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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.

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 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.

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.

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.

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.

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.

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.

Heat transfer optimization is a crucial aspect of the design process for Formula Student race cars, particularly for the radiator, usually housed in a side pod. For the car to operate at peak performance, a well-designed radiator-sidepod system is essential such that it can dissipate heat generated by the engine faster, for the car to run in optimal performance. Testing the car physically for various radiator-sidepod design iterations is a very difficult task, also considering the costs to manufacture the radiator-sidepod setup. The objective of this study is to develop a comprehensive methodology for analysing heat transfer through radiator setup using Computational Fluid Dynamics and to validate it through experimental investigations, to enhance performance and efficiency of the radiator setup. It further explains how to find out its heat transfer efficiency, and to choose the right radiator-sidepod setup, giving optimal performance.

This paper presents a methodology for predicting thermal comfort inside Midibus cabin with an objective to modify the Heating, Ventilation and Air Conditioning (HVAC) duct design and parametric optimization in order to have improved thermal comfort of occupant. For this purpose the bus cavity is extracted from baseline CAD model including fully seated manikins with various seating positions. Solar Load has been considered in the computational model and passenger heat load is considered as per BSR/ASHRAE 55-1992R standard. CFD simulation predicted the air temperature and velocity distribution inside passenger cabin of the baseline model. The experimental measurements have been carried out as per the guidelines set in APTA-BT-RP-003-07 standard. The results obtained from CFD and Experimental test were analysed as per EVS EN ISO7730 standard and calculated occupant comfort in terms of thermal comfort parameters like Predicted Mean Vote (PMV) and Predicted Percentage Dissatisfied (PPD).

In Additive manufacturing, Direct Metal Laser Sintering (DMLS) is a rapid manufacturing technique used for manufacturing of functional component. Finely powered metal is melted by using high-energy fiber laser, by Island principle strategy that produces mechanically and thermally stable metallic component with reduced stresses, thermal gradients and at high precision. Inconel is an austenitic chromium nickel-based superalloy often used in the applications which require high strength and temperature resistant. It can retain its properties at high temperature. An attempt is made to examine the effect of laser shot peening (LSP) on DMLS Inconel 718 sample. Microstructure shows elliptical shaped structure and formation of new grain boundaries. The surface roughness of the material has been increased due to the effect of laser shock pulse and ablative nature. Macro hardness increased to 13% on the surface.

Surface roughness measurement is an important one in any manufacturing next to dimensions. In this investigation, a vision system and image processing tools were used to develop reliable surface roughness characterization technique for Electrical Discharge Machined surfaces. A CMOS camera with red LED light source were used for capturing images of EDMed surfaces. A separate signal vector generated for all the images from its image pixel intensity matrices. The mean, skewness and kurtosis were obtained from the signal vector. The mean, skewness and kurtosis of the images signal vector correlates very well with the stylus measured hybrid roughness parameters Rda and Rdq. Hence the technique may be preferred for online surface roughness characterization of Electrical Discharge Machined (EDMed) surfaces.