins in particulate stage. Arterial wall gets damaged due to aging, and lipid molecules get deposited between damaged tissue cells. Blood flow increases toward the damaged tissues in the artery. In this investigation, blood is shown as a two-phase fluid as one is a fluid stage and the other is particulate stage. By using conformal mapping, the eccentric annulus will be transformed as concentric annulus to predict the velocity of the fluid phase and the rate of flow. Modeled governing equations will be solved analytically for the velocity and rate of flow. The examination is taken by changing the eccentricity parameter, slip parameter, and drag parameter. The increase of slip parameter indicates loss of fluid, and then, the velocity and rate of flow will be reduced. As particulate drag parameter increases, then the velocity and rate flow will be reduced. Eccentricity facilitates transfer of more fluid; then, the velocity and rate of flow also increases.

Blade thickness and blade height are the most influencing parameters on the performance of pump. The fluid flow passage can be optimised by the blade thickness. Energy consumption by pump is reduced by employing appropriate blade height. The objective of the present study is to optimise the blade geometry, viz. thickness and height. The duty parameters considered in the present study are flow rate (Q) 5000 LPH, Head (H) 28–26 m and speed 6000 rpm. Numerical simulations are carried out to study the pump performance. Three-dimensional, steady-state flow equations are solved in ANSYS CFX along with Reynolds-averaged Naiver–Stokes (RANS) equations with standard shear stress transport (SST) turbulence models. The results showed that energy consumption decreases with blade height.

Mixing and combustion efficiencies are two important parameters to visualize the performance of scramjet. The rate of combustion strongly depends on the rate of mixing of fuel and air; hence, the mixing efficiency of fuel and supersonic airstream is the major parameter to optimize the performance of scramjet combustor. In this research paper, the numerical investigation has been carried out to enhance the mixing efficiency of fuel and supersonic air by using passive techniques. The passive techniques are implemented to DLR scramjet by creating the wall attached fuel injectors at various locations and developed different computational geometries. Computational fluid dynamics tool ANSYS Fluent 15.0 has been used to solve the fluid flow governing equations and reaction mechanism of fuel and air along with finite rate/eddy dissipation reaction model. Shear stress transport k-ω turbulence model is used for turbulence modeling. Validation of results has been performed with the DLR experimental results available in the open literature and identified a good matching of numerical and experimental results. From the analysis and comparison of numerical results for different passive techniques, it has been noticed that more recirculation regions, oblique and expansion shock waves are developed with the wall attached fuel injectors along with strut injector. These are very much helpful to penetrate into fuel stream and increasing the fuel carrying capacity, which can increase the mixing of fuel and supersonic air.

The present numerical simulation was performed with the objective to study the fluid flow and heat transfer characteristics of a corrugated wavy channel and compare its thermal performance with that of a straight channel with the same geometrical parameters. Both the considered channel had rectangular cross section, and one of them had triangular corrugations with a corrugation angle of 21.8°. The flow was assumed to be laminar through the channel with Reynolds number (Re) varying from 500 to 1500, and the analysis was performed under steady state and constant heat flux (10 kW/m2) conditions. For quantitatively analyzing the heat transfer enhancement rate, Nusselt number (Nu) was estimated along the top front corrugated line (TFCL) and it was found that Nu values increased with increasing Re. Also, the triangular corrugated channel was found to outperform the straight rectangular channel with regard to its comparatively high Nu values which increased by 47.8%. The increased Nu values upon incorporation of corrugations were thought to be due to the formation of recirculation zones and high-intensity swirl flow near the vicinity of corrugations. The only analyzed disadvantage of such a channel was found to be its rise in pressure loss value with increasing Re.

Biofuels like ethanol, biodiesel and butanol have attracted attention of people worldwide and found to be the successful alternates of petroleum products. Slight reduction in emissions is observed when biofuels are used in place of Diesel [1]. In the present work, the emission characteristics of CI engine with diesel–butanol blends using intake pressure boost are shown. For improving the performance of any engine, either we have to go with fuel properties or we have to use advanced technologies. In this study, we are doing both by using diesel–butanol blends and by using an intake pressure boost by varying its intake pressure to cylinder. The investigation results showed that the emission and performance parameters of the engine with intake pressure boost were improved in comparison with naturally aspirated engine.

Thermal protection of scramjet engine combustor wall for long-duration operation is one of the major challenges. Regenerative cooling of the combustor walls using hydrocarbon fuel as a coolant is one of the best solutions to withstand high heat transfer rates for the long duration application. In such a case, before embarking on materials development and fabrication, it would be most beneficial to have a procedure that simultaneously selects the preferred material and design. Thermal design methodology of regenerative cooling system for hydrocarbon fueled air-breathing engine walls is presented in this paper. The main ingredient is three-dimensional heat transfer analysis coupled with fluid flow based on FEM that can be used for the thermal management study of regenerative cooled panel configurations and selection of materials including Thermal Barrier Coatings (TBCs). The procedure is applied for the thermal design of fuel-cooled scramjet combustor walls exploiting physical heat sink of hydrocarbon fuel. High-temperature materials, viz., Cb-752, C-103, and C-SiC are considered as the candidate materials along with TBC. Results of the analysis carried out for several combinations of material of construction, TBC with suitable bond coat material, wall thickness, and channel location are presented. It is inferred that TBC along with regenerative cooling is playing a major role in reducing the engine wall temperature thereby maintaining the fuel temperature inside the channels within desirable limit. The Cb-752 material coated with Y2O3 TBC remains viable solution for thermal management of scramjet engine walls for the long-duration application.

Shock wave boundary layer interactions in the flows over high speed vehicles are considered to be challenging and essential to analyze. Importance of analyzing these for the design of thermal protection system brought it under the active research in the field of compressible flows. In this scenario, an attempt has been made to study the laminar shock wave boundary layer interactions in hypersonic flows over double cone geometry numerically to obtain thermal load variations as well as surface pressure variations on the surface of the vehicle. An open-source CFD tool OpenFOAM based on the finite volume method is used for the current study. The numerical solution captures all important features of the flow accurately and the obtained results are following the corresponding trend and matching with experimental results. Since slope limiters are capable of causing significant changes in the solution, two different slope limiters—vanLeer and superbee—have been used to check the influence on the solution. It is found that the superbee limiter is more accurate than vanLeer but inducing spurious spatial oscillations.

Hypersonic carrier vehicle airframe experiences high rate of heat transfer caused by aerodynamic heating due to very high-speed flow during flight. A wire tunnel over the carrier vehicle is used to accommodate the communication and electric cables routed along the external surface of rocket motor casing from electronics packages section to rear part of the carrier vehicle. The wire tunnel leading edge forms an external protuberance. The protuberances are subjected to severe heating during the flight, especially at hypersonic speed. Thermal design of the protuberance structure is imperative to ensure safe operation in the severe thermal environment experienced during flight. This paper describes the thermal design of wire tunnel protuberance. Further, the design of wire tunnel assembly is ascertained by thermal test conducted in the infrared heating facility for aerodynamic heating condition corresponding to the flight trajectory.

The present work aims to present the suitability of pure jatropha biodiesel and it blends as diesel engine fuel. The jatropha biodiesel is prepared by the alkaline-catalysed transesterification process. The biodiesel blends are prepared in the proportions of 20, 40, 60 and 80%. Experiments are conducted on a single-cylinder water-cooled diesel engine at various loads. The performance characteristics are analysed in terms of brake thermal efficiency and brake specific fuel consumption. The brake thermal efficiency of the engine decreases with increasing proportion of jatropha biodiesel. The exhaust emissions such as HC and CO are reduced as compared with neat diesel. However, NOx emissions are increased. Overall the 20% jatropha biodiesel blend is suitable alternate fuel for a diesel engine without any modifications.

In this study, the fluid–structure interaction of blood flow through a flexible tube with 90° has been analyzed. The numerical investigations are done using open-source CFD toolkit OpenFOAM. The variation of the time rate of change of volume and pressure wave in the case of a flexible tube with the 90-degree bend is evaluated and compared with that of flexible straight tube. It is found that the flexible tube with the 90-degree bend has undergone more rate of change of volume compared to that of flexible straight tube.

Composite pipes are extensively used in various automobile and aeronautical applications due to their high strength to weight ratio. The aim of this work is to numerically analyze the damage and failure of short carbon fiber composite pipe with short carbon fiber as reinforcement and epoxy as matrix. A finite element model was developed in ANSYS workbench 19. A method is discussed to generate short fibers randomly oriented in the volume of composite pipe and the material properties were given to the fibers and matrix. A method is developed to model a composite pipe having anisotropic properties which means young’s modulus change with direction along the object as the fiber is of carbon and matrix is epoxy. Hydrostatic pressure was applied on inner and outer surface of the composite pipe. The results were compared with the laminated composite pipe and neat epoxy composite pipe. It was observed that under the same loading conditions the strength of the short carbon fiber composite was comparable with the laminated composite pipe. Short carbon fiber composite pipe which is less costly having good strength can be a good replacement for the costly filament winding pipe.

In the present work, an effort is made to investigate the Dynamic performance analysis of a four-ton Automobile chassis due to road undulations. The effects of forcing frequencies due to engine as well as road condition are significant at high speeds of an engine. Numerical analysis is employed on the original dimensions of the chassis of heavy truck made of structural steel. The analysis is extended to fiber-reinforced composites and a combination of structural steel and composite. A new mathematical model is proposed as a 2D beam element with consistent mass matrix solved for mode shapes using determinant-based method. However, the natural frequencies for composites are obtained from the effective stiffness value derived from lamination theory. The study involves the change in dimensions, the addition of cross members to the chassis at maximum deflection, and change of materials of the chassis. Further, under the conditions of base excitation, applying engine harmonic load on the cross members, rolling and pitching conditions, the dynamic response of the chassis are determined. The results show that fiber-reinforced composites have low natural frequencies with 80% weight reduction in comparison with structural steel resulting in increase in payload, life of wheels, and other mounting elements on chassis.

The connection behaviour of square hollow section as column welded with I-section as beam (SHCWIB) is commonly used in the construction of modern steel buildings. The behaviour of such connections under elevated temperature or fire load is limited. In this paper, the experimental studies on the behaviour of SHCWIB connection, subjected to an elevated temperature (of 600 °C) and mechanical load, are presented. The beam-to-column connection is initially exposed to the elevated temperature and then cooled to the room temperature. Pre-thermally damaged connection is subjected to an increasing monotonic load while the column member is subjected to a constant axial compression. It is observed that the connection failed at lower loads due to the combination of P-delta effect and pre-thermal damage.

