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This paper summarizes the complex unsteady, 3-D viscous flow aerodynamics (dominantly laminar) developed in flapping wing generating vortices and intersecting with them. Different flying creatures, (Insects, Birds, and Bats) flapping wing mechanisms are studied and hence being compared based on their wing kinematics and aerodynamic efficiency. The performance of low Reynolds number flyers is highly influenced by the wing shape, wing size, wing camber, aspect ratio, % camber thickness, elastic deformation, wing-beat frequency and wing twisting. The Computation technique used to analyze the wake characteristics of a flapping motion shows that the generation and shedding of vortices dominate the aerodynamic loading on the wing. The periodicity of the wing motion and the resultant vortices leads to conclude that any quantitative model must be based on unsteady aerodynamics and vortex dynamics.

The present numerical study investigates the design and analysis of a concept model Le Mans Grand Touring Prototype (LMGTP) car. Through analysis, aerodynamic pitch sensitivity and related factors are found to be detrimental to the straight-line stability of these high-speed race cars. Simulations are carried out on a commercial Computational Fluid Dynamics (CFD) tool for varying pitch angles of the car from −1° to +2.5°. For each pitch angle, steady-state pressure contours, velocity contours, and streamlines are presented. Additionally, coefficients and force values of lift and drag are calculated with the k-omega turbulence model implemented. Obtained numerical results are validated via Ahmed Body studies reported in the literature, and an average error deviation of 1.013% is exhibited. It is observed that lift force at the front axle increases with increasing pitch angles, leading to reduced pitch stability.

Nickel based superalloys have a wide range of applications due to high mechanical strength at high temperatures, fracture toughness and resistance to corrosion. However, because of their outstanding properties, it is considered as the difficult to machine materials. Inconel alloy X-750 is used extensively in rocket-engine thrust chambers. Airframe applications include thrust reversers and hot-air ducting systems along with large pressure vessels are formed from Inconel alloy X-750. Moreover, the comparative analysis of machinability aspect using coated carbide inserts is reported few. The current study explains the machinability investigation on Inconel alloy X-750 superalloys using coated carbides. To collect the experimental data, the L16 experimental design plan is used to experiment with a machining length of 40 mm.

In the fabrication of parts in auto and aero segments, the use of ceramic (SiCp, Al2O3p) reinforces aluminum alloy found to be increased than that of steel and cast iron. This matrix-reinforced alloy has a high strength to weight ratio along with higher modulus and hardness, the lower thermal coefficient of expansion, and improved tribological properties. To this extent, this paper investigates the turning characteristics and optimization study of newly developed metal matrix composites by the addition of both hard ceramic SiCp and soft stable lubricant molybdenum disulfide (MoS2p). The samples such as Sample 1: AlSi10Mg/3SiCp, Sample 2: AlSi10Mg/2MoS2p and Sample 3: AlSi10Mg/3SiCp /2MoS2p are prepared using the automated stir-casting machine. The particles are observed to be uniformly distributed in the composite. After density and hardness measurement, the samples are subjected to machining, and the responses are optimized by using response surface method.

Epoxy carbon fiber composite materials are known for their light weight and high performance. They can be effective substitutes for commonly used materials for making drive shafts. Fiber orientation angle plays a major role in determining such a drive shaft’s responses. The responses considered in this paper are critical buckling torque, fundamental natural frequency and total deformation. A drive shaft made of epoxy carbon unidirectional prepreg is generated using ANSYS 18.0 ACP Composite Prepost. The objective of this paper is to determine an optimal configuration of fiber orientation angles for four, five and six-layered epoxy carbon drive shaft which tends to increase critical buckling torque and fundamental natural frequency while decreasing the total deformation. The optimal configuration which satisfies this objective for the three responses is identified by Minitab 17 statistical software.

