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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.

Vehicle Dynamics testing has its importance in the fields of benchmarking and the validation of mathematical models built in order to predict the ride performance of the vehicle. The importance of enhancing the ride comfort is increasing day by day in present day scenario because of the long hours of driving experience. In presented work, the ride testing is done for two hatchback vehicles on highway conditions in order to compare the ride quality and ride comfort. The parameters like Vibration Dose Value, SEAT factor and Ride Diagram values are used to evaluate the ride comfort. After successful evaluation of the vibration levels affecting the ride comfort of the driver as well as the passenger the next major task is to identify and study the cause of the discomfort. The cause of the discomfort is studied and analyzed in terms of the complex motion of the vehicle. Vehicle motions like choppiness produces higher levels of discomfort as compared to the vertical movement of the vehicle.

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.

Vehicle aerodynamic drag reduction is the effective technique to enhance the fuel economy, performance and top speed of a vehicle. Out of the total drag, the underbody drag contributes about 40-50% by the parts like wheel arch, wheel housing, and the wheels. This further increases in the case of vehicles with higher CG. Thus, it seems logical to focus attention on the underbody aerodynamic drag reduction. In this study, an active spoiler is placed towards the front end of the vehicle which will divert the air flow from the front towards the radiator. The active spoiler revolves according to the signals received from the radar sensors placed at the lower end to detect obstacles which will prevent it from damage. The aim of the study is to examine the effect of the air flow diversion on underbody drag. The effect of air flow diversion on fuel consumption, radiator effectiveness and top speed is numerically evaluated.

Lithium (Li)-based batteries have wide applications in the everyday gadgets. Li-based batteries have prominent usage in the automotive sector. All the major OEMs for manufacturing hybrid electric vehicles (HEVs) and electric vehicles (EVs) use only Li batteries and are still going to continue for the next decades. However, during the operation of these batteries, they are susceptible to environmental and battery factors. The amount of charge currently taken in or out influences the internal resistance and temperature of the battery. Therefore, the amount of heat generated by the Li-ion batteries during operation is critical for designing a cost-effective and efficient thermal management system (TMS) for HEVs and EVs.

Design and simulation analysis of braking system for ATV is carried out with the assistance of Ansys and MATLAB. Heat generated increases the temperature of the disc brake at the rubbing surface resulting in thermal stresses in the components of the braking system. Static, structural, thermal, computational flow dynamics, vibrational & fatigue behavior of ventilated brake disc rotor, hub and upright are analyzed. Stainless Steel, SS-410 material configuration has been considered for disc brake rotor and results obtained are analyzed in terms of performance, longevity and efficiency. Braking efficiency and stopping distance curve are analyzed from their characteristics plot. Vibrational behavior, structural behavior, thermal behavior, performance efficiency, flow behavior of ventilated disc brake rotor can be easily depicted with respect to bump and droop during acceleration, high climb and maneuverability. Ventilated disc brake Rotor with outer diameter of 220 mm is used.

This paper demonstrates the sloshing phenomena of a cylindrical tank with and without baffles. The main objective of this study is to design baffles of different configurations to reduce sloshing in a cylindrical tank partially filled with gasoil-liquid subjected to only longitudinal acceleration and deceleration. Two different baffle designs have been introduced in the present study. A 3-D transient analysis of a cylindrical tank was carried out using ANSYS-FLUENT with and without baffles. Volume of Fluid (VOF) method was used to study the free surface profile of the fluid in the considered tank. Pressure distribution, velocity distribution and force distribution have been studied in the present study. It has been observed that the new design of baffle was able to reduce sloshing effectively.

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.

Friction Stir Welding (FSW) is a widely used solid state welding process in which its heats metal to the below recrystallization temperature due to frictional force. FSW mostly avoids welding defects like hot cracking and porosity which are mainly occur in conventional welding techniques. In this process the combination of frictional force and the mechanical work provide heating the base metal to get defect free weld joints. Aluminium Alloys 2014 and 6061 are generally used in a wide range of automobile applications like Engine valves and tie rod, shipbuilding, and aerospace due to their high corrosion resistance, lightweight, and good mechanical properties. In the present work, aluminium alloys of AA6061 and AA2014 were effectively welded by friction stir welding technique. The tool rotational speed, travel speed, and tool profile are the important parameters in FSW process. High Speed Steel (HSS) tool with Hexagonal profile is used for this joining.