The present work studies the influence of the higher-order non-uniform rational B-spline (NURBS)-based discretizations on the oscillations of contact reaction forces for the large deformation and large relative tangential sliding contact problem. The segment-to-segment-based Gauss-point-to-surface isogeometric contact formulation is used to express the contact contribution to the discretized weak form. The penalty method is adopted for the regularization of the impenetrability contact constraint. The frictionless sliding contact problem involving two deformable bodies is considered for examining the variation in the distribution of contact reaction force on varying the interpolation order of the NURBS-discretized geometry. The solution with a very fine mesh is used as a reference. The study shows that the accuracy of the contact solution improves on increasing the interpolation order of the NURBS. Compared to a very fine mesh, higher-order NURBS with a coarser mesh can achieve the nearly same result at a much lower number of degrees of freedom.

Traditional methods for solving constrained optimization problems are not robust enough to get the solution in reasonable computational time. They have drawback of getting stuck in local optima. To overcome these problems meta-heuristic techniques are now widely used. This paper introduces simple optimization algorithm (SOPT), a meta-heuristic technique for solving constrained optimization problems. To handle the constraints, a constraint fitness priority-based ranking method is included in the algorithm. SOPT algorithm for constraint optimization is coded in MATLAB and applied to design a uniform column for minimum design cost. Result obtained is compared with the result obtained by another important meta-heuristic algorithm called cuckoo search (CS) algorithm.

Online estimation of most severe unbalance fault in a high-speed rotating machinery system such as pumps, gas turbines, etc. is very essential for their smooth functioning. In the present paper, an estimation methodology has been developed to obtain the unbalance parameters such as magnitude and phase of unbalance as well as AMB dynamic parameters such as force–displacement stiffness and force-current stiffness constants in a rigid rotor system mounted on active magnetic bearings. These dynamic constants of AMB play a vital role in the rotordynamic vibrational analysis, which includes improving the stability of the system and control performances. A mathematical model consisting of a rigid rotor with a disc at the middle position supported on two active magnetic bearings are developed for this estimation purpose. Equations of motion of the rotor system are derived and simulated numerically to generate displacement and current responses of the rotor system in the time domain. A fast Fourier Transform technique is utilized to convert the time domain response into frequency domain signal, which has been further used in the developing methodology to estimate the unbalance fault parameters as well as AMB’s constants. The results estimated were found showing high stability and good accuracy.

Geckos can generate strong attachment forces and at the same time detach swiftly from any surface by employing the hierarchical fibrillar structures on their toe pads. In this paper, a coupled adhesion-friction model in the framework of nonlinear finite element analysis is used to analyse the peeling behaviour of gecko spatulae. It has been found that the material stiffness, adhesion strength, size of the spatula, and adhesion range greatly influence the spatula stresses, pull-off forces, and deformation behaviour.

This study is described on the optimization of tribological characteristics of Al–coconut shell ash (CSA) reinforced composite prepared with stir casting route. In this study, three operating variables (i.e. load, sliding speed, and % of CSA) and two response [i.e. wear rates (WR in mm3/m)] and coefficient of friction (CF) are considered. The list of experiments was intended using L27 orthogonal array (full factorial design). The influence of each parameter on the response is established using response tables and response graphs. Based on experimental data, the model equations for each response were developed with multiple linear regressions. The models give the factor effects of individual parameters. Interaction effects provide additional information to understand the detailed behaviour of parameters. It revealed that load is the most influencing effect on wear behavioural responses.

Since the last two decades, pre-strain remained proficient techniques to enhance actuation performance of dielectric elastomer actuators (DEAs). However, the influences of pre-strain on properties of elastomer are widely explored. But their co-relation with (macro)molecular structures is lacking in the literature, which give a path to control the properties of dielectric elastomer. Here, the attributions to pre-strain imposed change in electromechanical properties of VHB 4910 elastomer are discussed well and the modification in molecular structure is also shown. A significant change in infrared spectra is observed, and the emergence of new bonds is co-related well with the physical phenomenon of strain hardening. The result may be helpful to transform the structural integrity and to improve material properties for highly efficient electromechanical actuation.

Dielectric elastomers (DEs)-based electromechanical cylindrical actuators are applicable in the field of biomimetic, robotics, microfluidic pumps and similar instrumental devices. However, to achieve efficient actuation performance, significant attention is requisite towards influences of pre-strain on electromechanical properties. This study shows the effect of pre-strain-induced variation in dielectric permittivity to improve the performance of the existing model for a cylindrical actuator. Modified electromechanical model is proposed for a thin-walled actuator configuration. The hypothesis of linear elasticity for small deformation is used to derive the novel model for voltage-induced axial strain. The analytical results shows improved axial actuation strain with relatively less errors and the values are found in good agreement with experimental results. This may encourage future researchers to identify crucial parameters on the way to design and optimization of soft actuators.

One of the major concerns for the structural failure of an airplane wing is due to the initiation of crack and its propagation. The literature survey on aircraft failure indicates that the main source of failure is due to fatigue cracks, which propagate from the wing root region. The modal analyses is one of the important tool used to determine the dynamics behaviour of airplane wing structure including natural frequencies and modes shapes. In the present study, an attempt has been made to perform the modal analyses of aircraft wing structure without cracked airplane wing structure and with cracked airplane wing structure (NACA2415). The results of modal analyses for uncracked wing structure are compared with the results reported in the literature. The main objective of the present study to do the comparative study of modal analyses for with or without crack in aircraft wing and analyses the results which show that natural frequency is affected in presence of crack. The effect of the crack length, depth of the crack and location of the crack on natural frequency is also investigated.

The maintenance of various automotive systems has been increased due to improper road conditions in developing countries which results in shorter lifespan of the automotive components like wheel bearing and also discomfort ride of a vehicle which further increases the maintenance and running cost. The problem with friction and wear of various automotive systems like bearing with their noisy operation is becoming more prominent. Therefore, there is need of lubricating greases which decreases friction, wear and noisy operation while maintaining the vehicle. Grease is an important element in the automotive wheel bearing lubrication. Considering emerging need for high load-carrying capacity and viscosity, a new kind of bearing lubricants is required. Nano-grease has the potential to fulfil the emerging needs of lubrication. Now days, there is scope and also challenge to develop new grease for specific application. In this paper, samples of nano-grease are synthesized and characterized for thermal, tribological and rheological properties. The characterization results of nano-grease are compared with conventional greases and suitable nano-grease has been suggested for automotive wheel bearing application.

The evolution nonlinear partial differential equations give an insight into the physical, mechanical, thermal, electrical and electro-mechanical behaviour of a nonlinear system. The study of these evolution equations and their solutions, especially in plasma transport through magnetic field lines, is essential to understand important principles applicable for transportation of plasma, such as magnetized plasma diffusion. It also has application to the sources of plasma which work at low temperature and pressure. One such PDE is the modified Kdv–Zakharov–Kuznetsov equation. These equations have solutions that are best described by solitons, kinks and periodic wave-type travelling wave solutions. The Hamiltonian- and the rational trigonometric method-based travelling wave solutions of these evolution equations are obtained. These solutions are also comparable with semi-analytical approaches such as tanh method, exp-function method, Jacobi elliptic function method, Jacobi theta function method, and numerical approaches such as Pertrov–Galerkien method and radial basis function method. The solutions obtained here are compared with the recent work by extended mapping method and Jacobi elliptic method and $$\frac{{G^{\prime}}}{G}$$ method.

Rotary unbalance is the main cause of vibrations in high-speed rotating machines. Thus, a test rig is required for training personnel relating to this area. The existing balancing test rigs are costly. Availability of low-cost sensors and development boards like Arduino Uno helps in fabricating the test rigs at low cost. The rig contains four masses mounted on a disc such that radial position can be varied. Vibrations are measured when the disc is rotating. For measuring vibrations, pre-calibrated ADXL335 accelerometer, which is available off the shelf, is used. This is interfaced to PC using Arduino. The measured unbalance is found to be in good agreement with that of theoretically calculated value. This test rig helps in bringing an insight into students as to how unbalance can be estimated and corrected as well as use of various commercially available vibration measurement sensors.

The present development on the automotive engines on reducing size and increasing greater fuel efficiency, and less emissions took the researchers to several challenges in turbocharger rotor system. However, the challenge towards the evolution of high-efficiency bearing systems with reliability is still over the top. The paper shows the system with dynamic analysis of nonlinear turbocharger rotor system to interpret the unstable positions during running condition. The proposed model of turbocharger in this study is examined as a uniform shaft in nature with varying lengths between two bearings which actually held between compressor end and the turbine disc. The two discs are having force unbalance and the compressor impeller exists with the seal forces. The rotor considered here is supported by bearings with the nonlinear time-varying forces as reactions at the supports. The approach in this paper is allowed to solve the transient conditions, suchlike nonlinear effects due to seal forces, time histories, and Campbell diagram. The computational models are solved with analytical equations using finite element modelling (FEM) and the obtained results are verified with ANSYS® simulations. The impacts of different operating conditions at two different speeds are studied by phase-plane diagrams to understand the stability of the system.

The dynamic responses of a beam structure acted upon by a moving mass or moving load have been of great importance in the design and study of bridges, railway tracks, etc. It also plays a vital role for studying many applications in the field of transportation, overhead cranes, cableways, roadways, pipelines, tunnels, bridges, guideways, etc. All the above-mentioned structures are designed to support moving loads. The structures while supporting the moving loads face the inertial effect of the moving mass which cannot be ignored comparing with the gravitational effect of the moving load. The equation of motion of an Euler–Bernoulli beam acted upon by a concentrated mass moving at a uniform speed is formulated in matrix form. The solutions of the above problems for cantilever beams are evaluated by using dynamic Green’s function approach. The present work focuses on the effect of the mass of the moving load and its speed on the response of a cantilever-type beam. The cantilever beam is divided into twenty divisions, and the deflection of beam at the free end is measured, while the mass moves with uniform velocity over the beam through different stations. The deflection results so obtained are plotted in the form of graphs for different velocities of mass.

The present work is concerned with fatigue life prediction of active components of deep drawing dies. Finite element analysis is performed, and S-N approach is used to evaluate the number of cycles of deep drawing die. Based on the available evaluated data (from FE analysis) and mathematical formulae, the ANN program is developed in the MATLAB, which is used to predict the fatigue life of active components of deep drawing dies. The developed ANN program achieved satisfactory results and verified based on a demonstration of an industrial component.

