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Body motions of flying animals can be very complex, especially when the body parts are greatly flexible and they interact with the surrounding fluid. The wing kinematics of an animal flight is governed by a large number of variables and thus the measurement of complete flapping flight is not so simple, making it very complex to understand the contribution of each parameter to the performance and hence, to decide the important parameters for constructing the kinematic model of a bat is nearly impossible. In this paper, the influence of each parameter is uncovered and the variables that a specified reconstruction of bat flight should include in order to maximally reconstruct actual dimensional complexity, have been presented in detail. The effects of the different kinematic parameters on the lift coefficient are being resulted.

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 current research work scrutinized the influence of plasma arc in the metallurgical and mechanical behavior of Nimonic 80A weldment. Defect free weld bead of 6 mm thickness was achieved in a single pass through plasma arc welding. The microstructure of weldment is decorated with cellular dendritic structure at the center and at the weld interface region columnar dendritic structure was observed. Metallurgical analysis showed the Cr and Ti secondary precipitates in the interdendritic region of the WZ. The existence of M23C6 and Cr2Ti were observed through the X-ray diffraction analysis. Both tensile test and microhardness test were conducted to study the mechanical properties of weldment. The result concluded that both the strength and ductility inferior than base metal and the hardness of the weld bead is similar to that of BMl.

Turning is a widely used manufacturing process in mechanical machining industries, while the cost associated with this process is high due to the cost involved in changing tools or tool regrinding. All the parameters of turning, like feed rate, cutting speed, and depth of cut, substantially impact the tool wear, which subsequently reduces tool life. Cooling methods like flooding, Minimum Quantity Lubrication (MQL), etc., are incorporated to minimise these effects on the tool and workpiece interface. When using these cooling techniques, the process parameters involved play vital roles in increasing the effectiveness. This paper focuses on the effects of machining parameters on the tool and the workpiece quality. Experiments were conducted to study the impact of various input parameters of the turning process on the tool tip temperature, cutting forces, and tool wear, ultimately affecting the tool's life.

This paper presents the parametric study, process benefits, optimization and chip appearance of machining parameters on turning of the Inconel 718 using Nd: YAG laser source. To analyze the mentioned above effect on alloy 718, the cutting inserts of chemical vapor disposition coated (CVD) TiN/TICN/Al2O3 are used to turn at the time of machining. To evaluate the linear (mean effect plots) and interaction effect (3D surface plots) of laser parameters on the force, roughness and tool wear to keep the minimal, experiments of the L27 orthogonal array are done by selecting the controllable parameters viz speed, the rate of feed along with laser power. From the parametric study, increase in speed and laser power along with decrement in the rate of feed resulted in lower cutting force. But surface finish and tool wear reduced with a decline in speed and scale of feed and increased with increment in laser power.

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 present paper, to predict the process relation between laser-assisted machining parameters and machinability characteristics, statistical models are formulated by employing surface response methodology along with artificial neural network. Machining parameters such as speed of cut; the rate of feed; along with the power of laser are taken as model input variables. For developing confidence limit in collected raw experimental data, the full factorial experimental design was applied to cutting force; surface roughness; along with flank wear. Response surface method (RSM) with the least square method is used to develop the theoretical equation. Furthermore, artificial neural network method has been done to model the laser-assisted machining process. Then, both the models (RSM and ANN) are compared for accuracy regarding root mean square error (RMSE); model predicted error (MPE) along with the coefficient of determination (R2).

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.

Experimental investigations were carried out on the machinable wax filament using the fused deposition modelling (FDM) rapid prototyping process. The printer used for conducting the experiments was Flash Forge guider 2. The filament material used for this study was machinable wax filament of 1.75 mm diameter. Experimental trials were carried out as per Taguchi L9 orthogonal array to determine the optimum process parameter combination. The dimensional analysis of test samples were carried out in terms of change in volume of samples which is result of combine effect of deviations in all the dimensions of test sample. Four factors each at three levels was used to obtain the optimum printing parameters for better dimensional accuracy and proper printing. The four important printing parameters were taken as factor and set to analyse the significant factor affecting on printing. The complexity in printing of wax filament is taken in to consideration during the experimental study.

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.

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.

The present work compares the tribological properties of ZnO (Zinc Oxide) nanoparticle based lubricant with ZDDP (zinc dialkyl dithiophosphate) based lubricant. The nanolubricant was prepared by mixing the nanoparticles in base oil followed by ultrasonification and ZDDP based lubricant was prepared by mixing ZDDP and stirring with base oil. Base oil used was mineral base oil. Both the lubricants were tested at three different temperatures, loads and roughness values. The test was carried out on AISI 52100 steel samples prepared by wire cutting and were grinded to three different levels of surface roughness. Friction and wear tests were performed using a reciprocating sliding tribo-tester at three different loads and temperatures. Taguchi orthogonal array was used to reduce the number of experiments. SEM, EDS and AFM analysis were carried out to study the surface wear phenomenon.

This research work describes the effect of microsegregation, microstructure and tensile strength of the Hastelloy X weldment produced by keyhole plasma arc welding (K-PAW). Weld joint was obtained in a single pass without the addition of filler wire. The significant results obtained in this research work are (i) fine equiaxed dendrite was detected in the weld centre due to lesser heat input (HI) along with the faster solidification attained in K-PAW (ii) The existence of secondary precipitates in the interdendritic boundary was identified by the scanning electron microscope (SEM) analysis (iii) Energy dispersive X-ray spectroscope (EDS) revealed the Cr and Mo microsegregation in interdendritic boundary of the weld zone (iv) X-ray diffraction (XRD) analysis confirmed the Mo-rich P phase and Cr-rich M23C6 phase. The observed tensile strength of weldment is 6.14 % inferior to base metal.