Suspension system of a vehicle plays an important role to carefully control motion of the wheel throughout the travel. The vertical and the lateral dynamics (ride and handling) is affected by the unsprung-to-sprung mass ratio. Lower value of this mass ratio leads to enhanced performance of the car. To optimize the unsprung mass of the car, design of control arm plate is optimized with Aluminum material and Carbon fibre reinforced composite control arms framework are used to achieve high stiffness to weight ratio. These leads to increase in overall power to weight ratio of the car which helps to deliver maximum performance to the wheels. Through analysis of real-life working conditions of the entire steering knuckle assembly in ACP pre- post ANSYS 18.1 with the defined boundary conditions, equivalent stress and total deformations are obtained. Based on the results, geometrical topology of the control arms plates is further optimized.

The drastic technological advancements in the field of autonomous vehicles and connected cars lead to substantial progression in the commercial values of automobile industries. However, these advancements force the Original Equipment Manufacturers (OEMs) to shift from feedback-based reactive business analysis to operational-data based predictive analysis thereby enhancing both the customer satisfaction as well as business opportunities. The operational data is nothing but the parameters obtained from several parts of an automobile during its operation such as, temperature in radiator, viscosity of the engine oil and force applied over the brake disk. These operational data are gathered using several sensors implanted in different parts of an automobile and are continuously transmitted to backend computers to develop Digital Twin, which is a virtual model of the physical automobile.

A Formula Student race car is a car designed and manufactured for speed, performance, and competition. For a car to have high speed and performance, their parts also need to be lighter with being able to sustain the dynamically occurring stresses. Effective braking is a crucial factor which determines the performance of the car. This paper focuses on designing a brake caliper on the basis of calculations done with respect to a Formula Student race car, selecting a material which is of low density but with higher strength which can be easily manufactured with low cost and analyzing the design. Further, the manufactured part is also tested statically to ensure proper working before being tested on an actual formula student race car. The caliper is again tested dynamically, where the caliper is mounted on rear wheels of the car. To ensure proper working, brake pressure sensors are being mounted which also helps to validate the calculations.

This paper describes the design of a novel pneumatic gear shifting system to replace the existing gear stick manual shifting system for ease of the driver while shifting gears. The aim of this work is to have a semi-automatic shifting (pneumatic shifting) removing the need for the driver clutch operation. The system consists of a solenoid valve, CO2 gas-pressurized cylinder, double-acting cylinder, and single-acting cylinder. On basis of the signal received the gear needs to be changed, the shifter opens or closes a magnetic valve assembly. The solenoid valve allows the compressed air into the piston that comes from a pressurized cylinder, in order to create the effect of shifting gears. The pedal shifter and buttons are used to shift the gears. The pedal shifter was designed by using a 3-D printing technique using PLA material. The microcontroller used is ATMEGA-328 in this system. There are three switches, one for upshift, downshift, and clutch respectively.

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.

The final drivetrain ratio is an essential part of a vehicle. It is responsible for providing the desired torque to overcome obstacles while maintaining the speed and acceleration of a vehicle. A vehicle must have an optimum gear ratio to obtain the desired velocity and acceleration. To achieve this, four different approaches were used considering the input parameters of a BAJA All-Terrain Vehicle (ATV). The traction received from the ground is calculated and plotted against velocity on different terrains. Further, a drivetrain was modeled in Simulink to obtain different parameters like vehicle speed, acceleration, and wheel slip. A range of gear ratios was obtained by following a similar trend of vehicle parameters that were best suited for improving vehicle performance. Graphs were plotted to compare the effect of various vehicle parameters, and an optimum gear ratio was obtained.

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).

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.

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.

Composites materials are substituting constituents for traditional materials due to their remarkable properties, and the addition of nanoparticles gives a new development in the material domain. The nanoparticles influence on fabrication and machinability investigation study is essential as the composites to be used in applications like automotive and aerospace. The current study investigates the machinability characteristics of Al2219 based metal composites reinforced with nanoparticles of SiN/MoS2. Al2219- reinforcements (SiN and MoS2) composites are fabricated by the method of stir casting. Four different compositions (Al2219/SiN (2 wt% and 4 wt%), , Al2219/2 wt.% SiN/ 2 wt.% MoS2, Al2219/2 wt.% MoS2) are fabricated by varying the different weight percentages of nanoparticles reinforcements. An attempt is made to study the investigation analysis of force, surface roughness, and tool wear using CNC machine lathe to consider the effect of cutting speed, cutting depth, and samples.