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The present numerical analysis aims at studying the effect of changes in profile of van on aero-acoustic noise and aerodynamic drag. The numerical analysis is carried out using commercial CFD software, ANSYS Fluent, with k-epsilon & Large Eddy Simulation turbulence models. In present study five models of truck are analysed, including baseline model at different Reynolds numbers, namely 0.391, 0.415 and 0.457 million. In order to reduce the aero-acoustic noise, various profile modifications have been adapted on existing van model by adding a top and bottom diffuser at the rear of the truck. The comparison has been done with respect to coefficient of drag, coefficient of pressure, pressure contours for all four cases.

Engine in-cylinder flow structure governs the combustion process and directly influences emission formation and fuel consumption at the source. In naturally aspirated DI diesel engine, combustion process coupled with low pressure mechanical fuel injection systems set different requirements for inlet port performance. In-cylinder swirl needs to be optimized for efficient combustion to meet emission levels and fuel consumption targets. Thus, intake port design optimization process becomes a vital requirement. In the present paper intake port design optimization is carried out for single cylinder naturally aspirated engine using mechanical fuel injection systems. The objective is to investigate in-cylinder flow field developed by intake port designs, study the effects of geometrical details of various port cross sections on flow velocity and pressure fields and establish a relationship with intake port performance parameters i.e. swirl and flow coefficient.

By looking current scenario, engine development lead time was reducing day by day to enter early in the competitive market and to compete as early as possible. During initial engine development phase, it was very important to know how engine operating temperatures were affecting to piston pack and related system. Conventionally temp plug method was used to capture the piston temperature, but it was time consuming, much costly, for every test condition, new temp plug pistons required, if unfortunately, any hot shutdown happened during the test, again full test needs to be restarted with new set of temp plug pistons and many more limitations. So, for Cummins engine we used Telemetry technique to measure the piston temperature ONLINE and in real time. Piston telemetry enables the telemetric transfer of piston data from internal reciprocating and rotating components. The pistons had wireless telemetry to send real time steady state and transient data from within engines.

This paper presents the natural and artificial weathering behavior of different soft skin materials such as leather, leatherette and textiles used for automotive seat cover applications. The objective of this study was to understand the physical and aesthetical changes occurring at these flexible materials under sun UV light and heat exposure. The natural weathering study under glass exposure was carried out as per ASTM G 24 at natural weathering site location and artificial weathering as per SAE J2412 at lab. The material was observed for surface changes such as color, texture, crack and physical changes like flexibility and hardness during the exposure. The sample exposed at natural weathering data for every 15 days were recorded, and artificial weathering for every 100 hours were recorded.

The favorable mechanical properties of Composite materials are excellent stiffness/weight and strength/weight ratios, easy formability and corrosion resistance. The application of composites in structural components is still limited by the difficulty in predicting their service lives. The objective of this research paper is to develop and evaluate damage initiation or delamination onset and growth in a C-C composite 8 layered pre-preg material 3D laminate model (dimension 25x3.4x85mm and ply thickness 1mm) under loading conditions without crack using ANSYS Autodyne tool subjected to a uni-axial load of 40N at the free end. Mapped quadrilaterals mesh is generated with 2610 nodes and 1792 elements. Cohesive Zone Model (CZM) formulations are more powerful than Fracture Mechanics approaches because they allow the prediction of both initiation and crack propagation.

Single point Incremental forming (SPIF) is a metal forming process that has achieved impeccable quality since the early 1990s. ISF is a very limited twisting process in which an improved device that must be used after a particular direction travels on a metal sheet to form the desired shape. Process parameters such as axial feed (mm), feed (mm / min), tool diameter (mm) and depth (mm) at the interface between samples during SPIF greatly affect the quality of the cone. Maximum thinning (mm), cone height (mm), wall angle (mm), formation time (minutes), etc. The purpose of this study was to study these parameters by improving the cone mass formed by VMC. For a detailed study of these parameters, experiments were performed using the orthogonal array L9. Output parameters such as mechanical quality effects were analysed using COPRAS (Complex Proportional Assessment of alternatives) and ANOVA.