In the past few years, natural fibers became one of the most widely used materials in place of synthetic fibers to develop composites as it attains some inherent characteristics like renewable resource and biodegradability. Pineapple leaf fiber (PALF) is one of the natural fibers which can be used as reinforcement to develop composites. The objective of the present work is to carry out the analytical study of mechanical and thermal properties of fiber-reinforced polymer composites. PALF in unidirectional form is used as reinforcement with varying fiber volume fraction $$(\upsilon_{\text{f}} )$$ ranging from 10 to 70% and epoxy as the matrix material to carry out the work. Representative elementary volume (REV)-based micromechanical analysis is used to determine elastic and thermal properties of composites. The results obtained from this analysis are compared with that of the existing analytical methods. The results show good agreement between the results of finite element analysis (FEA) and analytical methods.

Considerable research has been devoted to the design, optimization, and development of bio-stents in the last few decades. This paper reviews many existing stents and suggests an optimized structure of stent that satisfies all constraint functions including stress generation in the artery since the arteries also have some limitation in enduring stresses both in longitudinal and circumferential directions. The best stent structure among the seven optimized stents reported in the literature, based on the combined behavior of the artery and the stent-like foreshortening and elastic radial recoil, is suggested. A unit cell of the stent is considered along with a cylindrical artery to reduce the computational time. The finite element method is used to determine the mechanical integrity of the stents at various load conditions during and after its deployment. The stent is also analyzed for two different materials, stainless steel and Nitinol, that are used for stent manufacturing and the results are reported.

Electroactive polymers (EAPs) have been widely employed as smart material for actuation and sensing in recent years. Dielectric elastomers (DEs) are a type of smart material which belongs to the class of EAPs. Their applications include soft sensing and actuation which require high sensitivity, flexibility and stretchability. They can be actuated under electric field responding to an electrostatic force. Compared with other electrical actuation technologies, the advantages of dielectric elastomer actuators include lightweight, good compliancy, high energy density, large actuation strain, quiet operation and low cost. The current research focuses on the electro-mechanical actuating behaviour of DEs embedded with composite using finite element approach. Analyses are carried out with three different support conditions of the composite, on which the elastomer is mounted, and with varying thickness and positions of elastomer on the composite at various voltage levels. Results indicate that strain in the composites increases with a decrease in the thickness of the elastomer.

With the growing need of fast production to meet the requirement of the industry, mass production machines like hydraulic, tracer control machine tool, special purpose automatic and semi-automatic machines were introduced with the advancement of technology. The use of these machines has considerably reduced production costs by way of reduced machining time and labor cost. This has excited the research to develop another special purpose machine—CNC 2D rod bending machine. Presently, available CNC 2D bending machine is very costly. The present research work focusses on developing a low-cost CNC 2D bending machine using pneumatic and single-axis CNC system, capable of bending metal rod ranging from 3 to 6 mm diameter, in the length range from 1 foot to 8 feet, of rod material mainly stainless steel and mild steel with maintaining cladding material and appearance. The methodology is applied to design the feeding and bending mechanism to overcome the above-stated problems. The mechanisms are not only designed but also manufactured. Its cost reduced by 35–45% compared to available machines in the market. It sets the classical example of design for manufacturing.

The paper discusses the evolution of a robotic mechanism which can closely follow the perimeter walls of a coal bunker. A mechanism, which slides on a track along the perimeter and guides the scraper, is constructed. The robot is designed keeping in mind its rigidity and achieves its functionality. The most desired parameter of this robot is the proximity to the walls when the scraper moves to all altitude levels of the bunker. The mechanism discussed permits the scraper to be guided along the walls of a rectangular frustum. Design and selection of parts were done by conventional methods. Workspace analysis of the resultant mechanism was done in MATLAB to ascertain the reach of the scraper. The kinematic development of the mechanism is discussed in brief. The design criticality of structural members was analyzed numerically.

The impulse excitation technique (IET) is one of the most reliable and non-destructive techniques to measure dynamic elastic properties of materials. It is also possible to measure the damping factor and the resonant frequency of materials using this technique. In the current study, IET is used to measure Young’s modulus, natural or resonant frequency (fr) and damping factor (Q−1) of friction stir processed pure metals with an intention to assess their vibration damping ability. Commercial pure aluminium (Al), copper (Cu) and magnesium (Mg) metals were subjected to single-pass friction stir processing employing 600 RPM of tool rotational speed and 60 mm/min of travel speed. The specimens for IET analysis and for microstructural observations were extracted from the stir zone of friction stir processed plates. The microstructure in the stir zone is severely refined by the friction stirring particularly the grain size of magnesium refined to 25.6 µm from its initial size of 780 µm. The measured Young’s modulus and natural frequency for the processed Al and Cu samples were interestingly lower than their as-received counterparts. But the damping ability of these metals significantly improved after processing. However, for magnesium, the observed trends in the properties before and after processing were quite opposite to the other two metals. The crystal defects created during the friction stirring could be a reason for the observed trends.

The study proposes a new rectangular finite element of 16° of freedom based on hermitic cubic polynomials, for investigating the strength of a thin rectangular FG plate compared to conventional materials like pure ceramic or pure metals on the aspects of static and dynamic performance. A power law variation in material properties is assumed across the plate thickness. Mori–Tanaka homogenization scheme is employed for micromodeling of the FGM. A thin plate of particulate silicon carbide and aluminum matrix functionally graded composite is designed which is analyzed based on classical laminate plate theory and tested to clamped and cantilevered boundary conditions. The results are generated using MATLAB programming and validated using ANSYS commercial FEA package.

The present study uses the molecular dynamics approach to study the various defects available in graphene sheet and also to record its effect on the strength and stiffness of graphene. The graphene sheet is uniaxially deformed in its armchair and zigzag direction. In order to examine the fracture behaviour of defective graphene, molecular dynamics (MD) simulations based on AIREBO interatomic potential field and Nose-Hoover thermostat and barostat techniques are implemented. The present study shows that with the introduction of the defects, the fracture/yield strength of graphene reduces up to some extent in both of its direction. However, the presence of crack reduces the strength of graphene significantly more. Further, the study also concludes that the graphene withholds much higher stress when loaded in its zigzag direction in comparison with loading it in armchair direction.

New advanced non-destructive evaluation (NDE) methods such as single-sided nuclear magnetic resonance (NMR) and Acousto-ultrasonic methods are being developed for their advantages and high resolution for defect detection in composite structures. Glass fiber-reinforced plastics (GFRP) composites are being used for many industrial applications. Rubber lining in layers is done to the composite inner surface to meet the industrial requirements. The interface of GFRP composite and rubber lining is very critical. Any de-bond (separation of adhesively bonded liner from composite surface) at the interface and delamination between rubber layers may lead to failure of composite structure due to corrosive gases and liquids. NDE of such structures is challenging due to their high attenuation of ultrasound and poor radiography defect signatures. The present study reports application of proton single-sided NMR method to evaluate the de-bonds of rubber liner with composite and delamination between rubber layers. Results are compared with Acousto-ultrasonic method, which uses low-frequency mechanical waves for inspection. Results indicate application of both these techniques for evaluation of bonded interfaces. Advantages of both the techniques over conventional techniques have been discussed.

In the present study, the dynamic response of the cantilever was studied by exciting it using a vibration exciter. The aluminium cantilever beam was excited with random and sine vibration conditions, and the response of the beam was obtained using accelerometers. The natural frequency and the free end oscillations were studied. The natural frequency varied with material due to their stiffness. The displacements at free end were higher for shock loads whereas they were lower for random vibrations. The trends of the vibration response with acceleration remain same for both types of vibration but the variation between them was visible only at higher accelerations.

This work presents an active vibration control scheme in high-speed turbocharger rotor system. The working speed of these rotors is very high so a small vibration may damage the system, so there is a requirement to control such unwanted vibrations. Most of the cases these rotors are supported on the floating ring bearings. Initially, the rotor model is developed with finite element method to get the dynamic response of the system due to unbalance and gravity forces. The nonlinear hydrodynamic bearing forces are computed and the equations of motion of multi-degree of freedom turbocharger model are solved with time integration scheme. After obtaining the parametric effects of the bearing on overall system response an electromagnetic actuator system is adopted to control the vibration amplitudes in the system. The methodology is found to be reliable and reduces the vibration amplitudes considerably.

Underwater weapons in defense application are used to hit against enemy ships and submarines. These are designed to operate under extreme depths which require minimization of structural weight for increasing the performance, speed and operating range. This paper deals with the design and analysis of assembled system made of aluminum alloy and CFRP material. It mainly consists of different subsystems. These subsystems are used to accommodate different varieties of electronics and other systems required for underwater applications. These subsystems generate the heat fluxes which are transferred to both ends of the system. In addition, this underwater system also subjected to external hydrostatic pressure during functioning. Hydrostatic and thermal loads can cause system failure due to shell expansion and O-ring failure and can cause water leakage into the vehicle compartments. This paper mainly concerns about the avoidance of system failures and increase the efficiency of underwater vehicle. Coupled analysis (thermal and hydrostatic) carried out for existing design using ANSYS finite element analysis software. With this analysis stresses, deformations and strains of vehicle are found out for existing design. Buckling analysis also carried out for subsystem shells for finding the buckling pressure. This analysis proves the stresses and buckling pressures are within the limits. This analysis is used to identify the weak zone and most affected area of the vehicle which helps for the modifications and remedies for underwater vehicle.

As the use of eco-friendly, natural products is currently increasing, reinforced composites from Basalt have recently been developed. These amorphous mineral fibres are a suitable alternative to low-cost carbon fibre and strong glass fibres. The basalt and carbon fibres of uni-directional and bi-directional with lay-up sequence of (0/90/±45/±45/0/90/±45/±45/90/0) that are used to strengthen composites by the vacuum bagging technique. A mechanical characterization is required in order to use reinforced composites for structural applications. Different tests such as tensile and flexural tests are carried out in both the experimental and analytical method to show mechanical characteristics. Finally, the obtained results propose to emphasize the behaviour of reinforced composite fibre. The enhanced properties put forward possible applications of such composite materials in various fields.

Steering mechanism is very essential for any road vehicle. The commonly used mechanism for steering is the Ackermann mechanism. The perfect steering demands that the extensions of the axes of the two front wheels intersect at a point on the extension of the common rear wheel axis. The Ackermann mechanism does not give perfect steering always. In this paper, an attempt is made to arrive at optimum dimensions of the links of the mechanism which make the error in steering minimum.

In the present work, an attempt has been made to generate protruded and dimpled textures on the rake surface of high-speed steel (HSS) cutting tool by an ink-jet print followed by chemical etching (IPCE) process. The orthogonal turning of Aluminum 6063 alloy was conducted by using textured and non-textured tools. The results revealed that cutting forces and friction coefficient are reduced with textured cutting tools. Moreover, the protruded textured tool exhibits better performance than the dimple-textured tool.