This paper summarizes the research work incorporated in the exploration of the potential of swirling in CI Engine and designing of a new mechanism, particularly at inlet, to deliver it to improve the in-cylinder air characteristics to eventually improve mixing and combustion process to improve the engine performance. The research is concentrated on the measures to be done on engine geometry so as to not only deliver advantage to any specific fuel. According to the CI combustion theory, better engine performance may be achieved with Higher Viscous Fuel by improving the in-cylinder air-fuel mixing by increasing the swirl (rotation of air view from top of the cylinder) and tumble (rotation of air view from front of the cylinder) of in-cylinder air inside the fuel-injected region. The proposed inlet component is embedded with airfoil and is suitably designed after being iterated from four steps.

A well-established method of surface roughness measurement is of stylus-based. The filtering effect of the stylus tip is the major lacuna of the process. So in the present study, a vision based 100% inspection procedure is proposed for the characterization of ground specimens. A CMOS camera, and monochromatic line laser source were used for capturing speckle line images of the ground specimens. Signal vectors were generated from each of the surface images of ground specimens using MATLAB software. On the other hand the roughness of the ground specimens, particularly the Arithmetic roughness average (Ra) & Arithmetic mean slope (Rda) were computed using a stylus instrument. It was found that standard deviation and kurtosis having good correlation with the image pixel intensity of the signal vectors with the correlation coefficient of 0.96 & 0.89 for Ra and 0.86 & 0.82 for Rda respectively.

Considerable weight of an automobile is constituted by the engine and there is scope for improvement in fuel efficiency and emission control through optimization of weight in the engine. In this work, AlSi10Mg alloy produced by the direct metal laser sintering (DMLS) is suggested for engine application which is a lightweight aluminum alloy. Mechanical properties like tensile strength, compressive strength, and hardness of both cast and DMLS manufactured alloy are compared followed by analysis of SEM images of tensile test fractured surfaces. Reciprocating wear test is carried out for one lakh cycles at 125°C temperature with SAE 40 grade oil as lubricant. Co-efficient of friction (COF), wear rate of the cast and DMLS manufactured samples are compared. Wear patterns are analyzed using SEM images of the wear tracks.

Various research regarding new types of fabrication and modifications of Aluminium alloy to improve the existing properties are going on. The wide range application of aluminium alloy is in aerospace and Automobile Industries. The demand for this material improved by mechanical properties with little to zero increment in weight. The current work is based on the fabrication of hybrid aluminium metal matrix composites with the addition of TiC (Titanium Carbide) and Al2O3 (Aluminium Oxide) reinforcement particle using stir casting technique. Three types of hybrid composite samples were prepared based on the weight percentage 5% Al2O3+0% TiC (sample-1), 8% Al2O3 + 12% TiC (sample-2), 20% Al2O3+15% TiC (sample-3). The objective of the study is to analyze the mechanical and corrosion properties of the hybrid composite with the influence of the reinforcement and varying the weight fraction of the particles.

Inconel 600 is a face-centered cubic structure and nickel-chromium alloy. Alloy 600 has good resistance to oxidation, corrosion-resistant, excellent mechanical properties, and good creep rupture strength at a higher temperature. Alloy 600 is used in heat treating, phenol condensers, chemical and food processing, soap manufacture, vegetable, and fatty acid vessels. In this context, the present paper investigates the machinability characteristics of Alloy 600 under dry environment. Also, the parametric effect of cutting speed, feed rate, and cutting depth on the force, surface roughness, and tool wear is carried out using 3-Dimensional surface and 1-Dimensional plots. The optimal parameters are determined systematically based on Taguchi-desirability analysis with turned with TiAlN coated carbide insert. From the graphical analysis of collected data, the low rate of feed and moderate cutting for roughness and cutting force and average feed rate for tool wear with low cutting depth.