Road accidents are increasing now-a-days, Safety of pedestrian is the great concern. In average, 10% of urban pedestrian accidents are fatal. Statistics show that the impact on front side of cars is the major cause of pedestrian deaths (83.5%). The function of a vehicle’s engine hood is to keep its engine covered and allow access to the engine compartment as required for maintenance and repair. The hood structure not only protects the engine cavity, but also keeps pedestrians away from the parts of that cavity. The absorption capability and stiffness of hood structures are the key points considered when designing a vehicle’s hood. The impact of the pedestrian head on automotive hood results in major injuries and sometimes in death. Conventional engine hood results in greater Head Injury Criterion (HIC) values. GFRP pyramidal lattice core structures are used in automobiles which is used for good energy absorption.

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 tracked vehicles, the undercarriage frame components such as track shoes, sprocket, idler, rollers and their configuration plays an important role while transferring the loads from the ground to the main frame. To understand the loads coming on the upper frame and understand the power consumed to drive the vehicle, it is important to model the undercarriage components. This paper presents the methodology for modeling track systems dynamics and its energy analysis. A 3D model of tracked vehicle was developed using commercially available Multi-Body Dynamics tool and validated against test results. The contact parameters between ground and track shoes was determined by varying their values within a defined range based on empirical data available. The undercarriage performance was measured by determining the power required by the hydrostatic drivetrain motor.

The fatigue testing machine mostly used for industrial or laboratory applications are limited to performing single fatigue tests with high leading cost. In the present paper the experimental setup of the traditional fatigue testing machine is integrated with torsional test, to experimentally study the effect of fluctuating stresses on the material under service. In contradiction to earlier machines, the machine herein developed provides uniform bending and twisting moment distribution along the length of the test specimen. The machine performs fatigue test and torsional test, which provides the extreme force needed to understand the properties and behavior of materials. The machine consists of an electric motor to provide the required torque and two circular arms with adjustable chucks to fit test samples of various sizes. The machine provides computerized data for failed samples with data pertaining to each sample.

In the present work, it is aimed at developing an integrated approach for combustor modeling involving rapid prototyping and water tunnel testing to assess the cold flow numerical simulations; the physical model will be subjected to cold flow visualization and parametric studies and CFD analysis to demonstrate its capability for undergoing rigorous cold flow testing. A straight through annular combustors is chosen for the present study because of it has low pressure drop, less weight and used widely in modern day aviation engines. Numerical Analysis has been performed using ANSYS-FLUENT. Three dimensional RANS equations are solved using k-ɛ model for the Reynolds numbers ranging from 0.64 x 105-1.5 x 105 based on the annulus diameter. Post processing the results is done in terms of jet penetration, formation of recirculation zone, effective mixing, flow split and pressure drop for different cases.

Door shut-line definition is the first vital step in car body door engineering and depends on the hinge position, hinge shape, manufacturing capabilities and other parameters. In the design process, once the hinge axis definition is finalized door shut-line is defined which should satisfy two major requirements. The requirements are clearance between the door outer surface with its surrounding components (like hinges, fender, other door etc.) and assembly feasibility. Another one is the manufacturability of the proposed design. The above conditions must be checked on different locations of the door as well as w.r.t different openings of the door. The paper presents a mathematical model to determine the door shut-line position with great computational efficiency. This method propounds closure engineer with parameters to define the shut line rather than going for cumbersome manual iterative process.

Toe setting is one of the major wheel alignment parameters which directly effects handling of a vehicle. Correct toe setting ensures desired dynamic behavior of an automobile like straight line stability, cornering behavior, handling and tire durability. Incorrect setting of toe during design stage significantly deteriorates tire durability and leads to uneven tire wear. In the present scenario of automotive industry, toe setting is majorly an iterative or a trial and error process which is both time consuming and involves higher development cost as there may be instances where 2 to 3 sets of iterations are needed before specification is finalized for production. Therefore, determining optimum toe setting at an early stage of a product development will not only save significant development time but it will also benefit in reducing product validation time and cost.

A Powertrain is one of the major sources of excitation of a vehicle vibration and noise in off highway vehicles. It typically has a significant contribution in whole vehicle NVH characteristics. The structure borne energy of the powertrain is transmitted to the chassis and rest of the vehicle through powertrain mounts. Hence, it is of prime importance to design an effective powertrain mounting system in such a way that it will reduce vehicle vibrations to improve vehicle NVH as well as ride comfort, resulting in an effective vibration isolation system and ensuring long service life. In this paper, a newly developed an analytical tool for effective design of isolation system is discussed. For this model, powertrain is considered as a six degree-of-freedom system. Analytical calculations are implemented to find optimum mount design parameters i.e. stiffness, orientation and position of isolators to meet desired NVH targets.