Recently, there is a growing interest in molybdenum disulphide (MoS2) to use as a solid lubricant to enhance the tribological properties. In the present work, composite MoS2/TiO2 coatings were prepared and bonded on pre-treated steel substrate. The manganese phosphating process has been used as a pre-treatment which helps to improve the bond strength. The coating has been bonded onto the phosphated substrate using sodium silicate as a binder. A comparative study of these composite coatings was done at different temperature, load and speed conditions using pin-on-disc tribometer. The results depict that the tribological performance such as friction coefficient and specific wear rate has been improved by coating material as compared to uncoated material.

Optimization is carried out to achieve the best out of given resources while satisfying constraints on performance, state variables, and resources thus avoiding the excessive use of resources and decrease the cost associated. Structural systems need to be designed for a minimum of weight, compliance, displacement, frequency, etc., to save cost and get optimal performance. For this, structural optimization is carried out. Topology optimization is one type of structural optimization in which topology of the structure is changed. Generally, topology optimization is performed using methods like solid isotropic material with penalization (SIMP), level set-based methods, phase field method, evolutionary structural optimization (ESO), and bidirectional evolutionary structural optimization (BESO). In the present work, a modified evolutionary algorithm is proposed for structural optimization with consideration to strain energy distribution. Addition of material is performed on a partially void space instead of material removal. As the final optimum structure bears only a fraction of initial structure, the method of structure growth using addition approach is better for computational efficiency. This method initially takes a void input design domain but to make numerical computation easy, negligible density is assumed. The objective is to achieve critical strain energy per unit volume which is less than the modulus of resilience according to the maximum strain energy criterion. According to the maximum strain energy theory, a safe structure should have strain energy per unit volume less than the modulus of resilience. Hence, the objective is to find a structure satisfying the above criterion with minimum weight. The main focus of the work is to find optimum topology. Effect of multiple loads, rate of material addition, and effect of the magnitude of loads are also considered for structural optimization. The results are close to the results reported in the literature.

Inverse kinematics and trajectory planning are important for rehabilitation robotics and exoskeleton design. In this paper, a three-link three-dimensional kinematic model of a human leg is defined and its kinematic analysis is performed with the focus of optimizing its manipulability. The biomechanics data is used to obtain the range of motion limit and comfort zone of every joint. The forward kinematics of the leg is used to obtain the workspace of the human leg. Using inverse kinematics, the final joint angles for the desired three-dimensional position are obtained. The inverse kinematics of human leg model is formulated as a constrained optimization problem to get the optimum joint angles under different task constraints. The fifth-degree polynomial function is used to obtain trajectory from initial to final joint angles. Simulations have been performed on the kinematic model of a human leg for workspace evaluation, inverse kinematic solution, and trajectory planning.

This paper deals with basic concepts, methods and applications of continuum structural topology optimization. The three elements that are geometric modelling, analysis methods and optimization techniques which form the backbone of topology optimization are explained. Various approaches to perform topology optimization are also presented. The concepts are explained in an intuitive way such that new researchers can learn steeply and expand their knowledge by going through vast literature on this exciting research area.

In this paper, a method based on Nelder and Mead’s simplex search method is developed for solving multi-objective optimization problems. Unlike other multi-objective optimization algorithms based on classical methods, this method does not require any a priori knowledge about the problem. Moreover, it does not need any pre-defined weights or additional constraints as it works without scalarizing the multi-objective problem. The algorithm works with a population of points and is capable of generating a multitude of Pareto optimal solutions. Equipped with the constraint handling strategy adopted in this work, the method is found to be competitive with respect to the existing algorithms.

Titanium alloys are used in various applications due to their properties. However, these alloys are difficult to machine. Several techniques have been proposed in the literature to deal with the problem. This paper presents a study on the performance and life cycle analysis of the dry machining, flood lubrication and minimum quantity lubrication (MQL) of titanium alloy, Ti6Al4V. Machining was carried out at different speeds 30, 55 and 80 m/min. Soybean-based fluid was used in both flood lubrication and MQL. Cutting forces, tool wear and surface roughness were measured in all three cases. MQL was found to have better performance with longer tool life by almost two times, cutting forces by about 18% and surface roughness by about 10% compared to dry machining. Flood lubrication results were intermediate between the two. However, flood lubrication had the highest carbon footprint followed by dry machining and MQL.

Titanium (Ti)-based alloy is extensively used in biomedical field due to its unique properties that promotes osseointegration. Present work deals with investigation on the effect of cutting conditions on corrosion resistance in micro-milling of Ti–6Al–7Nb alloy for enhanced biocompatibility. Experiments were carried out based on Taguchi L9 orthogonal array with selected process variables include cutting speed (vc), feed rate (fn) and depth of cut (ap). Micro-slot of size 700 µm for a length of 10 mm was made using high-speed micromachining station under wet condition. Potentiostat setup with three electrodes and simulated body fluid (SBF) at 37 °C was used for corrosion resistance measurement and corresponding Icorr values were obtained from polarisation curve. Icorr values are found to be minimum at higher vc and lower ap conditions. Variation in process parameters influences the surface characteristics to a greater extent, which intern alters the corrosion resisting potential of surface. From the study, it is observed that Ti–6Al–7Nb alloy exhibits higher corrosion resistance under in vitro condition for enhanced biocompatibility for medical application.

The solid rocket motors (SRMs) produced with case-bonded composite solid propellant (CSP) grains are formulated with metallic aluminium (Al) powder as the fuel, ammonium perchlorate (NH4ClO4) as the oxidizer and hydroxyl-terminated polybutadiene (HTPB) as a polymer binder. These CSPs are sensitive to fire hazard by mechanical stimuli such as friction, heat, impact load and static charge which are inevitably present in conventional machining operations. In order to machine this ‘hazardous to machine’ CSP material safely, using custom build cutting tool called ‘turbine cutter’ with minimum cutting power and for maximum material removal rate (MRR), experimental studies are carried out. The main objective of this study is to identify the optimum process input parameters for low cutting power (CP) and high MRR and further to enhance the safety in machining of ‘hazard to machine’ materials. To achieve this objective, the effect of machining parameters on CP and MRR was investigated. Full factorial experiments were carried out on live propellant grain using the turbine cutter on CNC vertical turn mill (VTM). In order to investigate the influence of process parameters in machining CSP material, two-factor interaction (2FI) models are developed, and subsequently, ANOVA is performed to evaluate the significant process parameters. Response surface methodology (RSM) is used to develop the mathematical models and also for multi-response optimization, using commercial software, Design-Expert. The optimum values of machining parameters attained with a desirability value of 0.88 are as follows: cutting velocity (CV) is 125 rpm (196 m/min), table feed rate (TFR) is 24 deg/min (0.418 m/min), and depth of cut is 4 mm for minimum CP and maximum MRR, and their values are 15.75 × 10−2 kW and 1092.11 × 10−6 m3/min, respectively.

The effect of additives like zirconia and titania on the mechanical properties of hydroxyapatite nanocomposites was investigated. Nanocomposites were manufactured through high-energy ball milling (HEBM) at 300 rpm for 1 h was adopted to produce the composite powders. The specimens were fabricated through compacting at 100 bar with a stay time of 150 s and sintered at 1200 °C. X-ray beam diffraction demonstrated that the crystallite and grain size estimate steadily diminished with the expansion in ZrO2 and ZrO2 + TiO2 content till 20wt%, after which there was a sudden rise in crystallite and grain sizes of both the composites. An overwhelming ZrO2 stage was seen in the X-ray beam diffraction (XRD) and smaller scale basic examination (Field Emission Scanning Electron Microscopy—FE-SEM) of the sintered samples. Mechanical properties were observed to be enhanced including 20wt% of ZrO2 and ZrO2 + TiO2 at 1200 °C. There was a drop in the mechanical properties of HAp due to the expansion of 25 wt% of ZrO2 and ZrO2 + TiO2 composites. The drop could be because of the expansion in grain size and prevailing particles of ZrO2.

In this study, Taguchi-based analysis of variance (ANOVA) is adopted for optimization of lower-frequency vibration-assisted turning (LVAT) process parameters such as cutting speed, frequency, amplitude, and feed rate. Machining parameters are analyzed by evaluating maximum cutting force and tensile maximum circumferential residual stress (MCRS) in VAT of Ti6Al4V alloy. Finite element simulations are performed in ABAQUS according to L27 orthogonal array to find the optimum condition for maximum cutting force and MCRS (tensile). Results show that the vibrating parameters, frequency, and amplitude are most significant for maximum cutting force and MCRS (tensile), respectively. The optimum condition is obtained at 30 m/min of cutting speed, 150 μm of amplitude, 600 Hz of frequency, and 0.05 mm/rev of feed rate for cutting force while the optimum condition for MCRS (tensile) is 45 m/min of cutting speed, 50 μm of amplitude, 200 Hz of frequency, and 0.15 mm/rev of feed rate.

The surface temperature history and convective heating rate are the vital design perspectives of the short duration facilities such as IC engines and gas turbines. With this motivation, ‘Thin film gauges’ (TFGs) have been developed by depositing transition metals blended with CNT nanofluid on the surface of highly polished ceramic substrates. For a precise temperature sensor of resistance based, the quality measures on temperature coefficient of resistance (TCR) are recommended. An experimental investigation is performed for finding the performance measures of the sensor. The experimental correlation of TCR is compared with the theoretical interpretation using XRD material characterisation method. An enhancement of performance is identified for CNT-blended TFG, and the performances were validated using analytical model.

The present study involves the transesterification of ineffectual soybean oil using synthesized calcinated (duck eggshell) calcium oxide (CaO) as heterogeneous base catalyst. The catalyst was first prepared by exposing at a muffle furnace for about 180 min 800 °C and then characterized using X-ray diffraction (XRD), Fourier transform infrared spectrometry (FT-IR), scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDX). There is characterization of uncooked, ineffectual and transesterified ineffectual soybean oil using FT-IR spectrometry. The yield was obtained to be 94.55% when transesterified at 3% (wt%) catalyst loading, 10:1 alcohol to oil ratio, a reaction temperature of 70 °C and a reaction time of 60 min. The methyl ester underwent gas chromatography–mass spectrometer (GC-MS) test to check the contents of the yield oil. It was found that the cheap and ready to be discarded ineffectual soybean oil can be effectively used for producing biodiesel.