Inconel 718 has excellent material properties, corrosion, and oxidation property among the nickel based superalloy. This property makes it suitable for producing components operating under extreme environments subjected to pressure and heat. The present study aims to examine the machinability comparison under dry and MQL turning of Inconel 718. The secondary aim is to report the sustainable machining on Inconel 718. Dry and MQL (Minimum Quantity Lubrication) experiments are carried out on Inconel 718 alloy based on Taguchi’s designed L16 orthogonal array. The cutting tools are an advanced coated cutting tool and uncoated tool. The levels of turning parameters are varied at 70, 120, 170 and 220 m/min of turning speed, 0.1, 0.15, 0.2 and 0.25 mm/rev of feed rate and 0.3, 0.4, 0.5 and 0.6 mm of cutting depth. The cutting forces, surface roughness, flank wear, and chip morphology are taken for the current investigation. The factor effect on output responses is studied using 2D plots.

Inconel 825 is nickel (Ni)-iron (Fe)-chromium (Cr) alloy with additions of copper (Cu), molybdenum (Mo), and titanium (Ti). The alloy has excellent resistance to corrosion and is often the most cost-effective alloy in sulphuric acid piping vessels and chemical process equipment. No attempt of applying MQL with three nanofluids was reported conferring to the works accessed. The present study is focused on evaluating the effect of the addition of three nanoparticles (CuO, Al2O3, and CNT) in vegetable oil applied by MQL mode during turning of Inconel 825 with coated carbide tool. Cutting force, surface roughness, and tool wear are evaluated. The results showed that the addition of nCNT substantially improved the machining performance and smaller flank the tool edge, while the adhesion and abrasion are observed as wear mechanism and better results are obtained at 0.5% of nCNT+ vegetable oil to produce the lowest values.

Inconel 625, nickel based alloy, is found in gas turbine blades, seals, rings, shafts, and turbine disks. On the other hand, the manufacturing of this alloy is challenging, mainly when machining processes are used due to excellent mechanical properties. Application of nanofluids in minimum quantity lubrication (MQL) shows gaining importance in the machining process, which is economical and eco-friendly. The principal objective of this investigational work is to study the influence of three types of nanofluids in the MQL turning of Inconel 625 nickel based alloys. The used nanofluids are multi-walled carbon nanotubes (CNT), alumina (Al2O3) and copper oxide (CUO) dispersed in vegetable oil. Taguchi-based L27 orthogonal array is used for the experimental design. The parameter optimization of design variables over response is carried out by the use of Taguchi-based derringer's desirability function.

Nimonic 90A alloy is a nickel-chromium-cobalt alloy and found as a potential material for turbine blades, discs, forgings, a ring section, and hot-working tools. This paper presents the effect of concentration along with cutting speed and feed rate on Fz: cutting force, Ra: surface roughness and Vba: tool wear with the application of two different nanofluids (NFS) on turning of Nimonic 90A by TiAlN PVD carbide cutting inserts. The nanoparticles suspended in oil taken for present investigation are nAl2O3, nCNT, and groundnut oil. The Taguchi L9 orthogonal array and derringer’s desirability response surface has been employed for parameter design and optimal search. 3D surface plots, factor effect plots, Taguchi S/N, and variance tests are used to study the effect of concentration on the machining performance of Nimonic 90A. The statistical analysis revealed % concentration for nCNT and cutting speed for nAl2O3 are found as an influenced parameter on performance characteristics.

The objective of this study is to develop, demonstrate and validate the methodology of external aerodynamic analysis of a State Road Transport bus for prediction of drag coefficient and its impact on fuel consumption with experimental validation. It has been verified that vehicle consumes around 40% of the available engine power to overcome the air drag. This gives us a huge scope to study the effect of aerodynamic drag. Baseline model of State Road Transport Bus was evaluated for estimating fuel consumption using Computational Fluid dynamics (CFD) methodology. The CFD results were validated with the experimental data with less than 10% deviation. Bus design was optimized with an objective of reducing the fuel consumption with parameters like angle of windshield, rounding and tapering corners and rear draft angle. Optimized bus design is also ensured to meet functional specifications as per AIS052.