Activated carbon was produced from a new part of banana plant namely true stem in this current research and used as fillers in polymer composites for automobile application. True stems of banana plants are the main wastes in banana or fruit markets which refer to the remains after banana fruits are removed from the supporting stems. Conversion of raw material into activated carbon particles is done by chemical and heat activation. The raw material used here were dried samples of banana plant’s true stem. This material was heated in a crucible at 400°C and then powdered. These crushed samples were activated using hydrochloric acid at 120°C for 5 hours and finally in a furnace for thermal activation at 700oC for 1 hour. These particles were incorporated as fillers in composites at Proportions of 15%, 25%, 35% and 45%. The activated carbon samples have been characterized by determining its fixed carbon content and bulk density.

In automotive door engineering, fitting the side door glass surface from styling into the cylinder or torus is the basic requirement. Optimization is required to do this, which requires a solver which could be efficacious for best surface fitting. This paper propounds a methodology which could be used for fitting a side door glass surface from styling into the cylinder or torus. The method will significantly help in developing the required surface and can successfully eliminate the cumbersome manual calibrations. The mathematical model mentioned is a novel approach based on “Particle Swarm Optimization” (“PSO” will be used to represent in the paper) towards surface optimization technique. VB script is used to make it applicable in CATIA but could be easily applied in any other programming language like python, java etc. Usually the surface fitting problems deals with the initial guess of the required surface and then its further optimization.

The selection of material in automotive design is one of the most important factors. There are variety of materials that can be used in automotive Body and Chassis system design. However challenge is to select a right kind of material to meet functional requirement of a component or system. Some of the criterions that a material should meet are lightweight, economic effectiveness, safety, recyclability and life cycle requirements. Some of these criterions are result of regulatory, vehicle performance or customer needs. However, some of these requirements would be conflicting to each other, therefore optimization is need of the hour. In today’s scenario automotive engineers are being challenged to use lightweight materials considering all design and commercial conditions. As industry is moving towards electrification of vehicles, we need to have light weight vehicles in order to meet range requirement.

In automotive industry, many of the powertrain components (for e.g. engine head and cylinder block) are generally manufactured by a casting procedure. Secondary Dendrite Arm Spacing (SDAS) is one of the most important microstructural features in dendritic solidification of alloys (for e.g. Al-Si alloys) during the casting process. SDAS has a significant influence on the mechanical behavior of the cast aluminum components. A lower value of SDAS is desired in order to achieve better fatigue strength of the cast components which can be controlled by governing several casting parameters. For directional solidification, SDAS is dependent on various casting parameters i.e. chemical composition of the alloy, cooling rate and liquid melt treatment. During industrial casting of an alloy with predefined chemical composition, cooling rate during the mushy zone becomes the dominant parameter for controlling SDAS.

Active control mainly comprises of three parts; sensor-detects the input disturbance, actuator -provide counter measures and control logic -processing of input disturbances and converting it into logical output. Lot of methods for active vibration control are available but this paper deals with active control of steering wheel vibrations of an LCV. A steering wheel is, one such component that directly transfers vibration to the driver. Active technique described here is implemented using accelerometer sensor, IMA (Inertial Mass Actuator) and feed forward Fx-LMS (Filtered reference Least Mean Square) control algorithm. IMA is a single-degree-of-freedom oscillator. To enable a control, IMA needs to be coupled to the structure at a single point, acting as an add-on to the passive system. Fx-LMS is a type of adaptive algorithm which is computationally simple and it also includes compensation for secondary path effects by using an estimate of the secondary path.

Cabin noise is a significant product quality criteria which enables the customers for product differentiation. There are various sources of cabin noise such as wind, structures(panels), engine, suspension, tire and roads. During product development phase, extensive tests has been conducted to improve vehicle dynamics behavior on various climatic conditions. One such test is accelerating vehicle on low mu or icy surface. While performing acceleration manoeuvre (tractions) on a low mu tracks, Cabin noise with source identified from front underbody & low tractive torque build up is reported. This undesirable behavior may occur due to following reason (1) Excitation of coupled modes between suspension and powertrain which induces torque fluctuation. (2) Transmissibility of various subsystem can be the reason for above problem statement. (3) Poorly chosen tire compounds and design leads to fluctuation in torque.