Cemented tungsten carbide (WC-Co) is preferred cutting tool material, having tungsten carbide (WC) reinforcement embedded in cobalt (Co) matrix. Higher hardness, fracture toughness and wear resistance are the essential characteristics for cutting tool materials and are inherited by cemented tungsten carbide. The controlled distribution of Co composition in the form of gradient makes functionally graded cemented tungsten carbide (FGCC) and results in customized material properties but the only difficulty is Co migration. Additionally, wear resistance of FGCC is further improved by including a solid lubricant in the form of a gradient. The desired gradient is developed by powder metallurgy route using spark plasma sintering (SPS), which eliminates the migration of Co. The present work deals with the development of FGCC with and without solid lubricant and comparisons of their microstructure and hardness. The obtained results confirm the variations of microstructure and hardness in both FGCC samples (with and without solid lubricant). The presence of solid lubricant decreases the hardness, so FGCC without solid lubricant is having a higher hardness.

Mild steel and stainless steels are the two utmost steels used in the automotive industries as well as in various constructional and industrial applications. Welding of these steels with lesser defects and higher strengths is the most important need of the current industries. In this paper, TIG and MIG welding is preformed between two dissimilar steels. Transitional changes happen frequently in physical and microstructural properties; therefore, this study carries out an experimental and microstructural analysis to determine the properties like hardness, impact strength, tensile strength and microstructure of the weld zone.

Thermal management of avionic packages mostly involves bringing down conduction and radiation resistance between the components and the sink. Fans and blowers are not recommended because of the acoustic noise generated and the EMI/EMC disturbance created by them. In this paper, an attempt has been made to find the utility of micro-blower for local cooling of high-power components. The micro-blower is operated by piezoelectric vibrators whose frequency is beyond 20 kHz. These blowers are compact and draw very less power. Moreover, no acoustic noise and EMI/EMC disturbances are encountered. Experimental study has been carried out to find the velocity of air flow with respect to distance from the exit for different input power. To assess the cooling effect of micro-blower on components, components are simulated with patch heater and the case temperature is found for packages with and without blowers, respectively. To find the effect of orientation of components in an electronic package (generally not known), measurements have been carried out for different component orientation. Based on the experiment, the maximum temperature drop and minimum temperature drop were found to be 10 °C and 8.6 °C, respectively. This work facilitates the use of micro-blower for the local cooling of electronic components for avionic applications.

The aim of the present work is to evaluate the mechanical properties of banana and S-glass fiber-reinforced hybrid nanosilica composite. The glass and other synthetic fiber-reinforced polyester composites give high strength when compared with the natural fiber-reinforced composite, but their applications are limited because of the high cost of fabrication. So to overcome the cost of fabrication and to meet the high strength as of synthetic composite, a new hybrid composite is fabricated by using 50% of natural fiber and 50% of synthetic fiber. The new composite is fabricated by reinforcing the stacking layers of woven banana and s-glass fibers with the polyester resin as a matrix and nanosilica as filler material. Different samples were prepared by changing the stacking sequence of fiber placed in the composite and weight percentage of nanosilica powder that is mixed into the resin. The fabrication is done by the hand layup method. The mechanical properties like tensile strength, flexural strength, tensile modulus, and flexural modulus were studied. The morphological study is done through a scanning electron microscope to observe the fibers pullout, stacking of fibers, and the behavior of matrix in the hybrid composite. The change of weight percentage of nanosilica and the stacking sequence of fibers in the composite show the improvement in mechanical properties.

Nano-fillers reinforced with polymer-based composites have found to enhance the tribological properties in polymer composites. Alumina (Al2O3) and molybdenum-di-sulphide (MoS2) were selected as nano-fillers in the present research work. Al2O3 and MoS2 fillers were mixed with the epoxy resin in the concentration of 0.1, 0.2, 0.4 and 0.7% by volume of the epoxy resin. The reinforced epoxy resin was used as a matrix material along with the aircraft grade carbon fabric as the primary reinforcement. Test panels were fabricated using vacuum-assisted resin transfer moulding technique (VARTM), and samples were extracted using water jet cut as per the dimensions given in the ASTM standards of three-body wear (ASTM G-65) and two-body wear (ASTM G-99). Scanning electron microscopic (SEM) studies revealed the even distribution of the MoS2 when disbursed with ultrasonicator than by manual mixing. The three-body and two-body wear tests were carried out at a load of 24 and 48 N. The composite reinforced with 0.4% of MoS2 particulate has shown the decrease in wear rate by 20.45% as compared to that of the Al2O3 particulate-based composites in three-body wear test when the applied load was 48 N, whereas in two-body wear test, the composite reinforced with 0.4% of MoS2 particulate has shown the decrease in wear rate by 16.13% as compared to that of the Al2O3 particulate-based composites. SEM studies of worn-out surfaces revealed that the mode of failure in worn-out samples was due to delaminate at the fibre matrix interface. SEM images also revealed that better bonding between fibre and matrix can be well achieved for the 0.4% concentration of nano-reinforcements as compared to that of the composites with 0.2% concentration of nano-reinforcements.

This paper studies the effect of pistachio shell microfillers on the impact strength of epoxy composites. In the present research endeavor, the potential of pistachio shell as natural filler is examined with the epoxy matrix. Pistachio shell filler-based composites were developed by varying the content of fillers 0, 5, 10, and 15% (by weight). Charpy impact test and moisture absorption test were performed on developed composite specimen. An increase in moisture absorption was observed with the incorporation of filler. The effect of different environmental conditions, i.e. water, petrol, and kerosene, on impact strength was also studied, and test results of specimen were compared with the neat epoxy composite. With incorporation of 10% filler, an increase of 36.56% in impact strength was observed under ambient conditions. Further decrease in impact strength was observed for sample subjected to different environmental conditions. Morphological study of all developed specimen was also done which revealed the brittle nature of fractured surface. The study revealed that the pistachio shell filler has got potential to be successful filler in developing epoxy composites.

The recent industries are more concise about clean, green, and sustainable machining process for better quality and productivity. The conventional cutting fluid is gradually replaced by nanofluid due to heat transfer and the lubricating properties of nanoparticles. The effect of material hardness on grinding performance in terms of surface roughness is determined under different cooling environments such as conventional flooded, MQL, and Nanofluid MQL. The result shows that surface finish of hard material is obtained better at 0.30 vol.% concentration of nanofluid compared to conventional flooded, MQL and 0.15 vol.% concentrations of Nanofluid MQL process. In present work, the modeling and optimization of process parameters for EN 31 soft material are carried out using Jaya algorithm to improve the process performance. The process parameters such as table speed, depth of cut, dressing depth, coolant flow rate, and nanofluid concentration are considered the input parameters and surface roughness as the response parameter for model development. The optimal values obtained by Jaya algorithm for soft steel material in Nanofluid MQL process are table speed (7000 mm/min), depth of cut (20 µm), dressing depth (10 µm), coolant flow rate (750 ml/hr), and nanofluid concentration (0.22 vol.%). The result shows that Nanofluid MQL process significantly reduced the surface roughness by 14% over the conventional technique. The confirmation experiments are conducted to validate the regression model by comparing the experimental results with predicted values obtained from Jaya algorithm at optimal setting.

The tribological behavior of the different structural steels with carbon concentration ranging from 0.002 to 0.7% was evaluated through ball on disk wear testing method. Testing was carried out at three different loads, i.e., 30, 40, and 50 N to understand the wear behavior at different loading conditions. The wear resistance of the spheroidized high carbon steel (0.7%) is found to be lesser than that of steels containing pearlite in their microstructures, i.e., low carbon (0.19%) steel and medium carbon (0.32%) steel. Enhanced strain hardening of the pearlite structure was held responsible for the increased wear resistance. As expected if steel showed least wear resistance due to its softer ferrite content. The SEM images of the worn structures are correlated with the macroscopic wear resistance data.

Laser beam welding (LBW) is extensively being used in modern industry for joining of metals and alloys due to its advantages of controlled heating, narrow weld bead, low heat-affected zone (HAZ). Further, its ability is to weld a wide range of metals and dissimilar metals. With a new generation of high power lasers, LBW makes the process possible for welding of dissimilar metals used in shipbuilding, offshore structures, pipelines, power plants and other industries. In addition, LBW is suitable for joining at high process speed, low heat input to achieve high productivity, leading to reduced process costs. Therefore, an attempt is made in the present paper with an objective to investigate the mechanical properties of dissimilar metal joints of AISI 4130 and AISI 316 steels. Experiments are conducted with LBW considering 2-mm-thick dissimilar metals by varying laser beam power, welding speed, beam incident angle, focal point position and focal length. The experimental output results of ultimate tensile strength and impact strength are measured. ANOVA is carried out to obtain the influence of process parameters and validation of results by statistical analysis. Firefly optimization algorithm is used to determine the best combination of the process parameters of LBW.

In this paper, an experimental study of electrical -discharge grinding (EDG) process of Ti–6Al–4V alloy on material removal rate (MRR) and surface roughness (SR) through response surface methodology (RSM). Wheel speed (WS), discharge current (Ip), pulse on time (Ton), and pulse off time (Toff) are considered the important parameter. RSM-central composite design (CCD) of four parameters with three levels has been employed. ANOVA results were performed to identify the significant parameters and the establishment of the mathematical model of MRR and SR. Furthermore, mathematical models and experimental values were correlated; the results were verified and found to be within the range of 7.57% and 4.68% of MRR and SR, respectively.

In today’s world, to meet the requirements of the extreme applications, the need for precisely manufactured components becomes necessary. The new materials developed for the extreme applications are difficult to machine by conventional machining processes due to their high hardness. Most of the materials irrespective of their hardness can be easily machined by EDM. In this present work, a prediction model for MRR in machining of Hastelloy C276 on EDM using Buckingham Pi theorem is developed to study the influence of process parameters. Further, the linear programming using MS-solver was applied to perform the optimization and the sensitivity analysis for the model developed. The theoretical and experimental results are compared and found that the predicted model results are satisfactory.

In this paper, exfoliated vermiculite (EV), a siliceous non-metallic particle is used as both thickening and foaming agent to fabricate low-density metal foam via the oxidation reduction method. Aluminium Alloy 5083 is used as base metal. EV particles 0.1 mm size that were dehydrated by preheating were added as thickening agents and EV particles 1 mm size containing 5% moisture are used as foaming agent to produce bubbles. The density of the foam produced is reduced by about 50% when compared to pure Al5083. The macrostructure reveals that 1.5% EV particle addition resulted in uniform foam. Average pore size varied from 0.1 to 2 mm with varying EV %. With an increase in amount of thickening agent percentage, the pore size decreased, but when the thickening agent increased beyond 1.5%, the pores size increased. The density of foam increased with increase in percentage of thickening agent. From the compressive stress–strain curves, at strain rate of 1 mm/min, the plateau stress increased with the density. The energy absorption for the foam is found to be 4 MJ/m3 for 1.5% EV particles. The energy absorption efficiency is 65%.