In recent years, aluminum metal matrix composites (Al-MMC) are found as a potential material for numerous applications owing to its excellent tribological and mechanical properties. In this work, the machining characteristics of aluminum alloy (Al7075) reinforced with TiC/MoS2 having nanoparticle has been studied. The samples of aluminum metal matrix composites by varying TiC in 0, 2 and 4 and MoS2 in 0 and 2 of the percentage weight of aluminum alloy (Composite 1(Al7075), Composite 2 (Al7075/2TiC/2MoS2) and composite 3 (Al7075/4TiC/2MoS2), respectively) are fabricated by the stir-casing method. The turning characteristics of the developed metal matrix composites are studied at various parameters such as cutting velocity (30 m/min, 60 m/min and 90 m/min), cutting depth (0.5 mm, 1.0 mm and 1.5 mm) and composites (1, 2 and 3) using TiN coated cutting tool by dry turning at 0.05 mm/rev feed rate.

The surface properties have a vital role in the overall performance of the parts like brake shoe pad and other frame system. The mechanical and residual stress measurements of aluminium alloy 5083 were investigated on friction stir processed plates using the reinforcements of chromium oxide (Cr2O3) and titanium dioxide (TiO2) separately as well as combination of these powders. A comparative study was made to analyze the effects of reinforcements, tool type (cylindrical and threaded), parameters and the volume fraction of the reinforcements. The mechanical properties such as surface hardness and residual stress of the friction stir processed specimens were investigated. The experimental results shows that there was a significant increase in surface hardness (118 HRC) as well as a decrease in residual stress compare to the base metal. This study also reveals that the threaded tool with a reinforcement of Cr2O3 and TiO2 reflected better mechanical properties than the cylindrical tool.

In the current work the metallurgical and tensile properties of the weld joints of alloy C-2000 were investigated. Welding technique employed in this study is Tungsten Inert Gas Welding (TIG) and Pulsed Current Tungsten Inert Gas (PC-TIG) welding with autogenous mode and Ni-Cr-Mo rich ERNiCrMo-10 filler wire. The results show that PC-TIG weldment obtained the refined microstructure compared to the TIG weldment. Energy dispersive spectroscopy (EDS) showed the extent of Cr segregation was observed in all the weldments. PC-TIG welding shows reduced segregation compared to the corresponding TIG. X-ray diffraction (XRD) corroborated the existence of Ni3Cr2 phases in the weld fusion zone. Tensile test results show the PC-TIG weldment obtained marginally higher tensile properties comparing over the corresponding TIG weldment. The strength of the weldments is inferior in all cases in comparison to base metal.

Nickel based materials of Nimonic C-263 and Waspaloy are used nowadays for aerospace applications owing to its superior strength properties that are maintained at a higher temperature. Tool wear and cutting temperature in the vicinity of cutting edge are two essential machinability characteristics for any cutting tool. In this regard, this study is pursued to examine the influence of factors on measuring of tool wear (Vba) and cutting temperature (Ts) during dry machining of two alloys studied experimentally based on Taguchi method and response surface methodology. Taguchi’s L16 orthogonal array is used to design the experiment and a PVD (TiAlN), CVD (TiN/Al2O3/TiCN) coated carbide inserts are used on turning of two alloys. The factor effect on output responses are studied using analysis of variance, empirical models, and responses surface 3D plots. To minimize the response and to convert into one single optimum level, responses surface desirability function approach is applied.

The main purpose of this study is to investigate additive manufactured Inconel super alloy subjected to cryogenic treatment (CT). Cryogenic treatment is mainly used in aerospace, defense and automobile application. Direct metal laser sintering is an additive manufacturing technique used for manufacturing of complex and complicated functional components. Inconel is an austenitic chromium nickel based super alloy often used in the applications which require high strength & temperature resistant. In this work, a study is carried out on microstructure and mechanical properties of additive manufactured Inconel 718 when subjected to cryogenic treatment at three different time intervals. The micro-structural evolution of IN718 super-alloy before and after CT was investigated by both optic microscope and scanning electron microscope. Surface roughness and hardness at different CT time intervals has also analyzed. Additionally, XRD technique was used to analyze the surface residual stress.