The present study focuses on multi-response optimality of machining parameter using grey relational analysis combined with principal component analysis coupled with Taguchi SN ratios. The responses like roughness and hardness of the machined surface are considered for study while machining in tangential and orthogonal turn-milling processes. Subsequently, study of individual optimality and empirical regression modelling of machining parameters like end mill cutter (tool) speed, rate of feed and depth of cut on responses are also carried on. A-axis CNC Vertical Milling centre is considered for the process of single cut plain turning operations using high-speed steel end mill cutters. Brass rods material is taken as work material under dry condition. Experimentation results show that tangential turn-milling is more efficient than orthogonal turn-milling in generating the responses for same machining parameter combinations.

This work deals with the application of amylum additive-based cutting fluids while turning AISI 304 steel using carbide inserts. Amylum additive is dispersed in vegetable oil at varying percentages. Absorbance of the additive in pure bio-oil is examined using spectrophotometer, and thermal conductivity of these formulations is also obtained. Machining performance is assessed by comparing dry, synthetic cutting fluid, and pure oil for fixed cutting conditions. After basic machining, percentage of amylum additive is changed, and machining is done to examine the best concentration (0.3–0.9%) of additive in pure oil through minimal quantity lubrication technique. Machining performance is obtained by measuring cutting tool temperatures, surface roughness, and tool flank wear. It is inferred that, when compared to dry machining, synthetic fluid, and pure oil-assisted machining, amylum-assisted cutting fluids have resulted in improved machining performance owing to the reduction in cutting temperatures and better lubricity. Hence, it can be comprehended that amylum additive has the potential to be used as an additive in biodegradable oils in view of eco-friendly and user compatible machining operations.

The present paper reports the uniaxial tensile property of fibre and laminated composite of Dyneema® HB80 prepreg under quasi-static conditions. A detailed experimental work on tensile testing of fibre/filament and its laminated composite has been presented. It has also been discussed about the easy slipping out problem of Dyneema® grade test specimen during experimental work. The tensile strength of the filament of Dyneema® HB80 has been evaluated and found to be 2.96 GPa with an average elongation of 4.15%, closely agreed with the test data of manufacturer, although tensile strength of laminated composite has been found quite low as compared to fibre tensile strength. The effect of curing temperature on the tensile strength has also been studied and found higher strength for the laminate cured at a comparatively lower temperature. The SEM analysis of the fractured samples showed weak macro fibrils resulted in higher degree of damage to the fibre laminate, and hence, lower tensile strength.

Electrochemical micromachining (ECMM) is a nontraditional machining technique in the area of mechanical engineering. It is more essential to meet the increasing demand of the industries from aero to medical. ECMM is the promising technique, since it has been growing popularity in various areas of applications. In the present study, the optimal combination and influence of process parameters on ECMM while machining Al 7075 T6 alloy are presented using Taguchi analysis and ANOVA. A bare electrode (cathode) has been used for this purpose. Later on, using an optimum combination of process parameters, the hole is drilled with insulated electrode. The ECMM process model has been developed and simulated with a bare tool and insulated tool using COMSOL Multiphysics V5.3a software. The effect of tip reaction on anode profile and stray current machined zone is identified with the electric field, temperature field, and fluid field. The results are validated with experimental results. The simulated predicted model is in close conformity with an experimental model.

The aim of this paper is to study the performance of coated tools in machining with multilayer coatings. The coatings are made usually by using PVD or CVD techniques, and the coating material should be in such a way that it should make a very strong bond with the base material. In this paper, FEM model is developed by considering workpiece as AISI 1045 and tool as three-layered (TiC/Al2O3/TiN) coated tungsten carbide. Deform 2D software is used to simulate the model. Initially, the model is simulated at a different feed rate to observe the temperature distributions, and then, outcomes are compared with the experimental values to validate the model. After ensuring the accuracy of the developed model, the performance of tungsten carbide coated tool is studied by using this model. The influence of coating thickness is observed at the same machining conditions. Cutting forces, cutting temperature and effective strains are measured for all the combination of coatings selected in this study.

Cutting fluids have superior convective and conductive heat transfer coefficient, good lubrication and better chip removal rate from the cutting zone. But when applied in large quantities, as flood machining, its treatment, and disposal increase the economic burden on industries. Application of just sufficient quantity of cutting fluid exactly at the cutting zone as Minimum Quantity Lubrication (MQL) is found to be an alternative approach to flood machining. But it requires the use of cutting fluids with enhanced properties. Researchers suggested that nanofluid is the latest concept to achieve high performance of cooling and lubrication effect in machining. This project mainly focuses on performance evaluation of Minimum Quantity Lubrication (MQL) application of graphene nano cutting fluid while turning Inconel 718 alloy at constant cutting conditions. Different weight proportions (0.1wt%, 0.3wt%, 0.5wt%) of graphene are mixed with soluble oil using TX 100 as a surfactant. Machining performance is evaluated by measuring cutting forces, cutting temperature, surface roughness and tool wear. Performance is compared with dry machining and MQL application of cutting fluid without graphene.

Zircon reinforced composites are referred as a unique composite that exhibits relatively improved mechanical properties like high tensile strength and micro hardness compared to pure AA 7075 base metal. The present work aims to investigate that influence of reinforcement of ZrO2 nanoparticles are mechanical properties of AA 7075 alloy and composites prepared through stir casting method. Samples are fabricated through varying the weight percentage of ZrO2 2 and 4 wt%. Mechanical properties of AA 7075 and composites were observed in particulars of density, porosity, micro hardness, XRD of ZrO2 and tensile properties. Increased reinforcement contents enhance 15.92% of micro hardness, and 28.46% of tensile strength was noticed. However, the increase of particle concentration of reinforcement leads to diminishing of the percentage elongation.

Lightweight thermoplastics are the most prominent concerns of manufacturers due to their high performance characteristics in the current trend. Weld strength and weld quality are the performance measures of the thermoplastic materials, and determining the optimum weld parameters is the major research problem. This paper presents the optimization of weld parameters required for friction stir welding (FSW) of silicon carbide and aluminum reinforced in high-density polyethylene. The improved mechanical properties of these composites are the resultant effects of the optimum process parameters like welding speed, rotational speed, tilt angle, and percentage of reinforcement; hence it is very essential to determine them and to study their influence on composites weld joint. The experimental analysis was carried out for three levels in each and different combinations of weld parameters in order to measure the tensile strength and hardness. The optimum set of nine experiments was designed based on L9 Taguchi’s design. The elicited test results convey that rotation speed of the tool is the most influential weld parameter for tensile strength and weld speed is the most responsible for hardness response of FSW butt joint. Maximum weld strength is 74.66% of the base material and hardness of 41.90 BHN at the weld portion is obtained. The analysis reveals that the added silicon carbide and aluminum particles enhance the ductility and brittle characteristics to base HDPE sheet causing improved weld strength and in turn ensures the weld quality.

This paper presents the efforts made in the design and finite element simulation of porous Ti–6Al–4V alloy structures to determine the elastic modulus of porous parts produced with the additive manufacturing technology for biomedical applications. The major problem concerning with the typically used metallic bioimplants is the mismatch of elastic modulus between the implant and the human bone, which resulted in the degradation of surrounding bone structure and disassociation of the implant. The present work is focused on designing the porous Ti–6Al–4V alloy structures and also on studying the influence of porosity on the elastic modulus of implants made of Ti–6Al–4V alloy material. The three-dimensional strut-based cellular structure is employed to build the porous structures ranging from 10 to 50% porosity volume. This work established the appropriate porosity to minimize the mismatch of elastic modulus between the implant and the bone by adding the porosity to the implant structure. It is found that the Ti–6Al–4V structure with the porosity of 40 vol.% possesses the elastic modulus about 74 GPa. These results demonstrate the proof of tailoring the elastic modulus of bioimplants.

In this study, AA6061 plates of 6 mm thickness were subjected to friction stir processing with 50% pin overlapping to produce bulk area fine grain structure using three different tool geometries. Post-processing heat treatment was carried for all samples to investigate the effect of different tool geometries on microstructure and micro-hardness of AA6061. 3D optical microscope and Vickers micro-hardness tester were employed to examine the microstructure and micro-hardness, and results have been reported. From an analysis, it was observed that post-processing heat treatment improved the properties and among three different tool geometries, the samples processed with the hexagonal pin profile yield the best results.

In spite of huge advancement in machining process and much promising surface integrity, die-sinking EDM process is unavoidable. Micro-crack formation in the white layer zone in EDM leads to damage the quality of machined surface. This paper furnishes a quantitative investigation of micro-crack formation, in terms of crack width and orientation of micro-cracks formed in the white layer zone. The impact of processing conditions like peak current (Ip) and pulse on duration (Ton) on crack formation is examined by utilizing the perceptions of scanning electron microscope (SEM). In this work, micro-hardness is measured at different zones that are deposited layer, heat-affected zone (HAZ) and base metal. It is observed that significant improvement in the hardness value of the recast layer (9.175 Gpa) as compared to base metal (3.115 Gpa) of M2 die steel.

Submerged friction stir welding (SFSW) is a moderation tool in the manufacturing industry. SFSW is used to join the AA6061-T6 plates in the seawater environment to different processes of parameters that are tool rotation speed, feed rate, and tilt angle. The experiments are done by using optimization method. To obtain a single optimum combination of parameters for these two types of responses, gray relational analysis has been utilized. Gray relational grade and a single optimum setting have been acquired for the SFSW of AA6061-T6. One of the most affecting and influencing processes of parameter is to find by applying ANOVA and the maximum orderly tool rotational speed is 61.63%, tool feed rate is 17.95% and finally, tool tilt angle is 12.47% of contribution in the entire process.

This project aims to increase the wear resistance of aluminium alloy 5052 (AA5052), which has very good corrosion resistance, ductility, excellent thermal and electrical conductivity. Composites were fabricated using AA5052 reinforced with silicon carbide 3% and alumina 3 & 4% by weight of the matrix, melting temperature 700 & 750 °C and stirring time 3 & 5 min. Maximum micro-hardness and tensile Strength were achieved for the combination of silicon carbide—3%, alumina—4%, melting temperature—750 °C and stirring time—3 min. Composite fabricated for the above said condition is used for wear analysis. The design of experiments was planned in full factorial method with load, speed, time and track diameter as input factors and wear as the response or output factor. The test was performed in pin-on-disc tribometer as per design of experiments. The process parameter combination of 2 kg load, 500 rpm speed, 5 min time and 70 cm track diameter was found to be the optimum condition for minimum wear of the fabricated hybrid composite. Wear resistance was increased by 51%. Speed has the maximum influence with 45.52% contribution, whereas time has the least influence with 7.02% contribution.

High energy density beam-assisted machining (HEDBAM) finds huge applications in machining of difficult-to-machine materials such as hardened steels and super alloys. Among these materials, armour steel is widely deployed in military and civil applications where resistance to ballistic protection is essential. In the present work, a numerical model is developed to investigate HEDBAM of high hardness armour steel. A fully coupled thermo-mechanical analysis model is developed for predicting the cutting forces and thrust forces using commercial software Abaqus/Explicit. The developed model for orthogonal cutting is validated with previously published literature on thermally assisted machining of titanium alloy with a maximum error of 9%. Further, the model is extended to of armour steel at four different temperature levels (20, 220, 420 and 620 °C), and a maximum reduction in 19 and 24% in the cutting and thrust force, respectively, is obtained at 620 °C. The work paves way for HEDBAM of different hardened high strength materials.

Electro-discharge machining (EDM) is one of the most popular advanced machining processes for machining conductive material irrespective of material physical properties. In the present study, effect of electro-discharge machining parameters such as current (A), pulse on time (Ton) and pulse off time (Toff) on machining characteristics such as material removal rate (MRR), tool wear rate (TWR) and surface roughness (SR) of NIMONIC 80A is focused. The Box–Behnken design (BBD) of response surface methodology (RSM) was used to design the experiments, and also, analysis of variance (ANOVA) was conducted in order to know the most significant parameters. ANOVA results show that current and pulse on time were the most significant factors for material removal rate, and only current was significant parameter for tool wear rate and surface roughness. Multi-objective optimization process was conducted to maximize the MRR and to minimize the TWR and SR, and optimized parameters are “3 A” current, “900 µs” pulse on time and “30 µs” pulse off time with the desirability value of 0.988.

Cutting fluids are inevitable in manufacturing industries due to their cooling and lubricating properties. But their applications in large quantities pose serious threat to biological bodies in the oceans and rivers when disposed untreated. Strict rules and fines imposed by most of the countries on such industries created an economic and environmental concern. This led to research in finding alternative methods to either eliminate or reduce the usage of cutting fluids. Minimum quantity lubrication (MQL) is one of such methods being widely tested to replace flood machining. Application of cutting fluid as MQL requires decision of choosing the optimum MQL parameters, i.e., air pressure, cross-sectional area of nozzle and coolant flow rate. The present paper deals with optimizing these MQL system parameters in order to minimize cutting forces and surface roughness using conventional soluble oil as coolant. Coolant flow rate and quantity of air supplied were found to contribute the most to cutting forces and surface roughness, respectively.

Boron carbide (B4C) particulate Aluminum (Al) metal matrix composites (MMCs) are highly demanded due to their specific strength in aerospace, defense, and nuclear sectors. The controllable porosity which causes the good toughness and the forming limit values can be obtained for these MMCs synthesized by powder metallurgy route. But the porosity level had great influence on the machinability of these MMCs by electric discharge machining (EDM). In the present work, cold compaction followed by sintering of Al and B4C powders was used to fabricate the MMC specimen. The density and hardness were estimated by Archimedes principle and Vickers microhardness test, respectively. The feasibility of EDM of the fabricated MMC at high porosity level (12%) was evaluated through pilot experimental runs. The full factorial experimental design with three parameters of three levels each (total runs 33 = 27) is used for experimentation. The influence of electrical process conditions such as discharge current (I), pulse-on duration (T-On), and pulse-off duration (T-Off) on material removal rate (MRR) and tool wear rate (TWR) was studied. A mathematical model was formulated to represent the process. Analysis of variance (ANOVA) was performed to identify the significant parameters affecting the material removal rate (MRR) and tool wear rate (TWR). Results revealed that the developed model was adequate to represent the process with R-square values of 94.9%, and 83.82% for MRR and TWR, respectively. Results also showed that the discharge current had a significant effect on the MRR and TWR.

Friction stir welding (FSW) is an effective technique to join magnesium-based alloys which are difficult to fusion weld. In this work, similar AZ91D Mg alloy sheet of 3 mm thick butt joint was produced via friction stir welding at welding parameters such as rotational speed, welding speed, and tilt angle. The rotational speed was kept constant of 720 rpm, the welding speed varied from 25 to 75 mm/min, and tilt angle from 1.5° to 2.5°. Defect-free weld was obtained under 75 mm/min welding speed and tilt angle of 1.5°. The microstructure of the parent alloy consists of phases, namely primary α and eutectic β (Mg17Al12) in the as-received condition (gravity die-cast) which was confirmed by X-ray diffraction (XRD) analysis. Microscopic studies, tensile tests, hardness test, and fractographic studies were conducted. Metallographic studies revealed different features in each zone depending on their thermomechanical condition. A significant increase in hardness was observed in the stir zone of weldment compared to parent alloy due to the recrystallized grain structure. The dendrite grain structure present in weldment was completely disappeared and was transformed to fine grains in stir zone (SZ). The transverse tensile test result of the weld specimen indicated that weldment was about 44.9% higher than the parent alloy. Fractographic analysis of the friction stir welded specimen indicated that the weld specimen failed through the brittle failure.

Natural fibers are playing very important role in supporting the environmental balance and partially substitute to the structural applications. In this paper, hybrid composites are fabricated using unidirectional banana and unidirectional glass fibers into epoxy resin mixture. Percentage weight of unidirectional banana fibers considered in this study is varied from zero to 100% weight of fibers in the intervals of 20% weight of the total fibers. The objective of the present work is to evaluate and compare the mechanical properties of laminates such as tensile strength, flexural strength, and impact strength of different stacking sequences of unidirectional banana and glass fabrics. It is found that as the glass layer in the laminates increases, its mechanical properties enhance. When the natural fiber is hybridized with glass fiber, a moderate strength is observed in the composites. These hybrid composites can be used for medium load-bearing applications.

Automated ultrasonic testing method will be used in the many industries to locate discontinuities and to detect internal defects under test inside the workpiece material. The lowest defect size in weld material may start from 0.5 mm onwards. Ultrasonic testing is a fast and automated method, because the signals are available in electronic form to be tested in plates and pipes. This is mainly used for whether the material will be accepted or rejected easily based on internal cracks. “Modsonic Einstein II TFT (MODSONIC)” software package has been extensively using in many industries to find flaws and cracks. The objective of the work is to find the flaws in various materials like mild steel (M.S) plate clad with mild steel (M.S) electrode, mild steel plate clad with brass electrode, mild steel plate clad with stainless steel electrode, mild steel pipe clad with mild steel electrode. To detect the flaws at various angles, the probes are placed at 45°, 60° and 70°. When the size of the weld plate is less than 25 mm, then it will be preferable to use and find flaws in materials with 70° probe angle. With MODSONIC software package, it is found that mild steel pipe welded with mild steel electrode highlighted more internal flaws at 70° probe angle from experimental analysis.

The formation of the dead metal zone (DMZ) in equal channel angular extrusion (ECAE) process significantly affects the deformation uniformity and mechanical properties of work material. The aim of the present study is to investigate the effect of the dead metal zone on structural homogeneity and hardness of Al 5083 alloy processed by ECAE and suggest the way to minimize that adverse effect. In this work, the rectangular billets with 1-mm-thick copper casing on two longitudinal faces and square billets with no casing are processed by ECAE up to four passes in route A. It was observed that the soft and ductile nature of the copper casing allows smooth flow of the work material at low pressing loads as compared to the alloy ECAE’d without a casing. Field emission scanning electron microscope (FESEM) images of the processed material with casing show the noteworthy improvement in structural homogeneity and grain refinement than another set of billets. The obtained structural homogeneity indicates the uniform strain distribution in the processed material is achieved by minimizing the formation of the dead metal zone at the intersection of ECAE die channels. The higher hardness and tensile strength measurements of the processed materials indicate the significance of grain refinement and uniform strain distribution. The variations in the test results confirm the non-homogeneous strain distribution caused by the dead metal zone is high for the billets processed with no copper casing.

This paper examines the influence of hybridization on mechanical and thermal properties of biocomposites. Kenaf and Aloevera fibers were treated by NaOH treatment to improve the bonding with Polylactic acid. Kenaf (30 wt%) reinforced Polylactic acid (70 wt%) and Aloevera (30 wt%) reinforced Polylactic acid (70 wt%) biocomposites, and Kenaf/Aloevera (15/15 wt%) reinforced Polylactic acid (70 wt%) hybrid biocomposite are prepared by extruder and compression molding process. The fabricated bio and hybrid biocomposites were used to illustrate the impact and thermal properties of biocomposites. Treated Kenaf/Aloevera fiber (15/15 wt%) reinforced Polylactic acid (70 wt%) hybrid biocomposite exhibits higher mechanical and thermal properties than other biocomposites.

Electric discharge machining (EDM) is used to produce complex geometries from difficult-to-cut materials in the area of making dies, mold, and tools. Complex geometries involve different shapes, and electrode plays a major role in reproducing the shape on component. In EDM, hydrocarbon oil-based dielectric fluid is used which is causing environmental issues. Recently, researchers attempted by using vegetable oil as dielectric fluid in EDM process which is a natural product and lead to sustainability in machining. In this analysis, machining performance of different cross sections of electrode is analyzed with vegetable oil (sunflower oil) as dielectric fluid, and the results are compared with conventional dielectric fluid (kerosene). The different cross sections of electrode used in the work include circle, square, rectangle, and hexagon. Material removal rate (MRR), tool wear rate (TWR), and surface roughness (SR) are observed with two sets of energy levels during the process. The result observed that vegetable oil has similar dielectric properties and erosion mechanism compared with conventional dielectric, and it could be used as dielectric fluid in EDM process.

There was a remarkable increase in the mechanical properties and fracture toughness by using chills during the development of composites. In the present work, metallic and non-metallic chills were used to develop the LM13 alloy-fused SiO2 metal matrix composite reinforcement which varied from 3 to 12%, in steps of 3%. The fracture toughness experiment revealed a toughness of 9.7 Mpa√m for the composite with 9 wt%. Beyond 9 wt%, the fracture toughness declined. The increase in the fracture toughness can be attributed to uniform distribution of the hard reinforcement particles.SEM fractography of fracture toughness specimen reveals that the matrix alloy exhibits fine and shallow dimples with high plastic deformation, thus clearly indicating that the type of fracture is ductile. For validity purpose, the experimental results of the fracture toughness were assessed through FE analysis and found that the results are converging within the limits, i.e. 5%.

The centrifugal die casting process was observed at VACPL, at Vijayawada in India. In the present observation, for the production of cylinder liners, resin sand was used at the front door of the centrifugal die casting machine, and also, resin sand was dressed at the inner surface of the die. However, no resin sand is used at the back door, which results in the direct melt to metal contact at the back door and which increases the hardness of the casting excess than required, due to rapid cooling rate between the casting and die back door zone. Due to this hot spot, defects appear on the back door, and it decreases life of the back door and increases the scrap rate. The chilling length is removed by the parting operation, which increases the cost of production. In this research work, to eliminate that hot spot defect, the die back door was design and fabricated to introduce resin sand, and also, the temperature distributions of the die back doors were simulated by using ANSYS 18 software. Both old and new rear-end casting samples can be examined using the FE-SEM and EDX technique for microanalysis. Result in, no direct metal to metal contact, increasing the life of back door and the hardness of the cylinder casting is limited to as per requirement, parting operation and hot spot defects are eliminated. Instead of parting operation, facing operation is adopted. The time required for facing operation is 1/6th of the parting operation.

Functionally graded materials (FGM) are the composite materials that are heterogeneous wherein the compositions or microstructures vary locally resulting in certain variation in the local material properties. Moreover, certain challenges exist in their manufacturing techniques. In this study, functionally graded composites were manufactured by integrating SiC particles of particle size: 20–30 μm in a groove on aluminium alloy 6082-T6 plate using friction stir processing (FSP) route. Three sets of samples with variation in a volume percentage of SiC along the thickness were processed by one to three passes. The effect of multipass on microstructure, microhardness and wear behaviour of graded materials has been analszed. The functionally graded composite layer produced with three FSP passes has shown the superior wear resistance of 0.25 mm3/m; that is, because of its greater microhardness value of 110 HV which is 1.8 times greater than the base metal. The modifications were mainly because of microstructural alterations through FSP, better particle dispersion, decreased particle clustering and fine grain size (6.39 μm).

In many industries, alloys of nickel have extensive range of applications for their noteworthy properties like corrosion resistance, high temperature tolerance and resistance to creep rupture. Nickel-chromium (Ni 690) alloys being precipitation hardenable are broadly employed in aircraft structures, gas turbines, rocket engine thrust chambers, pressure vessels and nuclear reactors. Machining of Inconel 690 is very hard by traditional routes because of their strong strain hardening nature, poor thermal conductivity and high strengths at very high temperatures. EDM has a thermal process which can be used irrespective of workpiece strength and hardness, to machine Inconel 690 alloy by electrical erosion. In this paper, the investigation of chosen input parameters current (Ip), pulse on time (Ton), gap voltage (V) and pulse off time (Toff) of EDM on Ni-690 alloy on resulting process parameters like surface roughness (SR) and material removal rate (MRR) is considered. Primarily, the experiments were planned and designed with RSM-CCD approach. Grey relational analysis (GRA) was adapted to multi optimize the performance parameters on MRR and SR. In further stages, analysis of variance (ANOVA) approach was selected to reveal the impact of the variables on the performance characteristics of SR and MRR. GRA results show that the EDM performance in the Ni-690 machining process can be improved at confirmation test conditions.

Effect of aluminium oxide nanoparticles (Al2O3 NPs) was studied on the microstructural and mechanical properties of friction stir welded 2014 aluminium alloy to overcome softening in nugget zone. A joint with and without Al2O3 NPs was welded to compare the microstructure, tensile and hardness results. Optical and scanning electron microscope (SEM) was used for investigation of distribution, grain size and grain structure in the stir zone. Transverse tensile test and hardness across the weld surface were carried out to compare the mechanical properties of the joints. The FSW parameters fixed throughout the experiments were 1100 rpm, 30 mm/min of rotation speed and traverse speed, respectively. Microstructure observation indicated that the Al2O3 NPs were distributed uniformly after the third pass and the Al2O3 NPs settled at the grain boundaries in the stir zone which leads to an increase in the weld strength. The grain refinement was successfully achieved after reinforcing nanoparticles in the stir zone of FSW joint. The tensile strength of reinforced FSW joint got enhanced about 22% to that of normal FSW joint. Due to a decrease in grain size and the presence of nanoparticles in the stir zone, the average hardness across the stir zone of the reinforced joint was improved.

Inconel 718 alloy is, in exacting superalloy, used extensively in the most sophisticated application such as aerospace, chemical, marine and high-speed racing cars. However, the characteristics of this material make it difficult to machine due to poor thermal conductivity (11 W/mK) and work hardening. The turning process is classified as a process that produces continuous chips and experiences elevated temperatures. With emerging new and efficient MQL delivery systems, the industry has shown drift from flood and dry lubrications towards MQL. Having this in mind, to further improve the cutting fluids, a novel hybrid nanocomposite of Cu–Zn was developed in situ with mechanical alloying. Cu–Zn/vegetable oil (groundnut oil) hybrid nanofluids were prepared by dispersing the synthesized nanocomposite powder in vegetable oil. A unist MQL system combined with a compressor is used to supply nanofluid mist to the cutting zone. The inserts used were TiAlN coated beyond blast insert from Kennametal with ISO designation CNGG 120408. The insert holder used was from Kennametal beyond blast with ISO designation MCLNL 2525 M12BB. The intent of this work is to haul out the effect of cutting parameters like speed, feed, depth of cut, volume of fluid and air pressure, when machined under dry, MQL/vegetable oil and MQL/nanofluid conditions. The results were compared while machining with dry and Veg/MQL lubricating conditions. A 39% reduction in surface roughness was obtained when compared to dry machining.

This study focuses on the prediction of cutting force, tool flank wear and surface roughness with extreme pressure (EP) additive included vegetable-based cutting fluids (VBCFs) using fuzzy logic and regression. Cutting force, tool flank wear and surface roughness are measured during turning of AISI 1040 steel according to L9 orthogonal array. A model depends on fuzzy logic is established, and the results obtained from fuzzy logic are compared with the results from regression and experimentation. Fuzzy logic model gives closer values to experimental results than the regression model. It has been concluded that fuzzy rule-based modelling helps in predicting cutting force, surface roughness and tool flank wear. Confirmation experiment results revealed that fuzzy logic model is better than regression model for predicting cutting force, tool wear and surface roughness in turning.

Sensors have become an integral part of the current manufacturing systems. However, gaining insight into the data collected from sensors is a complex task. The current paper presents an approach to identify stable machining parameters by applying frame statistics and kurtosis to cutting force signal. The approach is presented in finish turning of aluminum metal matrix composites (Al-MMC) using coated carbide inserts. It was found that the process parameters suitable for finish turning Al-MMC are 80 m/min cutting speed, 0.103 mm/rev feed and 0.1 mm depth of cut. The approach presented can be applied to other machining processes, and as it is computationally efficient, it can be used in online monitoring systems.

Garbage management is a continually growing problem both at global and regional frontiers. Solid waste arises from human, animal, and industrial activities. User-friendly products are essential for garbage collectors and residents to improve the utility. In this study, the main concerns are addressed to design an economically frugal garbage transportation cart which would be viable for commercialization. The new design is engineered keeping in mind present-day conditions and is built to cater to the needs of the pourakarmikas. The ease of operation of the proposed model will increase efficiency by reducing effort and hence the fatigue on the operator. The revolutionary changes that are proposed to be incorporated in the new model are as simple as replacing steel with aluminum where ever necessary, yet having a significant impact on the overall ergonomics. Other such pivotal changes are equipping the cart with an economic motor and a battery to provide assistance in maneuvering the cart on challenging terrain. Also, a braking system is proposed to be integrated into the cart to prevent undue movement of the cart. A turntable to make the bins instantly accessible is also added which reduces the time while loading and unloading of garbage.

The important element to meet today’s competitive market during the development of any product is the reduction of assembling time. The industries which use a variety of component geometry Design For Manufacturing and Assembly (DFMA) play a vital role in product development. Design for Assembly (DFA) is one of the principles in DFMA. The principle concept of DFA is to reduce the number of parts used and to maximize the use of existing parts and to eliminate or redesign the parts which take more assembly time. Many of the companies successfully used this technique for product design improvement. The aim of the present work is to propose a new design of electric plug assembly that is better in design efficiency, total assembly time. The analysis is done by using Boothroyd Dewhurst DFA method. There is a reduction in the number of parts from 16 to 11 after redesign of electric plug assembly and assembly time is reduced from 87.4 to 33.9 s. Design efficiency is improved from 36 to 64.89%. In product development, reducing assembly time is one of the important tasks because it reduces labor time. Simple design with least number of components makes assembly easy and fast.

The objective of this paper is to present an authentic queuing scenario for airports both international and domestic including transit passengers in constant efforts to create a uniform flow of passengers and baggage. This study aims also at the simulation that can be used to identify bottlenecks in the systems as well as to gain insight into the whole process. Similarly, the study suggests multiple modified scenarios that provide a solution to the challenges in existing systems that can be adopted by the industry in the near future. More specifically, these scenarios are rearrangements and modifications to the existing system. As security checkpoints are points in the system which can cause severe delays and are notorious for separation of individuals in a group. Therefore, scenarios are considered wherein the number of checkpoints can be increased such that the total number of individuals waiting gets distributed effectively. Lastly, another scenario in which gate specific checkpoints are considered has been modeled for reference and can be seen on a few busy airports, it was also observed that the waiting times at security checkpoints reduced by 0.10 out of 0.43, 0.07 and 0.33. Though a longer queue time was observed at the last scenario than the second scenario, the third scenario would be a better replacement as it yields an optimum performance time without increasing the load on other points such as immigration, check-in and baggage claim unlike the second scenario wherein the queuing at security check point is reduced but pressure builds up on other parts of the system.

Inventory management is the heart of manufacturing industry because proper inventory management leads to major cut back in the operating costs. Several researchers had focused on this issue because of its importance in cost reductions. Lot of traditional, nontraditional and heuristic algorithms were developed to solve this problem with good solution efficiency and computational effectiveness. In this paper authors are trying to explain about the research in the area of inventory management especially in the Lot sizing of inventory techniques from 1913 to 2018 and different soft computing techniques Like Particle swarm optimization and Harmonic Search were applied to Multi-Level Capacitated Lot sizing problem and they were compared with the different algorithms from the previous literature.